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AJSLP
Clinical Focus
Elements of Phonological Interventions for
Children With Speech Sound Disorders:
The Development of a Taxonomy
Elise Baker,
a
A. Lynn Williams,
b
Sharynne McLeod,
c
and Rebecca McCauley
d
Purpose: Our aim was to develop a taxonomy of elements
comprising phonological interventions for children with speech
sound disorders.
Method: We conducted a content analysis of 15 empirically
supported phonological interventions to identify and describe
intervention elements. Measures of element concentration,
flexibility, and distinctiveness were used to compare and
contrast interventions.
Results: Seventy-two intervention elements were identified
using a content analysis of intervention descriptions then
arranged to form the Phonological Intervention Taxonomy: a
hierarchical framework comprising 4 domains, 15 categories,
and 9 subcategories. Across interventions, mean element
concentration (number of required or optional elements) was
45, with a range of 27 to 59 elements. Mean flexibility of
interventions (percentage of elements considered optional
out of all elements included in the intervention) was 44%,
with a range of 29% to 62%. Distinctiveness of interventions
(percentage of an intervention’s rare elements and omitted
common elements out of all elements included in the
intervention [both optional and required]) ranged from 0%
to 30%.
Conclusions: An understanding of the elements that
comprise interventions and a taxonomy that describes their
structural relationships can provide insight into similarities
and differences between interventions, help in the identification
of elements that drive treatment effects, and facilitate faithful
implementation or intervention modification. Research is
needed to distil active elements and identify strategies that
best facilitate replication and implementation.
Numerous interventions for children with speech
sound disorders (SSD) have been developed over
the past 100 years (e.g., Swift, 1918) to offer cli-
nicians effective approaches for addressing the needs of
children ranging from those who demonstrate a few resid-
ual speech errors to those with severe unintelligibility. These
interventions have been disseminated through tutorial and
empirical articles, workshops and book chapters, and even
entire books dedicated to specific interventions (for a sum-
mary, see E. Baker & McLeod, 2011; McLeod & Baker,
2017; Williams, McLeod, & McCauley, 2010). Developers’
accounts of these approaches reflect their ideas about the
elements that comprise and contribute to the efficacy of
their approach, such as goals, teaching procedures, and
evaluation strategies. In this context, elements are funda-
mental building blocks of an intervention that characterize
an approach. Clear and explicit description of these elements
enables faithful replication and implementation. Clear de-
scription also helps clinicians make informed choices given
the diversity of approaches on offer.
The purpose of this article is twofold—first, to report
on the development of the Phonological Intervention Taxon-
omy to identify the elements of well-studied pediatric pho-
nological interventions and, second, to illustrate how the
taxonomy could help increase the transparency of inter-
vention descriptions, thereby supporting clinical training and
research into the contribution and necessity of intervention
elements. We selected phonological interventions rather than
articulatory or motor speech interventions because they
represent the largest group of interventions currently avail-
able for children with the most common type of SSD—
phonological impairment (E. Baker & McLeod, 2011). In
this introduction, we explain the importance of clarity in
intervention descriptions, consider how clarity can be addressed
a
Discipline of Speech Pathology, Faculty of Health Sciences,
The University of Sydney, New South Wales, Australia
b
East Tennessee State University, Johnson City
c
Charles Sturt University, Bathurst, New South Wales, Australia
d
The Ohio State University, Columbus
Correspondence to Elise Baker: elise.baker@sydney.edu.au
Editor-in-Chief: Krista Wilkinson
Editor: Kristie Spencer
Received August 17, 2017
Revision received January 2, 2018
Accepted January 29, 2018
https://doi.org/10.1044/2018_AJSLP-17-0127
Disclosure: A. Lynn Williams, Sharynne McLeod, and Rebecca McCauley are
co-editors of the book Interventions for Speech Sound Disorders in Children,
published by Paul H. Brookes Publishing, as referred to in the manuscript, and
receive royalty payments on the sale of the book. Elise Baker has declared that
no competing interests existed at the time of publication.
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through a priori (top-down) and a posteriori (bottom-up)
strategies, and reflect on the state of phonological interventions
for children with SSD with respect to replication and
diversity. In doing so, we establish the need and a methodol-
ogy for the development of the Phonological Intervention
Taxonomy.
The Importance of Clarity
in Intervention Descriptions
All stages of intervention development (Fey &
Finestack, 2009) and clinical application (Kaderavek
& Justice, 2010) require clear descriptions of the many
aspects of an intervention, from the methods used to iden-
tify, assess, and describe individuals receiving the interven-
tion (Hammer, 2011; McCauley & Demetras, 1990) through
to the elements that comprise the intervention itself. Clarity
in these descriptions is important for four key reasons.
First, clarity promotes replicability, a bedrock concept
of modern scientific methods (Plutchik, 1983). The para-
mount importance of replication is underscored by method-
ologists who argue that claims made on the basis of
single studies should be interpreted cautiously (M. Baker,
2015; Ioannidis, 2005), especially when samples are small
and likely to be biased by the reporting of only positive
or selected outcomes. Recently, commitment to the impor-
tance of replications has intensified across many disciplines
because large-scale replication efforts are demonstrating
that single studies, even those of very high quality, may
not be replicable. In a groundbreaking replication of 100
research findings in psychology, only 39 key findings were
fully reproduced in direct replications of study designs
(M. Baker, 2015; Open Science Collaboration, 2015). Simi-
larly, in medicine, Ioannidis (2005) examined the results
of relatively loose replications (i.e., studies in which the
same research questions were addressed) and found that
the process resulted in modifications to previous evaluations
of the direction, strength, and meaning of observed effects.
More recently, Ludemann, Power, and Hoffmann (2017)
examined the replicability of randomized controlled trials
across 162 speech-language pathology interventions. Using
the Template for Intervention Description and Replication
checklist (Hoffmann et al., 2014), Ludemann et al. (2017)
reported that none of the articles rated had sufficient detail
to enable replication. Although searches for additional
information (e.g., protocol papers, websites, contact with
authors) yielded more detail, the overall finding was that
intervention elements were inadequately described. Regretta-
bly, although the need for replication is often taken as
axiomatic, it would seem that replications are largely absent
or often may not be possible (given insufficient intervention
descriptions) in educational and behavioral research (Makel
& Plucker, 2014; Malouf & Taymans, 2016) and speech-
language pathology (Ludemann et al., 2017; Muma, 1993).
In the area of speech sound interventions, E. Baker
and McLeod (2011) conducted a narrative review of
134 peer-reviewed studies of phonological interventions for
children with SSD and identified 46 different phonological
intervention approaches. Only half of these (n= 23) had
been studied and reported in more than one publication,
and exact replications were limited both in number and
diversity of authors. For example, although minimal pairs
therapy was investigated in 42 studies by 21 different groups
of researchers (E. Baker & McLeod, 2011), lack of consen-
sus on the ideal combination of elements comprising the
approach and insufficient methodological detail (i.e., lack
of clarity) meant that few of the studies of this approach
could be considered direct replications (E. Baker, 2010).
Without increases in the clarity of methodological descrip-
tion (including the elements that comprise the interven-
tions), replication research on this topic will remain sparse
and, even when undertaken, will likely be flawed.
A second reason that clarity or transparency in inter-
vention descriptions is of prime importance is its role in
establishing intervention integrity (also known as fidelity
or procedural reliability). Intervention integrity refers to
“the extent to which essential intervention components [i.e.,
elements] are delivered in a comprehensive and consistent
manner by an interventionist trained to deliver the inter-
vention”(Sanetti & Kratochwill, 2009, p. 448). Credible,
data-driven statements about the integrity of an inter-
vention help to bolster claims about relationships between
the independent and dependent variables (internal validity)
and generalizability (external validity). Studies using an
intervention with high integrity allow research consumers
to be confident that reported outcomes are based on the
intervention rather than on uncontrolled variables. Of course,
the very idea that an intervention can be implemented
in the intended manner is predicated on an assumption
that the elements of an intervention have been made
explicit.
Third, clear description of interventions allows
researchers to study the effect of particular elements, with
multiple benefits. It allows researchers to identify and sepa-
rate essential from supplementary elements, with essential
elements being those critical for success (Abry, Hulleman,
& Rimm-Kaufman, 2015; Sanetti & Kratochwill, 2009).
It can help researchers identify and modify elements so
that they are more effective or adapt elements so that
they are more amenable to real-world adoption, imple-
mentation, and maintenance and are less susceptible to
breakdowns along the multistep path to widespread use
(e.g., Dingfelder & Mandell, 2011; Embry & Biglan, 2008).
Research examining the effect of specific elements also
allows researchers to explore the cost effectiveness of dif-
ferent groups of elements and to distil or refine approaches
by identifying and removing elements of no consequence.
Oftenreferredtoascomponent analysis, such research
often has been conducted using single subject experimen-
tal designs (Ward-Horner & Sturmey, 2010), but group
designs have also been used for this purpose (Abry et al.,
2015).
Finally, clear and detailed descriptions are central
to speech-language pathologist (SLP) training and ongo-
ing continuing education (Dijkers, 2015; Michie et al.,
2011). They help clinicians understand what is required
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for implementation and determine what knowledge, skills,
and/or resources they already have and /or what they
need to acquire to faithfully implement an approach. Clear
and detailed descriptions may also help clinicians engage
in more informed and systematic modification of inter-
ventions to address client needs and preferences than cur-
rent “eclectic”modifications reported to be used by SLPs
(Brumbaugh & Smit, 2013).
A Priori Versus A Posteriori Knowledge
What do we know about phonological interventions
and the elements they comprise? A helpful way of think-
ing about this question is to think about the origins of
knowledge. Based on the work of the German philosopher
Immanuel Kant (1724–1804), there are two paths from
which knowledge can emerge—knowledge can be a priori
and a posteriori (Müller-Merbach, 2007). A priori knowl-
edge emerges from the mind, through deductive reasoning.
It can arise from predetermined theories or a set of ideas
without experimental foundation. By contrast, a posteriori
knowledge comes from our sensory experience of the world
(Müller-Merbach, 2007). It emerges from experimentation
and observation. To appreciate the difference between
these two sources of knowledge, consider the following sce-
nario. If a novice clinician was asked to think about what
teaching procedures might help a child produce a contrast
between plosives and fricatives in words, the novice clini-
cian could generate ideas, that is, a priori knowledge. If the
same novice clinician was asked to observe an experi-
enced clinician conduct a minimal pairs intervention ses-
sion targeting stopping of fricatives, the novice clinician
could describe what was said and done—that is, generate
a posteriori knowledge from observation. Both types of
knowledge are important for informing our understanding
of intervention elements.
The A Priori (Top-Down) Description
of Intervention Elements
Over the past decade, the issue of clarity in research
descriptions has been addressed through predetermined
guidelines and checklists provided by organizations tasked
with the improvement of research quality. The highly
influential Consolidated Standards of Reporting Trials
(CONSORT) statement was prepared to offer guidelines
for the reporting of randomized controlled trials (Moher,
Schulz, Altman, & the CONSORT Group, 2001; Schultz,
Altman, Moher, & the CONSORT Group, 2010), with
medical researchers as the primary audience. In 2004, a
related document, the Transparent Reporting of Evalua-
tions of Non-Randomised Designs (TREND) statement
(Des Jarlais, Lyle, Crepaz, & the TREND Group, 2004)
offered similar guidelines but for nonrandomized studies,
such as those frequently used in studies of behavioral and
public health, rather than medical interventions.
The Journal Article Reporting Standards (JARS), which
appear in the sixth edition of the Publication Manual of the
American Psychological Association (American Psychologi-
cal Association, 2010), are built upon the CONSORT
and TREND statements. For journal articles in which an
experimental manipulation or intervention is studied, the
JARS stipulate eight relevant topics related to intervention
description: intervention content, method of intervention
delivery, deliverer, setting, exposure quantity and duration,
time span, and activities to increase compliance or adher-
ence (e.g., incentives). In addition, authors need to specify
the language used (other than English) and translation
method. For example, the topic “time span”is described
as “how long it took to deliver the intervention or manipula-
tion to each unit”(American Psychological Association,
2010, p. 249). These various sets of standards or predeter-
mined ideas about the type of information that should be
included in intervention descriptions are among many that
are being developed by professional and scholarly communi-
ties to improve our knowledge about interventions of all
kinds.
Additional methods for ensuring clarity in inter-
vention descriptions include manualization and the system-
atic documentation of intervention integrity (e.g., Eifert,
Schulte, Zvolensky, Lejuez, & Lau, 1997; Kaderavek &
Justice, 2010). Manualization involves the transformation
of an intervention idea or prototype into a robust replica-
ble solution that enables reliable implementation by others.
Manualization requires explication of elements compris-
ing a specific intervention approach, such as the goals
(i.e., what is targeted), procedures (i.e., how goals are ad-
dressed), expected responses from children (i.e., children
listen to and/or produce speech), and intervention in-
tensity (i.e., session dose, frequency, duration, and total
intervention duration; E. Baker, 2012; Warren, Fey, &
Yoder, 2007). Manualized interventions typically com-
prise written guidelines or a manual and, if need be, train-
ing and resources. Once prepared, intervention manuals
can be used during efficacy and effectiveness studies and,
later, during implementation (e.g., McCartney et al.,
2004). Manualization also permits the systematic docu-
mentation or recording of how well a clinician implements
an intervention.
Although not used to guide intervention research in
the same way as an intervention manual, variations on a
structural model of intervention developed by Fey et al.
(Fey & Finestack, 2009; McCauley & Fey, 2006; McCauley,
Fey, & Gillam, 2017) have been associated with several
books describing interventions in communication disorders
(e.g., Guitar & McCauley, 2010; Prelock & McCauley, 2012;
Williams et al., 2010). Many of these interventions are
also represented in part by accompanying video content—
combining aprioriwith a posteriori knowledge. Unlike man-
ualized interventions that make clear how to implement
specific intervention approaches, structural models provide
a framework of the generic elements that might comprise
interventions. In McCauley and Fey (2006), the model
components or elements consisted of intervention agents,
intervention contexts, intensity, procedures, activities, mea-
surement of outcomes, goal attack strategies, and three
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components related to goals that were differentiated by
their level of abstraction (i.e., basic, intermediate, and spe-
cific). In a subsequent revision of the model (McCauley
et al., 2017), service delivery models were added as an addi-
tional element.
In addition to intervention manuals and structural
models, promotion of intervention integrity or fidelity can
involve methods, such as the use of a procedural checklist
(e.g., Dijkers, 2015; McIntyre, Gresham, DiGennaro, &
Reed, 2007) and behavioral observation of clinicians using
an intervention, to ascertain that predetermined elements
are being used and implemented in accordance with devel-
opers’aprioriintentions (Kaderavek & Justice, 2010).
Procedural checklists itemize the methods described in an
intervention manual as a means of promoting integrity
of implementation or fidelity. In contrast to comprehensive
manuals, procedural checklists outline important or key
elements of an intervention. However, all of these strategies—
manuals, structural models of intervention, and checklists—
almost always fail on central questions related to how
elements of an intervention contribute to outcomes (Dijkers,
2015).
Consequently, another approach to the improved
descriptions of interventions has arisen that is more disci-
pline- and practice context-specific and, explicitly, more
theoretically driven. This approach involves the develop-
ment of intervention classification systems or taxonomies
built with primary attention to theory, in particular to
theories about how interventions work. For example,
in 2016, Turkstra, Norman, Whyte, Dijkers, and Hart in-
troduced the speech-language pathology audience to the
rehabilitation treatment taxonomy (RTT), a classification
system being developed in the rehabilitation literature (e.g.,
Dijkers, Hart, Whyte, Zanca, Packel, & Tsaousides, 2014;
Whyte, Dijkers, Hart, Zanca, Packel, Ferraro, & Tsaousides,
2014).
Treatment theory—a theory about how and why an
intervention works—is seen as central to the development
of the RTT (Turkstra et al., 2016). In the RTT, interven-
tion consists of measurable ingredients (i.e., clinician’s
actions that can range from the use of a device to environ-
mental modifications to modeling and prompting) that
act upon measurable treatment targets through a mecha-
nism of action (known or hypothesized). Of particular
interest is the distinction between active versus inactive
ingredients, with inactive ingredients being those that
are included in an intervention but may not contribute to
effects on a particular target. In the RTT, for each target,
the relevant ingredient associated with the means of action
comprises a treatment component. Aims are described
as the ultimate functional outcomes resulting from the
achievement of one or more targets, for example, they
give the example of improved conversation as an aim
that may require different treatment components. This
distinction is similar to that associated with the several
levels of goals (basic, intermediate, specific) in existing
models in speech-language pathology (e.g., McCauley
et al., 2017).
The A Posteriori (Bottom-Up) Search
for Intervention Elements
In contrast to a priori descriptions of intervention
elements, researchers across many applied social and behav-
ioral sciences, such as clinical psychology, nursing, health
promotion, and education, have identified and described ele-
ments a posteriori (e.g., Abraham & Michie, 2008; Dunst,
Raab, & Trivette, 2011; Embry & Biglan, 2008; Michie,
Fixsen, Grimshaw, & Eccles, 2009). That is, they identified
elements through observation and/or reading empirically
based information without the guidance of aprioriproce-
dural checklists. In this way, the problem of circularity or
describing an intervention by the elements detected from a
list to the detriment of failing to detect elements not on a
list can be mitigated.
To date, few such efforts have been undertaken in
communication disorders. For example, Andrews, Guitar,
and Howie (1980) conducted a meta-analysis of 42 studies
of techniques used to improve stuttering and attitudes in
persons who stutter. They found that prolonged speech and
gentle onset techniques produced better long-term (6 months
post therapy) and short-term outcomes than techniques
that focused on attitude or airflow. In another example,
Dunst et al. (2011) used content analysis to identify the ele-
ments (referred to as characteristics) of six naturalistic lan-
guage intervention approaches. Dunst et al. identified three
broad characteristics (child, adult setting, and adult char-
acteristics) across the approaches and 11 features within
these broad characteristics (e.g., caregiver responsiveness,
joint interactions, child engagement). They further unpacked
the approaches identifying 32 elements, coding the explicit
presence (+), implied presence (−), or absence (0) of each
element for each approach. In doing so, they identified
the potential key elements of naturalistic language in-
terventions. These two examples illustrate the value of
using an a posteriori strategy to identify the elements of
interventions.
Most recently, Van Stan, Roy, Awan, Stemple, and
Hillman (2015) created a taxonomy of voice therapy using
a priori and a posteriori strategies. Van Stan et al. set out
to develop a taxonomy that was concise, accurate, made
use of a dictionary/thesaurus as a way of standardizing ter-
minology, and drew on previous categorical descriptions of
therapy (e.g., direct vs. indirect interventions). Further, the
authors intended to define a taxonomy that could be used
to describe “what happens during a voice therapy session”
(p. 103), indicating that the taxonomy would allow for a
temporally changing description of the variety of elements
occurring within or across multiple sessions. As a means
of demonstrating the utility of their taxonomy, Van Stan
et al. used portions of it (specifically, their subcategoriza-
tion of direct interventions by vocal subsystem) to charac-
terize and compare seven well-known therapy programs on
the basis of descriptions of them in peer-reviewed articles
and relevant review articles. In their discussion, Van Stan
et al. noted the potential educational and clinical value
of structured descriptions on the basis of their taxonomy.
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Perhaps, because the decision methods used in this un-
dertaking were reportedly based on consensus, the reliabil-
ity of descriptions on the basis of the taxonomy was not
evaluated. Nonetheless, this article represents an impor-
tant step forward in the rigorous development of taxon-
omies for speech-language pathology interventions using
both data and theory.
In summary, whereas aprioridescriptions of interven-
tion structure have largely been recommended or undertaken
to aid in the clarity of descriptions of specific interventions,
a posteriori efforts to identify elements can lead to power-
ful advances in the systematic comparison of interventions
intended for specific populations or to address specific
skills. By identifying shared and distinct elements, such
efforts may offer consumers a clearer idea of the real alter-
natives presented by superficially similar interventions,
researchers a clearer idea of which elements deserve greater
scrutiny, and educators a clearer idea of how best to
facilitate learners’faithful implementation of intervention
elements.
Thus, in order to advance an examination of inter-
vention structures in phonological interventions, we report
on a qualitative study, then on the use of its findings to
describe interventions. Specifically, we describe the devel-
opment of a Phonological Intervention Taxonomy on the
basis of an a posteriori description of the elements from a
group of empirically supported phonological intervention
approaches for children with SSD. Textual descriptions of
the interventions were used as input to that process. Sec-
ond, we use the taxonomy to offer a broad overview of the
15 studied approaches in terms of the number of elements
used (i.e., concentration), the proportion of elements indi-
cated as optional within each approach out of all included
elements (i.e., flexibility), and the extent to which an inter-
vention included rare or uncommon elements and omit-
tedcommonelementsoutofall included elements (i.e.,
distinctiveness).
Method
Data Inclusion Criteria
Fifteen phonological intervention approaches were
selected to develop a Phonological Intervention Taxonomy
(see Table 1 and reference list*).
1
They were selected be-
cause they were supported by peer-reviewed experimental
evidence, and they each had been described in a chapter
published by Williams et al. (2010). Each chapter had been
written by, in most cases, an author who had played an
important, even principal role in the development of the
approach. Each chapter had been written according to
a prescribed template that defined specific information to
be included in sections marked by specified headings and
subheadings along with associated page limits (see Appen-
dix A). Although the relatively rigid format of the chap-
ter template had originally been intended to provide an
aprioridescription of key intervention elements, the methods
used in the content analysis reported on here was intended
to avoid the simple reproduction of the template elements
as elements.
Researchers
In keeping with requirements of rigor in qualitative
research methodology (Lincoln & Guba, 1985), the re-
searchers’potential sources of bias warrant acknowledge-
ment. Each of the four researchers has worked with and
conducted research into children with SSD for over a de-
cade or more and has also spent considerable time writing,
reading, and reviewing research on interventions for this
population, including as authors and editors of Williams
et al. (2010). Methods used to limit the impact of researcher
preconceptions will be described in the procedural descrip-
tions that follow.
Procedure
The research was undertaken in two phases. Phase 1
involved a qualitative thematic analysis using an inter-
pretivist approach (Hatch, 2002; Yin, 2011) to isolate mean-
ing statements reflecting possible intervention elements. This
phase was undertaken in order to identify and construct the
Phonological Intervention Taxonomy. Phase 2 was an analy-
sis of each intervention chapter’s text to determine whether
the elements in the taxonomy were required, optional, or
absent (not present and/or not explicitly mentioned) for
each of the 15 approaches.
Phase 1: Content Analysis to Identify Elements
The content analysis entailed nine steps to identify
intervention elements. These steps involved identification
of meaning statements within text describing each inter-
vention, combining related statements, and organizing them
into a hierarchy of thematic domains, categories and sub-
categories, and elements (Yin, 2011). (1) Chapter text con-
tained under the headings “Practical Requirements”and
“Key Components”for each of the 15 studied phonologi-
cal intervention approaches from Williams et al. (2010; see
Appendix A) was combined into a single electronic docu-
ment. (2) The first three researchers collaboratively read
one intervention approach and highlighted meaning state-
ments. A meaning statement was defined as a unit of infor-
mation conveying one idea. A meaning statement could
comprise one word within a sentence, a short phrase, a sen-
tence, or series of sentences, as long as the written information
1
Intervention approaches included in the review are identified in this
clinical focus article by capitalization of the first letter of each word
(e.g., Multiple Oppositions [Williams, 2010]), or where relevant the
customary acronym (e.g., Parents and Children Together = PACT
[Bowen, 2010]; Enhanced Milieu Teaching with Phonological
Emphasis = EMT/PE [Scherer & Kaiser, 2010]). Camarata (2010)
describes two approaches to naturalistic speech intervention:
Naturalistic Intervention for Speech Intelligibility (NISI) and
Naturalistic Intervention for Speech Accuracy. Only NISI was
included in the review.
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contained only one idea. Most sentences contained at least
one, and sometimes several, meaning statements. For
example, this sentence from the Stimulability approach
(Miccio & Williams, 2010, p. 189) was chunked into five
separate meaning statements (emphasis added): “Use the
[associated hand/body motions]to[bring their children’s
attention to the target sounds][at home]to[encourage speech
production] within a [nonthreatening atmosphere].”This
process of defining and identifying meaning statements
was discussed and agreed upon by the first three researchers
through the collaborative training process—reading and
identifying individual meaning statements from the same
chapter text, together. (3) The same three researchers then
were randomly allocated with five intervention approaches
each and independently chunked the text into meaning
statements, retaining information about the source of the
statement. (4) Next, they independently categorized the
individual meaning statements into what they saw as over-
arching themes of intervention. (5) At the next step, all
four researchers met, including the three researchers involved
in Steps 1–4, and shared the overarching themes they had
identified. There were many consistencies between the iden-
tified themes of the three researchers, despite each con-
sidering different intervention approaches. (6) The group
discussed the themes that had been identified and agreed
on consolidating some themes while leaving others as origi-
nally identified by one of the coding researchers. In this
way, an initial taxonomy was developed. (7) For each theme,
the associated meaning statements were reviewed by the
group to determine whether the appropriate categorization
was made across all of the intervention approaches. For
example, there were 120 meaning statements initially labeled
Table 1. Characterization of the 15 interventions included in the current review in terms of concentration, flexibility, and distinctiveness.
Intervention approaches
a
No. of
elements coded
as required
(and optional)
b
No. of rare
elements included
(and common
elements omitted)
c
Concentration
d
Flexibility
e
Distinctiveness
f
Complexity (Complexity Approaches to
Intervention; E. Baker & Williams, 2010)
24 (14) 3 (0) 38 37% 3/38 (8%)
Core Vocabulary (Core Vocabulary
Intervention; Dodd et al., 2010)
27 (15) 1 (0) 42 36% 1/42 (2%)
Cycles (The Cycles Phonological
Remediation Approach; Prezas &
Hodson, 2010)
32 (15) 1 (0) 47 32% 1/47 (2%)
Dynamic Systems (Dynamic Systems
and Whole Language Intervention;
Hoffman & Norris, 2010)
30 (12) 2 (0) 42 29% 2/42 (5%)
EMT/PE (Enhanced Milieu Teaching
with Phonological Emphasis for
Children with Cleft Lip and Palate;
Scherer & Kaiser, 2010)
27 (19) 2 (2) 46 41% 4/46 (9%)
Metaphonology (Metaphonological
Intervention; Phonological Awareness
Therapy; Hesketh, 2010)
27 (24) 1 (0) 51 47% 1/51 (2%)
Minimal Pairs (Minimal Pair Intervention;
E. Baker, 2010)
22 (26) 2 (0) 48 54% 2/48 (4%)
Morphosyntax (Morphosyntax Intervention;
Tyler & Haskill, 2010)
24 (18) 3 (2) 42 43% 5/42 (12%)
Multiple Oppositions (Multiple Oppositions
Intervention; Williams, 2010)
26 (25) 1 (0) 51 49% 1/51 (2%)
Nonlinear (Nonlinear Phonological Intervention;
Bernhardt et al., 2010)
18 (29) 0 (0) 47 62% 0/47 (0%)
NISI (Naturalistic Intervention for Speech
Intelligibility; Camarata, 2010)
17 (13) 0 (7) 30 43% 7/30 (23%)
PACT (Parents and Children Together Intervention;
Bowen, 2010)
36 (23) 1 (0) 59 39% 1/59 (2%)
Psycholinguistics (Psycholinguistic Intervention;
Stackhouse & Pascoe, 2010)
25 (34) 3 (0) 59 58% 3/59 (5%)
Speech Perception (Speech Perception
Intervention; Rvachew & Brosseau-Lapré, 2010)
13 (14) 2 (6) 27 52% 8/27 (30%)
Stimulability (Stimulability Intervention; Miccio
& Williams, 2010)
29 (18) 3 (0) 47 38% 3/47 (6%)
Average 25 (20) 1.7 (1.1) 45 44% 2.8 (6%)
a
Short name of intervention in bold (used to refer to intervention throughout current article), followed by chapter title and author(s) in Williams
et al. (2010).
b
Elements coded as optional are shown in parentheses ( ) next to elements coded as required.
c
Omitted common elements are
shown in parentheses ( ) next to rare elements.
d
Total number of elements.
e
Percentage of elements coded as required over total elements.
f
Total rare + omitted common elements/total elements per approach, with percentage shown in parentheses ( ).
6American Journal of Speech-Language Pathology •1–30
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by the researchers as Parent education (n= 47), Family
(n= 49), Homework (n=20),Homepractice(n=3),and
Home practice: technology (n= 1). After reconsidering these
meaning statements within the broader intervention taxon-
omy, they were reclassified and hierarchically arranged
into categories and subcategories. For example, a parent
was considered to be a type of intervention agent, which
was considered to be part of the overall intervention con-
text. (8) The four researchers then tested the Phonological
Intervention Taxonomy by locating exemplar quotes
for each of the identified categories and elements. (9) To
conclude Phase 1, the first researcher then read and iden-
tified intervention elements in a second source of liter-
ature for each intervention approach, a peer-reviewed
published article (i.e., 15 articles), to determine if satura-
tion of elements across the 15 phonological interventions
had been reached. No new elements were identified in this
step, as all identified elements could be classified using the
taxonomy.
The final version of the Phonological Intervention
Taxonomy is outlined in Figure 1. This taxonomy involves
a branching framework that includes up to four levels.
At the broadest level is domain, which provides the over-
arching organization or construction of the taxonomy and
defines a major property of interventions in general. As
shown in Figure 1, there are four intervention domains:
goal, teaching moment, context, and procedural issues.
The second level of the taxonomy, category, is a smaller
self-contained constituent of a domain. For example, under
the domain teaching moment, categories are antecedent
event, response, and consequent event. The third level,
subcategory, provides greater differentiation and is evident
in two of the four broad domains (teaching moment and
context). The final level, element, is the smallest build-
ing block of an intervention in this taxonomy. We chose
the term element rather than ingredient to avoid the poten-
tial for confusion with the definition of ingredient by
Turkstra et al. (2016, p. 165), namely, “specific actions taken
by the clinician to effect changes in the target.”As such,
elements encompass ingredients in addition to information
about goals, intervention context, and other procedural
aspects. Across the 15 categories and nine subcategories of
the Phonological Intervention Taxonomy, 72 intervention
elements were identified. Definitions and examples for all
elements are provided in Appendix B.
Phase 2: Coding Analysis to Identify Elements
Once the Phonological Intervention Taxonomy was
created, a 3-point scale was applied based on Dunst et al.
(2011) to differentiate whether or not an element was part of
the intervention approach. The 3-point scale allowed for an
element to be coded as (a) required (score = 2), (b) optional
(score = 1), or (c) absent (score = 0) in descriptions of each
approach. In this way, each element was coded across the
15 intervention approaches. To be coded as required, the
element had to be specified in the intervention (e.g., the ele-
ment imitation was coded as required in the Complexity
approach given the statement, “a child is instructed to repeat
the clinician’smodel”[E. Baker & Williams, 2010, p. 109]).
Optional elements were discretionary (e.g., the element intel-
ligibility/communicative effectiveness was coded as optional
in the Nonlinear approach given the statement, “Other
goals of treatment may include general communicative
effectiveness …” [Bernhardt, Bopp, Daudlin, Edwards, &
Wastie, 2010, p. 324]). To be coded as absent indicated
that an element was not included or not mentioned in an
intervention approach (e.g., the element imitation was coded
absent in the NISI approach given the statement, “imita-
tive prompting and drill activities are not key components
for this approach”[Camarata, 2010, p. 396]).
Initially, all the researchers discussed the coding for
the intervention approaches and reached consensus on
definitions and interpretation. Next, the first two researchers
read the chapter authors’descriptions of each of the 15 inter-
vention approaches, then coded all elements as required,
optional, or absent. In Phase 2, the chapter text used as
data was expanded to include text from additional chapter
sections (viz., sections labeled Materials and Equipment
Required, Assessment and Progress Monitoring, and Case
Study; see Appendix A for a description). Coding of this
additional text by the two researchers was completed by con-
sensus for each element for each approach (1,095 element
judgments).
Reliability
Once consensus had been reached for all elements, the
first two researchers recoded two of the approaches indepen-
dently to establish reliability, yielding 96.2% agreement
for 130 data points. This level of reliability is consistent with
that reported in Dunst et al. (2011), which used a similar
methodology and coding system.
Results
The results are presented in two sections. First, we
report on the frequency with which different intervention
elements were coded as required, optional, or absent within
and across the 15 intervention approaches studied. Second,
we compare intervention approaches based on how many
elements were coded for each approach (concentration), the
percentage of optional elements to all elements comprising
an approach (flexibility), and the percentage of rare ele-
ments and omitted common elements to all elements com-
prising an approach (distinctiveness).
Overview of Elements Across Approaches
The frequency with which elements were used across all
interventions is presented in Table 2. The elements are listed
in accordance with the domain, category, and subcategory
structures of the Phonological Intervention Taxonomy.
Baker et al.: Phonological Intervention Taxonomy 7
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Figure 1. Phonological Intervention Taxonomy. The figure presented in this clinical focus article appears courtesy of the authors. Copyright
© 2017 by Elise Baker, A. Lynn Williams, Sharynne McLeod, and Rebecca J. McCauley.
8American Journal of Speech-Language Pathology •1–30
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Table 2. Element use within the Phonological Intervention Taxonomy for 15 interventions.
Domain Category Subcategory Elements
Required (score = 2)
(bold = rare
elements
a
)
Optional
(score = 1)
Absent (score = 0)
(bold = common
elements omitted
b
)
Goal Focus 1. Sound segment production 10 (67%) 2 (13%) 3 (20%)
2. Phonological processes/rules/
patterns/features/classes
6 (40%) 1 (7%) 8 (53%)
3. Phonotactics (e.g., stress,
word shape)
3 (20%) 9 (60%) 3 (20%)
4. Intelligibility/communicative
effectiveness
4 (27%) 6 (40%) 5 (33%)
5. Input processing/speech
perception
2 (13%) 1 (7%) 12 (80%)
6. Phonological awareness
and literacy
3 (20%) 3 (20%) 9 (60%)
7. Other linguistic abilities
(e.g., morphosyntax)
4 (27%) 0 (0%) 11 (73%)
Characteristics
of goal/target
8. Stimulable sounds 3 (20%) 6 (40%) 6 (40%)
9. Nonstimulable sounds 2 (13%) 7 (47%) 6 (40%)
10. Early developing sounds 2 (13%) 7 (47%) 6 (40%)
11. Later developing sounds 2 (13%) 8 (53%) 5 (33%)
12. Sounds always incorrect 2 (13%) 8 (53%) 5 (33%)
13. Sounds sometimes correct 1 (7%) 8 (53%) 6 (40%)
14. Lexical inconsistency 1 (7%) 1 (7%) 13 (87%)
15. Broader factors beyond
sound segment
11 (73%) 4 (27%) 0 (0%)
Linguistic context
of stimulus
16. Isolated speech sounds/
articulatory movements
2 (13%) 10 (67%) 3 (20%)
17. Nonwords 2 (13%) 1 (7%) 12 (80%)
18. Real words 13 (87%) 1 (7%) 1 (7%)
19. Sentences 4 (27%) 8 (53%) 3 (20%)
20. Conversation 3 (20%) 7 (47%) 5 (33%)
21. Contrastive words 5 (33%) 2 (13%) 8 (53%)
22. Written letters, words,
or sentences
4 (27%) 4 (27%) 7 (47%)
Goal progression
strategy
23. Vertical 0 (7%) 8 (53%) 7 (47%)
24. Horizontal 3 (20%) 8 (53%) 4 (27%)
25. Cyclical 3 (20%) 5 (33%) 7 (47%)
Teaching
moment
Antecedent Content of model
or instruction
26. Articulatory–phonetic 11 (73%) 1 (7%) 3 (20%)
event (clinician) 27. Phonological 14 (93%) 1 (7%) 0 (0%)
28. Metaphor 1 (7%) 3 (20%) 11 (73%)
29. Phonological awareness/
literacy
5 (33%) 4 (27%) 6 (40%)
3 (20%) 1 (7%) 11 (73%)
(table continues)
Baker et al.: Phonological Intervention Taxonomy 9
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Table 2. (Continued).
Domain Category Subcategory Elements
Required (score = 2)
(bold = rare
elements
a
)
Optional
(score = 1)
Absent (score = 0)
(bold = common
elements omitted
b
)
30. Semantic/morphologic/
syntactic
Modality of model
or instruction
31. Spoken 14 (93%) 1 (7%) 0 (0%)
32. Visual 15 (100%) 0 (0%) 0 (0%)
33. Tactile/kinesthetic 0 (0%) 5 (33%) 10 (67%)
34. Gestural 1 (7%) 3 (20%) 11 (73%)
Response
(child)
Response level 35. Imitation 10 (67%) 3 (20%) 2 (13%)
36. Spontaneous 13 (87%) 1 (7%) 1 (7%)
Response requirement 37. Verbal: Phonetic production
(speech sound/s)
3 (20%) 9 (60%) 3 (20%)
38. Verbal: Phonological production
(words +)
13 (87%) 1 (7%) 1 (7%)
39. Phonological awareness/literacy
related
5 (33%) 4 (27%) 6 (40%)
40. Nonspeech: Prearticulatory/mouth
movement
0 (0%) 2 (13%) 13 (87%)
41. Auditory/listening 8 (53%) 1 (7%) 6 (40%)
42. Gestural 1 (7%) 1 (7%) 13 (87%)
Consequent
event
(clinician)
Evaluative feedback 43. Knowledge of results (e.g.,
judgment of correct/incorrect)
12 (80%) 2 (13%) 1 (7%)
44. Knowledge of performance
(e.g., shaping)
11 (73%) 3 (20%) 1 (7%)
Reflective feedback 45. Request for the child’s
self-judgment/self-monitoring
6 (40%) 0 (0%) 9 (60%)
Responsive feedback 46. Recast/expansion 6 (40%) 1 (7%) 8 (53%)
Context Intervention
agent
47. Speech-language pathologist
(SLP)
15 (100%) 0 (0%) 0 (0%)
48. Parent 7 (47%) 8 (53%) 0 (0%)
49. Teacher 1 (7%) 9 (60%) 5 (33%)
50. Other children 0 (0%) 4 (27%) 11 (73%)
51. Other agents 0 (0%) 7 (47%) 8 (53%)
Venue 52. Clinic 15 (100%) 0 (0%) 0 (0%)
53. Home 6 (40%) 8 (53%) 1 (7%)
54. School 1 (7%) 9 (60%) 5 (33%)
Session format 55. Individual 9 (60%) 6 (40%) 0 (0%)
56. Group 1 (7%) 6 (40%) 8 (53%)
Resources 57. Paper based (e.g., books, cards) 12 (80%) 1 (7%) 2 (13%)
58. Objects 9 (60%) 2 (13%) 4 (27%)
59. Scripts 2 (13%) 0 (0%) 13 (87%)
60. Computer/technology 2 (13%) 5 (33%) 8 (53%)
Activities Type 61. Naturalistic activities 5 (33%) 4 (27%) 6 (40%)
62. Structured activities 11 (73%) 2 (13%) 2 (13%)
Social/emotional
valence
63. Challenging 2 (13%) 5 (33%) 8 (53%)
64. Fun 4 (27%) 7 (47%) 4 (27%)
(table continues)
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Table 2. (Continued).
Domain Category Subcategory Elements
Required (score = 2)
(bold = rare
elements
a
)
Optional
(score = 1)
Absent (score = 0)
(bold = common
elements omitted
b
)
Procedural
issues
Intensity 65. Session frequency 6 (40%) 9 (60%) 0 (0%)
66. Session duration 7 (47%) 8 (53%) 0 (0%)
67. Dose per session 0 (0%) 3 (20%) 12 (80%)
68. Total intervention duration 2 (13%) 6 (40%) 7 (47%)
Training 69. SLP prerequisite knowledge/
specific training requirements
1 (7%) 0 (0%) 14 (93%)
70. Non-SLP personnel prerequisite
knowledge/specific training
requirements
4 (27%) 5 (33%) 6 (40%)
Evaluation 71. Criterion-based progression 3 (20%) 3 (20%) 9 (60%)
72. Prescribed data collection 5 (33%) 10 (67%) 0 (0%)
a
Rare elements (bolded cells in Column 5) were coded as required for three or fewer approaches (Column 5) and absent by more than 50% of approaches (Column7).
b
Common elements
omitted (bolded cells in Column 7) were coded as absent for three or fewer approaches (Column 7) and required for more than 50% of approaches (Column 5).
Baker et al.: Phonological Intervention Taxonomy 11
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Goal
Focus
Across the 15 approaches, goals could focus on up
to seven different areas: (a) sound segments, (b) phonologi-
cal processes/rules/patterns/rules/features/classes, (c) phono-
tactics, (d) intelligibility/communicative effectiveness,
(e) input processing/speech perception, (f) phonological
awareness/literacy, and (g) other linguistic abilities. The
most common required goal focus was sound segments
(n= 10), whereas input processing/speech perception was
the least common goal focus (n= 2). Although no single ap-
proach incorporated all areas of focus, two approaches—
the Cycles and Psycholinguistics approaches—were coded
as addressing up to six areas.
Characteristics of Goal/Target
Eight target characteristics were examined as possi-
ble elements for each of the 15 phonological intervention
approaches. Most of these characteristics centered on
sound segments (stimulable sounds, nonstimulable sounds,
early developing sounds, later developing sounds, sounds
always incorrect, sounds sometimes correct). These char-
acteristics were often coded as optional, suggesting that
most approaches allow users considerable latitude or dis-
cretion in the characteristics of the speech segments targeted
in intervention. Other target characteristics included lexi-
cal inconsistency and broader factors. This latter target
characteristic captures factors beyond the sound segment,
such as phonotactic structures, phoneme collapses, intel-
ligibility, phonological awareness, and other linguistic
domains—individual elements specified in the category goal
focus.
Linguistic Context of Stimulus
Seven linguistic contexts were coded as possible ele-
ments: (a) isolated speech sounds or articulatory movements,
(b) nonwords, (c) real words, (d) sentences, (e) conversa-
tion, (f) contrastive words, or (g) written letters/words/
sentences. Of these, real words was the most frequently coded
required context (n= 13), whereas nonwords and isolated
speech sounds were the least frequently coded required con-
texts (n= 2). One approach (Psycholinguistics) was coded
as requiring or optionally including all linguistic con-
texts. In contrast, only two approaches were coded as requir-
ing only one linguistic context: The Speech Perception
approach was coded as requiring the use of real words,
and the NISI approach was coded as requiring the use of
conversation.
Goal Progression Strategy
The three goal progression strategies identified as
possible elements were horizontal, vertical, and cyclical. Three
approaches (Cycles, Nonlinear, and Morphosyntax ap-
proaches) were coded as requiring a cyclical progression
strategy and, three (Stimulability, Dynamic Systems, and
enhanced milieu teaching with phonological emphasis [EMT/
PE; Scherer & Kaiser, 2010]), as requiring a horizontal
strategy. For eight of the nine remaining intervention ap-
proaches, two or more goal progression strategies were
identified and coded as optional (e.g., Complexity approach
could use vertical or horizontal goal attack strategies). The
remaining intervention approach, Core Vocabulary, was
not assigned a goal progression strategy as the area of focus
was lexical consistency.
Teaching Moment
Antecedent Event
Content of model or instruction. Of the five examined
model contents (articulatory–phonetic, phonological, meta-
phor, phonological awareness and literacy, and semantic/
morphologic/syntactic), a phonological model was most
commonly coded as required (n= 14). Although other model
contents occurred less frequently, such as metaphor (n=1),
it may be that this element was incorporated in more
approaches but was not explicitly specified in the text. All
five model contents were coded as required or optional in
PACT, whereas only one model content (i.e., spoken phono-
logical model of a word) was coded as required in the Speech
Perception and NISI approaches.
Modality of model and/or instruction. Of the four
modalities we examined as possible elements (spoken, tactile/
kinesthetic, visual, gestural), spoken model was specified as
required by 14 approaches and optional by the remaining
approach (NISI). Two approaches (Stimulability, Psycho-
linguistics) specified use of all four modalities as either
required or optional.
Response
Response level. Two response levels were identified.
Spontaneous response was the most commonly coded re-
sponse level (n= 13), followed by imitation (n= 10). Ten
of the 15 approaches indicated that both spontaneous and
imitative response levels were to be used.
Response requirement. Six response requirements
were identified. Verbal production of words was the most
commonly required response from the child (n= 13), whereas
a nonspeech prearticulatory mouth movement was coded
absent for 13 approaches. Across approaches, Cycles and
PACT incorporated five of the six types of child responses
as required or optional, whereas the Speech Perception
approach and NISI only specified one type of response from
the child (viz., auditory/listening and verbal productions,
respectively).
Consequent Event
Evaluative feedback. Both types of evaluative feed-
back, knowledge of results and knowledge of performance,
were frequently coded as required (n= 12 and 11, respec-
tively). Two approaches (Stimulability, EMT/PE) indicated
optional use of both knowledge of results and knowledge
of performance, and only one approach (NISI) was coded
as not requiring either type of evaluative feedback.
Reflective feedback. Request for repair or self-judgment
was coded as required for six approaches and as not specified
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as a consequent event in the remaining nine interventions.
The six approaches that were coded as requiring use of
reflective feedback were Minimal Pairs, Multiple Opposi-
tions, Core Vocabulary, Psycholinguistics, Metaphonology,
and PACT.
Responsive feedback. Six interventions were coded
as requiring responsive feedback (Multiple Oppositions,
Stimulability, Dynamic Systems, Morphosyntax, NISI,
and EMT/PE). Of the remaining nine interventions, eight
did not require responsive feedback, and the PACT approach
indicated that use of responsive feedback was optional.
Context
Intervention Agent
Of the five different intervention agents that could
be included in an intervention (SLP, parent, teacher, other
children, other agents), SLP was coded as required across
all approaches (n= 15), with parent required for seven
approaches. Teachers were coded as required for one
approach (Core Vocabulary). If they were not coded as
required intervention agents, parents and teachers were
typically coded as optional elements. Overall, although
most approaches incorporated at least two different in-
tervention agents, two approaches (Nonlinear and NISI)
required or indicated optional use of all five possible inter-
vention agents.
Venue
Of the three possible venues (clinic, home, school),
clinic was coded as required for all approaches (n= 15),
whereas school was coded as the least specified venue (n=1;
Core Vocabulary). Across approaches, all three venues
were coded as required or optional for most (n= 11) ap-
proaches. Conversely, one approach (Speech Perception)
required just one venue (i.e., clinic). This appeared to reflect
the goal types specified by the approaches.
Session Format
Of the two session formats (individual, group), indi-
vidual therapy sessions were coded as required for eight
approaches, individual and group were coded as required
for one approach (Morphosyntax), and individual and/or
group was coded as optional for the remaining six ap-
proaches (Minimal Pairs, Multiple Oppositions, Psycho-
linguistics, Metaphonology, Nonlinear, and Dynamic
Systems).
Resources
Of the four types of resources we identified (paper-
based, objects, scripts, computer/technology), paper-based
resources, such as cards or books, was the most common
element coded as required (n= 12), whereas scripts and
computer/technology were coded as the least common
required resource (n= 2 for each). Across approaches, no
approach utilized all four types of resources. The Speech
Perception approach was coded as requiring only a single
resource (i.e., computer/technology).
Activities
Type. Of the two types of activities we examined,
structured activities were coded as required (n= 11) more
than naturalistic activities (n= 5). Both activity types were
coded as required in two approaches (Multiple Opposi-
tions, PACT). Two approaches did not include structured
activities, rather requiring naturalistic activities only (NISI
and EMT/PE).
Social/emotional valence. Fun activities were coded
as required for four approaches (PACT, Morphosyntax,
Nonlinear, Stimulability) and challenging for two ap-
proaches (Minimal Pairs, Complexity). Four approaches
(Psycholinguistics, Metaphonology, Speech Perception,
and EMT/PE) specified both elements as optional. It is
possible this one or both elements were assumed and, thus,
not included in authors’descriptions, given that informa-
tion about intervention activities being challenging or fun
was absent for eight and four approaches, respectively.
Procedural Issues
Intensity
The four elements related to intensity were dura-
tion, frequency, dose, and total intervention duration. All
approaches were coded as either required or optional for
duration and frequency. Although never coded as required,
dose was sometimes coded as an optional element (n=3;
Multiple Oppositions, Core Vocabulary, and Morpho-
syntax). It was unclear whether the absence of informa-
tion about dose for the majority of approaches (n= 12)
was indicative that a predetermined dose was not required
or that information about dose was unspecified in the
chapters.
Training
Intervention approaches only rarely specified that
training was required for either SLPs (n= 1) or for non-
SLP personnel (n= 4). In fact, six approaches (Minimal
Pairs, Multiple Oppositions, Complexity, Cycles, Stimulabil-
ity, and Nonlinear) made no mention of training. Five
approaches (Core Vocabulary, Speech Perception, Dynamic
Systems, Morphosyntax, and NISI) coded training as op-
tional for non-SLP personnel, and only one approach
(EMT/PE) required special training for SLP and non-SLP
personnel.
Evaluation
Criterion-based progression was coded as required
for three approaches (Minimal Pairs, Multiple Oppositions,
and Complexity) and optional for an additional three
approaches (Core Vocabulary, Nonlinear, Morphosyntax).
By contrast, all approaches were coded as required or op-
tional for prescribed data collection.
To summarize, 16 of the 72 elements were coded as
required for 10 or more of the approaches. Common ele-
ments included goals related to sound segments with SLPs
providing visual and spoken phonological models and re-
quiring spontaneous production of words. Feedback was
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primarily evaluative (knowledge of results and knowledge
of performance), rather than responsive or reflective. Inter-
vention was delivered by SLPs in the clinic in structured
individual sessions using paper-based resources. Conversely,
the goal elements that were rarely coded as required included
input processing, phonological awareness/literacy, and lexi-
cal inconsistency. Other elements rarely coded as required
included isolated speech sounds/articulatory movements and
nonwords as the stimulus context, the use of metaphor and
semantic/morphological/syntactic in models, using tactile/
kinesthetic and/or gestural mode for providing models,
nonspeech prearticulatory mouth movements in children’s
responses, intervention agents involving other non-SLP
personnel, school venue, group format, scripts or computer/
technology resources, and naturalistic activities. Several
subcategories were coded as required or optional less fre-
quently across approaches, which may be an artifact of
the detail included within the text by each author. These
areas included type of activities (naturalistic, structural), in-
tensity, social/emotional valence, training, and evaluation.
Overview of Approaches With Respect to
Concentration, Flexibility, and Distinctiveness
The three constructs of concentration, flexibility, and
distinctiveness were created to characterize individual ap-
proaches with respect to the numbers of elements specified
as required or optional (concentration), the percentage
of optional elements relative to the total elements com-
prising an approach (flexibility), and the percentage with
which rare elements are included and common elements
are omitted relative to the total elements comprising an
approach (distinctiveness). Together, these three measures
were used to consider the similarities and differences across
approaches.
Concentration
The total number of elements coded as required or
optional per approach, defined as concentration, is shown
in Table 1. Recall that a total of 72 elements were identi-
fied in the development of the Phonological Interventional
Taxonomy. The mean concentration of elements across
approaches was 45 elements, with 25 coded as required. As
listed in Table 1, the densest approaches (i.e., the approaches
with the largest number of elements coded as required or
optional) were Psycholinguistics and PACT, each with
59 of 72 elements (82%). Of these two approaches, PACT
had the highest number of required elements at 36. The
least dense approach was Speech Perception intervention
with 27 of 72 possible elements (37.5%), 13 of which were
coded as required. Although Speech Perception was coded
as having the smallest number of required elements, it is
important to note that this approach is always complemen-
ted with an approach targeting speech production (Rvachew
& Brosseau-Lapré, 2010) that would comprise its own set
of elements. Similarly, the Morphosyntax approach, com-
prising 42 elements, alternates with an approach targeting
speech production (Tyler & Haskill, 2010). NISI, which
focuses on intelligibility, may also be complemented with
Naturalistic Intervention for Speech Accuracy (Camarata,
2010).
Flexibility
Flexibility was defined as the proportion of elements
rated as optional relative to the total number of elements
(ratings as optional or required) per approach. The mean
flexibility across all 15 approaches was 44%, and the flexi-
bility score for each approach is in Table 1. Minimal Pairs
had a total of 48 elements, of which 26 were rated as op-
tional, yielding a flexibility score of 54%. This meant that
approximately half of the elements described in the Mini-
mal Pairs approach could be used at the clinicians’discre-
tion. The Nonlinear and Psycholinguistics approaches were
the most flexible, with flexibility scores of 62% and 58%,
respectively. Approaches with a lower proportion of elements
coded as optional included the Dynamic Systems (29%)
and Cycles approaches (32%).
Distinctiveness
To clarify what made the approaches different from
one another, we constructed a measure of distinctiveness by
examining how frequently rare elements were included and
common elements were omitted. Specifically, rare elements
were defined as required for three or fewer approaches but
absent for more than 50% of approaches; common elements
were defined as absent for three or fewer approaches but
required for more than 50% of approaches. Then, distinc-
tiveness was calculated as the following percentage: ([# of
rare elements + # of omitted common elements] / [all ele-
ments included in the intervention]) × 100. This process led
to the identification of 14 rare elements and 10 common
elements omitted. Rare elements were dispersed across 11 of
the 15 categories in the taxonomy and are shown in Table 2.
The majority of approaches (n= 14) had up to three rare
elements (average number of rare elements 1.7). By contrast,
common elements were omitted in fewer approaches (n=4).
When distinctiveness was calculated, Speech Perception was
considered the most distinctive approach with 30% of
elements being distinct, followed by NISI with 23% of ele-
ments being distinct. The majority of approaches typically
had one or two rare elements (6% of elements overall) dis-
tinguishing them from most other approaches.
Discussion
Clinicians working with children with SSD have many
choices about which intervention approach to use. As the
results from our investigation have shown, phonological
intervention approaches vary in their combination of elements
with respect to total number of elements (i.e., concentration),
proportion of optional elements (i.e., flexibility), and pro-
portion of included rare and omitted common elements
versus the total number of elements (i.e., distinctiveness).
Some approaches have more elements or are more con-
centrated than others. Most also contain rare elements un-
common to most approaches. In this discussion, we reflect
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on the findings from the development of the Phonological
Intervention Taxonomy and the description of 15 intervention
approaches using the taxonomy. We discuss the implica-
tions of the findings from this qualitative investigation with
respect to intervention research, teaching, and implemen-
tation. We also consider the limitations of our efforts and
posit directions for future research.
Reflections on the Phonological Intervention
Taxonomy and Intervention Elements
We began this process of better understanding the
diversity of phonological interventions for children with
SSD, proposing that one view of intervention approaches
is as a bundle of elements designed for use as a collective
package—a theoretical view similar to that reflected in the
treatment theory that guided the development of the RTT
(Turkstra et al., 2016). Empirical support for interventions
is also grounded in the additive, synergistic, and antagonistic
effect of the package, not the individual elements. That
is, the overall effect of intervention is not always as simple
as the sum of the elements (additive). The effect can be
greater than the sum of the elements, as elements support
one another (synergistic). It could also be less than the sum
of the elements, as elements counteract one another (antag-
onistic). An appreciation for the diversity of choice of
approaches, however, necessitates a reductionist rather than
a holistic approach to understanding the elements compris-
ing interventions. In this study, we used authors’(usually
the developers’) descriptions of 15 empirically supported in-
terventions to identify and describe elements of intervention
a posteriori. Using content analysis, we identified 72 ele-
ments and arranged them into a hierarchical framework
comprising four broad domains and 15 categories and nine
subcategories. We described each of the 15 interventions
with respect to the required or optional inclusion or absence
of each element.
In the introduction to this clinical focus article, we
speculated about the degree to which the many approaches
to intervention differ. The finding that, on average, the in-
terventions were coded as containing 45 elements, with the
majority of approaches containing three or fewer rare ele-
ments, suggests that there are similarities. It remains to be
determined whether some elements are common because
they are essential, reminiscent of traditional practice, or are
playing an, as yet, unidentified role. In the general concept
of treatment theories incorporated in the RTT described
by Turkstra et al. (2016), two types of active ingredients are
postulated: those that are essential to the treatment theory
being instantiated and those that are simply present in the
intervention. Applying this to the Phonological Intervention
Taxonomy, developers of approaches might explicate their
intervention by identifying essential (active) elements crucial
to improving children’s speech intelligibility (e.g., specific
target characteristics) while acknowledging the presence of
other active elements (e.g., social/emotional valence, evalu-
ative feedback) in conjunction with the theoretical perspec-
tives motivating those elements.
A good starting point may be to better understand
how the presence of one or more rare elements within a
bundle of common elements or, indeed, the absence of a
common element in an approach distinguishes one approach
from another, not just in terms of procedures but also in
terms of their efficacy. Developers’different realization of
similarly coded elements also requires consideration. The
element of an “auditory/listening”response requirement is
a good example. For instance, the listening tasks included
in the Speech Perception approach (Rvachew & Brosseau-
Lapré, 2010) are not the same as the listening tasks used in
the Psycholinguistics approach (Stackhouse & Pascoe, 2010),
which, again, are not the same as those used in the Cycles
approach (Prezas & Hodson, 2010). In our taxonomy, their
respective listening tasks were all coded under the same ele-
ment classification (domain: teaching moment; category:
child’s response; subcategory: response requirement, element:
auditory/listening). This point highlights the descriptive
nature of the Phonological Intervention Taxonomy. It is not
meant to serve as a rigid framework limiting our under-
standing of what constitutes interventions but a platform
for facilitating discussion and richer understandings about
the elements that make up interventions, how interventions
compare, and, especially, how those elements impact the
performance of the intervention.
Implications for Intervention Research
In this study, intervention elements were identified
aposteriori. The resulting Phonological Intervention Taxon-
omy revealed that many elements can make up interven-
tions. The coding process also suggested that some elements
needed to be more explicitly specified in their developer’s
descriptions. For instance, across the 15 approaches, 12 did
not provide sufficient information about dose per session
(an aspect of the intensity category). However, in reality, the
rarity of this element may in fact be an artifact of either
insufficient empirical knowledge related to this element or
the unlikely idea that a prescribed dose per session is not
crucial (E. Baker, 2012) and, therefore, not currently a
required or even optional element. Such results highlight
the importance of clarity in intervention descriptions (includ-
ing what elements are required, optional, or intentionally
absent), given that descriptions are an important medium
for knowledge translation and replication. One way forward
to further clarifying what is known about individual inter-
ventions could be to interview developers about the ideas
and elements underscoring their approaches, compile the
empirical evidence, and observe developers demonstrating
their approach. In this way, a rich compendium of a priori
and a posteriori knowledge from multiple sources could ad-
vance clinical practice.
Assuming that the elements of the intervention are
known and explicit, it would be important that research
determine the necessity, timing, and individual, synergistic,
or possible antagonistic effect of elements comprising inter-
ventions. Such research would help to distil the active ele-
ments of an intervention, improving both effectiveness and
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efficiency. Future research could also consider when and
how elements (particularly optional elements) are to be
used and how they might be tailored to meet the needs of
individual children. For instance, Major and Bernhardt
(1998) identified that client characteristics influenced the
necessity of phonological awareness activities in interven-
tion. Similarly, Rvachew and Brosseau-Lapré (2010) have
reported that many, but not all, children benefit from
speech perception training prior to intervention focused
on production practice. Another valuable line of inquiry
would be to examine practicing clinicians’implementation
of interventions, including the interventions considered
in the current investigation, other empirically supported
approaches, and clinicians’own eclectic practice (e.g.,
Lancaster, Keusch, Levin, Pring, & Martin, 2010) to explore
if, when, and how clinicians tailor interventions to individual
children. The better we understand the elements that com-
prise interventions and the effect of those elements, the bet-
ter clinicians will be able to select, tailor, and implement
interventions to optimize outcomes for children.
Given that phonological impairment is one type of
SSD, future research could apply the a posteriori method
from this study to other types of interventions, particularly
interventions for motor speech disorders, such as child-
hood apraxia of speech and childhood dysarthria. In this
way, richer insight into the similarities and differences
between phonological and motor-based interventions could
advance our understanding about important required ver-
sus optional and absent elements across interventions for
different types of SSD. Given that the majority of phono-
logical interventions include speech production practice
and that there is an inextricable nexus between phonology
and motor speech abilities (Fey, 1985), this research could
help clarify the role of the principles of motor learning and
ensuing elements, such as the optimal conditions of practice
(e.g., amount, distribution, schedule) and feedback (e.g.,
frequency, type, timing; Maas et al., 2008) in phonological
interventions.
Implications for Teaching and Implementation
One of the chief intents of the Phonological Interven-
tion Taxonomy was to increase the transparency of inter-
vention descriptions for children with SSD, as a means of
improving clinical training and implementation. The fact
that the intervention approaches differed with respect to
element concentration, flexibility, and distinctiveness raises
questions about how approaches can best be taught. Given
that approaches contain a combination of common and
rarer elements, it may be helpful for students to become
familiar with common elements advancing to rare ele-
ments, as they build their knowledge and expertise about
individual approaches. Potentially, this could also foster
an understanding about similarities and differences between
approaches. Similarly, given that some approaches contain
more elements than others, it may be beneficial for stu-
dents to learn about approaches containing fewer elements,
before learning about denser interventions containing multiple
elements. Interventions that are denser and/or contain more
rare elements may require more explicit instruction and
demonstration for SLPs to develop expertise in a particular
intervention. The Phonological Intervention Taxonomy,
therefore, facilitates hypotheses that might guide future
studies supporting clinical training.
In light of the diversity across interventions, study-
ing the demands on SLPs to faithfully implement different
approaches might fruitfully be examined with respect to
the concentration, flexibility, and distinctiveness of elements
or even the identity of individual elements, some of which
may pose lower demands than others. It may be that faith-
ful implementation of approaches with more elements,
greater flexibility of elements, and/or more unique elements
requires more experience, greater manualization, or other
supports for implementation. The multitasking inherent dur-
ing intervention sessions suggests that frequent and repeti-
tive implementation of specific elements (i.e., experience)
may reduce the task demand enabling faithful implementa-
tion. SLPs may also use a particular approach over another
simply because it is easier and more enjoyable to imple-
ment. As yet, we know little about what is required to
faithfully implement the diverse range of phonological inter-
ventions (Justice, 2010). Research examining expert and
novice clinicians may provide insight into the resources, skills,
and attitudes required for successful knowledge transfer
and implementation.
Given that eclectic practice is used by some SLPs
(Brumbaugh & Smit, 2013; McLeod & Baker, 2014), re-
search examining the elements that comprise eclectic prac-
tice may better inform an understanding not only of the
efficacy of such practice but also of the motivations under-
lying departures from faithful implementation of empiri-
cally supported interventions. Do SLPs engage in eclectic
practice because the elements that comprise specific empiri-
cally supported approaches have not been made sufficiently
explicit or because the methods comprising these approaches
have not been disseminated or taught to SLPs in a man-
ner that they can faithfully implement? Perhaps, novice SLPs
engage in eclectic practice as they learn to implement
and become more familiar with the multiple elements that
comprise an approach. Conversely, perhaps expert SLPs
engage in eclectic practice by using their clinical expertise
to modify elements known to be part of an approach
and /or implement optional elements according to client
need. Departures from fidelity may have much to teach us
about the cognitive demands associated with intervention
delivery.
Limitations
The methods we used to describe interventions then
examine them with respect to concentration, flexibility, and
distinctiveness are not without limitations. The process
was complex and required a level of inference on the part
of the coders. The data for the content analysis and review
used chapter authors’descriptions of interventions within
Williams et al. (2010). Although a second source was used
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to ensure that saturation of elements had been achieved,
future research could address the match between the
Phonological Intervention Taxonomy and the wider body
of literature on each approach (e.g., books, clinical re-
sources, published research, and video examples of imple-
mentation). In particular, information is needed that
bridges the distance between the ways in which interven-
tions are methodically described and the ways in which
they are actually implemented, both in research and clini-
cal settings.
In addition, this review was based on 15 phonological
intervention approaches, whereas E. Baker and McLeod
(2011) identified 46 distinct phonological intervention ap-
proaches with 23 described in more than one publication.
The approaches that were selected for the current review had
empirical evidence and were all described by the authors
using the same template (see Appendix A). It is acknowl-
edged, however, that other approaches may include additional
elements. Furthermore, interventions that target motor
speech difficulties were not included in the current review.
Selected principles of motor learning (e.g., high vs. low fre-
quency feedback) were not identified within the 15 phono-
logical interventions, so this descriptor of clinician feedback
was not included in the Phonological Intervention Taxon-
omy. As noted, subsequent research could address the
match between this framework and the other phonological
and motor speech approaches.
Finally, this taxonomy now sits within the field of
speech-language pathology at a time when taxonomies are
being developed in other areas (e.g., Turkstra et al., 2016;
Van Stan et al., 2015), yet to date, no coordination of
development efforts has been pursued. It is likely that the
largely behavioral interventions used in voice, rehabilitation,
SSD in children, and other areas of intervention in speech-
language pathology have much in common with each other
and that the promotion of coordinated efforts might limit
an unhelpful burgeoning of alternative terminologies—a
concern noted by Van Stan et al. (2015) in their incorpora-
tion of a dictionary/thesaurus in their taxonomy. On a wider
scale, still, the proliferation of taxonomies across many
related fields (e.g., behavioral health, rehabilitation, edu-
cation) suggests the value of even broader interdisciplinary
efforts.
Conclusion
This study demonstrated the importance of think-
ing about intervention approaches both as a whole and in
terms of the individual elements comprising them. The
Phonological Intervention Taxonomy represents a step in
describing the elements within and across phonological
interventions. Further research is needed to clarify all ele-
ments that comprise individual approaches, distil the active
elements, and identify strategies that best facilitate faith-
ful replication and implementation to enhance SLPs’selec-
tion of intervention approaches and implementation in
accordance with developers’intentions.
Acknowledgment
The first and third authors acknowledge support from an
Australian Research Council Discovery Grant DP130102545.
References
* = Chapters reporting phonological intervention approaches that
were included in the study.
Abraham, C., & Michie, S. (2008). A taxonomy of behavior change
techniques used in interventions. Health Psychology, 27(3),
379–387.
Abry, T., Hulleman, C. S., & Rimm-Kaufman, S. E. (2015). Using
indices of fidelity to intervention core components to identify
program active ingredients. American Journal of Evaluation,
36(3), 320–338.
American Psychological Association. (2010). Publication manual of
the American Psychological Association (6th ed.). Washington,
DC: Author.
Andrews, G., Guitar, B., & Howie, P. (1980). Meta-analysis of the
effects of stuttering treatment. Journal of Speech and Hearing
Disorders, 45, 287–307.
*Baker, E. (2010). Minimal pair intervention. In A. L. Williams,
S. McLeod, & R. J. McCauley (Eds.), Interventions for speech
sound disorders in children (pp. 41–72). Baltimore, MD:
Brookes.
Baker, E. (2012). Optimal intervention intensity. International
Journal of Speech-Language Pathology, 14(5), 401–409.
Baker, E., & McLeod, S. (2011). Evidence-based practice for chil-
dren with speech sound disorders: Part 1 narrative review.
Language, Speech, and Hearing Service in Schools, 42(2),
102–139.
*Baker, E., & Williams, A. L. (2010). Complexity approaches to
intervention. In A. L. Williams, S. McLeod, & R. J. McCauley
(Eds.), Interventions for speech sound disorders in children
(pp. 95–116). Baltimore, MD: Brookes.
Baker, M. (2015). First results from psychology’s largest repro-
ducibility test. Nature. Retrieved from https://doi.org/10.1038/
nature.2015.17433
*Bernhardt, B. M., Bopp, K. D., Daudlin, B., Edwards, S. M., &
Wastie, S. E. (2010). Nonlinear phonological intervention.
In A. L. Williams, S. McLeod, & R. J. McCauley (Eds.), Inter-
ventions for speech sound disorders in children (pp. 315–332).
Baltimore, MD: Brookes.
*Bowen, C. (2010). Parents and Children Together (PACT) inter-
vention. In A. L. Williams, S. McLeod, & R. J. McCauley
(Eds.), Interventions for speech sound disorders in children
(pp. 407–426). Baltimore, MD: Brookes.
Brumbaugh, K. M., & Smit, A. B. (2013). Treatment children
ages 3–6 who have speech sound disorder: A survey. Language,
Speech, and Hearing Services in Schools, 44, 306–319.
Camarata, S. M. (1995). A rationale for naturalistic speech intelligi-
bility intervention. In M. E. Fey, J. Windsor, & S. F. Warren
(Eds.), Language intervention: Preschool through elementary
years (Communication and language intervention series, Vol. 5,
pp. 63–84). Baltimore, MD: Brookes.
*Camarata, S. (2010). Naturalistic intervention for speech intelli-
gibility and speech accuracy. In A. L. Williams, S. McLeod,
& R. J. McCauley (Eds.), Interventions for speech sound dis-
orders in children (pp. 381–406). Baltimore, MD: Brookes.
Des Jarlais, D. C., Lyle, C., Crepaz, N., & the TREND Group.
(2004). Improving the reporting quality of nonrandomized
evaluations of behavioral and public health interventions: The
Baker et al.: Phonological Intervention Taxonomy 17
Downloaded From: https://ajslp.pubs.asha.org/ by a ReadCube User on 05/05/2018
Terms of Use: https://pubs.asha.org/ss/rights_and_permissions.aspx
TREND Statement. American Journal of Public Health, 94,
361–366.
Dijkers, M. P. (2015). Reporting on interventions: Issues and
guidelines for rehabilitation researchers. Archives of Physical
Medicine and Rehabilitation, 96(6), 1170–1180.
Dijkers, M. P., Hart, T., Whyte, J., Zanca, J. M., Packel, A.,
& Tsaousides, T. (2014). Rehabilitation treatment taxonomy:
Implications and continuations. Archives of Physical Medicine
and Rehabilitation, 95(Supplement),S45–S54.
Dingfelder, H. E., & Mandell, D. S. (2011). Bridging the research-
to-practice gap in autism intervention: An application of dif-
fusion of innovation theory. Journal of Autism and Developmental
Disorders, 41, 597–609.
*Dodd, B., Holm, A., Crosbie, S., & McIntosh, B. (2010). Core
vocabulary intervention. In A. L. Williams, S. McLeod, &
R. J. McCauley (Eds.), Interventions for speech sound disorders
in children (pp. 117–136). Baltimore, MD: Brookes.
Dunst, C. J., Raab, M., & Trivette, C. M. (2011). Characteristics
of naturalistic language intervention strategies. Journal of
Speech-Language Pathology and Applied Behavior Analysis,
11(5), 8–16.
Eifert, G., Schulte, D., Zvolensky, M. J., Lejuez, C. W., & Lau,
A. W. (1997). Manualized behavior therapy: Merits and chal-
lenges of manualized behavior therapy: The debate. Behavior
Therapy, 28, 499–509.
Embry, D. D., & Biglan, A. (2008). Evidence-based kernels:
Fundamental units of behavioral influence. Clinical Child
and Family Psychology Review, 11, 75–113.
Fey, M. E. (1985). Articulation and phonology: Inextricable con-
structs in speech pathology. Human Communication Canada,
9(1), 7–16.
Fey, M. E., & Finestack, L. H. (2009). Research and develop-
ment in child language intervention: A five-phase model. In
R. G. Schwartz (Ed.), Handbook of child language disorders
(pp. 513–531). New York, NY: Psychology Press.
Guitar, B. E., & McCauley, R. J. (2010). Treatment of stuttering:
Established and emerging interventions. Baltimore, MD: Wolters-
Kluwer Publishers.
Hammer, C. S. (2011). The importance of participant demo-
graphics. American Journal of Speech-Language Pathology,
20(4), 261.
Hatch, J. A. (2002). Doing qualitative research in education settings.
Albany, NY: State University of New York.
Hegde, M. N. (1985). Treatment procedures in communication dis-
orders. San Diego, CA: College-Hill Press.
*Hesketh, A. (2010). Metaphonological intervention: Phonological
awareness. In A. L. Williams, S. McLeod, & R. J. McCauley
(Eds.), Interventions for speech sound disorders in children
(pp. 247–274). Baltimore, MD: Brookes.
Hoffman, P. R., & Norris, J. A. (2010). Dynamic systems and
whole language intervention. In A. L. Williams, S. McLeod, &
R. J. McCauley (Eds.), Interventions for speech sound disorders
in children (pp. 333–354). Baltimore, MD: Brookes.
Hoffmann, T. C., Glasziou, P. P., Boutron, I., Milne, R., Perera, R.,
Moher, D., .. . Michie, S. (2014). Better reporting of interven-
tions: Template for Intervention Description and Replication
(TIDieR) checklist and guide. BMJ, 348, g1687.
Ioannidis, J. P. A. (2005). Contradicted and initially stronger
effects in highly cited clinical research. Journal of the American
Medical Association, 294(2), 218–228.
Justice, L. M. (2010). When craft and science collide: Improv-
ing therapeutic practices through evidence-based innovations.
International Journal of Speech-Language Pathology, 12(2),
79–86.
Kaderavek, J. N., & Justice, L. M. (2010). Fidelity: An essential
component of evidence-based practice in speech-language
pathology. American Journal of Speech-Language Pathology,
19(4), 369–379.
Lancaster, G., Keusch, S., Levin, A., Pring, T., & Martin, S. (2010).
Treating children with phonological problems: Does an eclectic
approach to therapy work? International Journal of Language &
Communication Disorders, 45(2), 174–181.
Lincoln, Y. S., & Guba, E. G. (1985). Naturalistic inquiry. Thousand
Oakes, CA: Sage.
Ludemann, A., Power, E., & Hoffmann, T. C. (2017). Investigat-
ing the adequacy of intervention descriptions in recent speech-
language pathology literature: Is evidence from randomized
trials useable? American Journal of Speech-Language Pathol-
ogy, 26(2), 443–455.
Maas, E., Robin, D. A., Austermann Hula, S. N., Freedman, S. E.,
Wulf, G., Ballard, K. J., & Schmidt, R. A. (2008). Principles of
motor learning in treatment of motor speech disorders American
Journal of Speech-Language Pathology, 17(3), 277–298.
Major, E. M., & Bernhardt, B. H. (1998). Metaphonological skills
of children with phonological disorders before and after phono-
logical and metaphonological intervention. International Journal
of Language & Communication Disorders, 33(4), 413–444.
Makel, M. C., & Plucker, J. A. (2014). Facts are more important
than novelty: Replication in the educational sciences. Educational
Researcher, 43(6), 304–316.
Malouf, D. B., & Taymans, J. M. (2016). Anatomy of an evidence
base. Educational Researcher, 45, 454–459.
McCartney, E., Boyle, J., Bannatyne, S., Jessiman, E., Campbell, C.,
Kelsey, C., ... O’Hare, A. (2004). Becoming a manual occupa-
tion? The construction of a therapy manual for use with lan-
guage impaired children in mainstream primary schools.
International Journal of Language & Communication Disorders,
39(1), 135–148.
McCauley, R. J., & Demetras, M. J. (1990). The identification of
language impairment in the selection of specifically language
impaired subjects. Journal of Speech and Hearing Disorders,
5, 468–475.
McCauley,R.J.,&Fey,M.E.(2006). Introduction. In R. J.
McCauley & M. E. Fey (Eds.), Treatment of language dis-
orders in children (pp. 1–20). Baltimore, MD: Brookes.
McCauley, R. J., Fey, M. E., & Gillam, R. B. (2017). Introduc-
tion. In R. J. McCauley, M. E. Fey, & R. B. Gillam (Eds.),
Treatment of language disorders in children (2nd ed., pp. 1–22).
Baltimore, MD: Brookes.
McIntyre, L. L., Gresham, F. M., DiGennaro, F. D., & Reed, D. D.
(2007). Treatment integrity of school-based interventions with
children in the Journal of Applied Behavior Analysis 1991–2005.
Journal of Applied Behavior Analysis, 40, 659–672.
McLeod, S., & Baker, E. (2014). Speech-language pathologists’
practices regarding assessment, analysis, target selection, inter-
vention, and service delivery for children with speech sound
disorders. Clinical Linguistics & Phonetics, 28(7–8), 508–531.
McLeod, S., & Baker, E. (2017). Children’s speech: An evidence-based
approach to assessment and intervention. Boston, MA: Pearson.
*Miccio, A. W., & Williams, A. L. (2010). Stimulability intervention.
In A. L. Williams, S. McLeod, & R. J. McCauley (Eds.), Inter-
ventions for speech sound disorders in children (pp. 179–202).
Baltimore, MD: Brookes.
Michie,S.,Abraham,C.,Eccles,M.P.,Francies,J.J.,Hardeman,W.,
& Johnsonton, M. (2011). Strengthening evaluation and imple-
mentation by specifying components of behaviour change
interventions: A study protocol. Implementation Science, 6, 10.
https://doi.org/10.1186/1748-5908-6-10
18 American Journal of Speech-Language Pathology •1–30
Downloaded From: https://ajslp.pubs.asha.org/ by a ReadCube User on 05/05/2018
Terms of Use: https://pubs.asha.org/ss/rights_and_permissions.aspx
Michie, S., Fixsen, D., Grimshaw, J. M., & Eccles, M. P. (2009).
Specifying and reporting complex behaviour change inter-
ventions: The need for a scientific method. Implementation
Science, 4, 4–40.
Moher, D., Schulz, K. R., Altman, D., & the CONSORT Group.
(2001). The CONSORT Statement: Revised recommenda-
tions for improving the quality of reports of parallel-group
randomized trials. Journal of the American Medical Associa-
tion, 185(15), 1987–1991.
Müller-Merbach, H. (2007). Kant’s two paths of knowledge crea-
tion: Apriorivs. a posteriori.Knowledge Management Research
and Practice, 5(1), 64–65.
Muma, J. R. (1993). The need for replication. Journal of Speech
and Hearing Research, 36(5), 927–930.
Open Science Collaboration. (2015). Estimating the reproducibility
of psychological science. Science, 349(6251), aac4716. https://
doi.org/10.1126/science.aac4716
Plutchik, R. (1983). Foundations of experimental research (3rd ed.).
New York, NY: Harper & Row.
Prelock, P., & McCauley, R. J. (2012). Treatment of autism spec-
trum disorders: Evidence-based intervention strategies for com-
munication and social interventions. Baltimore, MD: Brookes.
*Prezas, R. F., & Hodson, B. W. (2010). The cycles phonologi-
cal remediation approach. In A. L. Williams, S. McLeod, &
R. J. McCauley (Eds.), Interventions for speech sound disorders
in children (pp. 137–158). Baltimore, MD: Brookes.
*Rvachew, S., & Brosseau-Lapré, F. (2010). Speech perception in-
tervention. In A. L. Williams, S. McLeod, & R. J. McCauley
(Eds.), Interventions for speech sound disorders in children
(pp. 295–314). Baltimore, MD: Brookes.
Sanetti, L. M. H., & Kratochwill, T. (2009). Toward developing
a science of treatment integrity: Introduction to the special
series. School Psychology Review, 38(4), 445–459.
*Scherer, N. J., & Kaiser, A. P. (2010). Enhanced milieu teach-
ing with phonological emphasis for children with cleft lip and
palate.InA.L.Williams,S.McLeod,&R.J.McCauley
(Eds.), Interventions for speech sound disorders in children
(pp. 427–450). Baltimore, MD: Brookes.
Schultz, K. F., Altman, D. G., Moher, D., & the CONSORT
Group. (2010). CONSORT 2010 Statement: Updated guide-
lines for reporting parallel group randomized trials. Annals of
Internal Medicine, 152(11), 726–732.
*Stackhouse, J., & Pascoe, M. (2010). Psycholinguistic inter-
vention. In A. L. Williams, S. McLeod, & R. J. McCauley (Eds.),
Interventions for speech sound disorders in children (pp. 219–246).
Baltimore, MD: Brookes.
Swift, W. (1918). Speech defects in school children.Cambridge,MA:
Riverside Press.
Turkstra, L. S., Norman, R., Whyte, J., Dijkers, M. P., & Hart, T.
(2016). Knowing what we’re doing: Why specification of treat-
ment methods is critical for evidence-based practice in speech-
language pathology. American Journal of Speech-Language
Pathology, 25(2), 164–171.
*Tyler, A. A., & Haskill, A. M. (2010). Morphosyntax interven-
tion. In A. L. Williams, S. McLeod, & R. J. McCauley (Eds.),
Interventions for speech sound disorders in children (pp. 355–377).
Baltimore, MD: Brookes.
Van Stan, J. H., Roy, N., Awan, S., Stemple, J., & Hillman, R. E.
(2015). A taxonomy of voice therapy. American Journal of
Speech-Language Pathology, 24(2), 101–125.
Ward-Horner, J., & Sturmey, P. (2010). Component analyses
using single-subject experimental designs: A review. Journal
of Applied Behavior Analysis, 43(4), 685–704.
Warren, S. F., Fey, M. E., & Yoder, P. J. (2007). Differential
treatment intensity research: A missing link to creating opti-
mally effective communication interventions. Mental Retarda-
tion and Developmental Disabilities Research Reviews, 13(1),
70–77.
Whyte, J., Dijkers, M. P., Hart, T., Zanca, J. M., Packel, A.,
Ferraro, M., & Tsaousides, T. (2014). Development of a
theory-driven rehabilitation treatment taxonomy: Concep-
tual issues. Archives of Physical Medicine and Rehabilitation,
95(Suppl. 1), 524–532.
*Williams, A. L. (2010). Multiple oppositions intervention. In
A. L. Williams, S. McLeod, & R. J. McCauley (Eds.), Inter-
ventions for speech sound disorders in children (pp. 73–93).
Baltimore, MD: Brookes.
Williams, A. L., McLeod, S., & McCauley, R. J. (Eds.). (2010).
Interventions for speech sound disorders in children. Baltimore,
MD: Brookes.
World Health Organization. (2001). ICF: International classifica-
tion of functioning, disability and health. Geneva, Switzerland:
Author.
World Health Organization. (2007). International classification of
functioning, disability and health: Children and youth version:
ICF-CY. Geneva, Switzerland: Author.
Yin, R. K. (2011). Qualitative research from start to finish.
New York, NY: Guilford.
Baker et al.: Phonological Intervention Taxonomy 19
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Appendix A
Instructions Provided to Authors of Chapters in Williams et al. (2010) for Describing Speech Sound Interventions That Were
Used in the Two Phases of the Current Analysis
PHASE 1: Topics for describing the requirements and components of interventions for speech sound disorders that were
used in the first phase of analysis
1. Practical Requirements (1–2 pages)
a) Nature of sessions (Include frequency and length of sessions as well as whether the sessions are individual,
group, school-based, home-based, etc.)
b) Personnel (Identify both the primary clinician and other participants, training required of personnel involved, any
materials that are required, and so on. Please also include discussion of how parents/families are used and
trained. Additionally, specify the nature of involvement of participants beyond the clinician and child (e.g., the
clinician, parents, peers, siblings, teachers). In the case of parent-administered interventions, the clinician’s
role should be specified.)
2. Key Components (5–8 pages)
a) Nature of goals (e.g., broad goals of intervention and basis of target selection)
b) Goal attack strategies (e.g., sequential, simultaneous, cyclical)
c) Description of activities (e.g., procedural or operational description of activities within which the goals are addressed)
d) Materials and equipment required
PHASE 2: Topics that were added for the second phase of analysis
3. Target Populations and Assessments for Determining Intervention Relevance*
a) Assessment methods (i.e., used to establish the appropriateness of the intervention for the individual child. Where
assessment methods associated with determining the appropriateness of the approach to the child are particularly
detailed, use citations to supplement a brief overview of those methods.)
4. Theoretical Basis*
a) Level of consequences being addressed (i.e., Is the intervention targeting a functional limitation directly or the
social skill, activity, or social role restrictions that result from it? Interest in this distinction arises from work by the
World Health Organization [2001, 2007].)
b) Target areas of intervention (i.e., describe whether solely focusing on speech output or broader domains, such
as perception, literacy, morphosyntax, cognition, etc.)
5. Assessment and Progress Monitoring to Support Decision Making (1–2 pages)
Recommended assessment techniques and data collection used for decision making within the method, such as
whether progress is being made, when changes should be made to the treatment plan, and when treatment should be
terminated
*Additional information was provided by the chapter authors under these headings; however, this additional information was
not used in the current analysis.
20 American Journal of Speech-Language Pathology •1–30
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Appendix B (p. 1 of 10)
Definition and Examples of Elements Comprising the Phonological Intervention Taxonomy
Domain Category Subcategory Element Definition of element Example
a
Goal Focus 1. Sound segment
production
Goals focus on acquisition of sound
segments, either as singletons
and/or segments comprising
consonant clusters.
•“intervention targets are typically
consonants or consonant clusters”
(E. Baker & Williams, 2010, p. 108:
Complexity)
2. Phonological
processes,
patterns, rules,
features, and/or
sound classes
Goals focus on phonological
processes (e.g., stopping of
fricatives), phonological patterns
(e.g., anterior/posterior contrasts),
phonemecollapseruleset(e.g.,
voiceless obstruents and stop
clusters collapsed to [t]), or
phonological features and classes
(e.g., continuants, major class
features).
•“phonological patterns are presented
and recycled as needed”(Prezas
& Hodson, 2010, p. 145: Cycles)
•“the multiple opposition approach
addresses several target sounds
from a phoneme collapse or rule
set”(Williams, 2010, p. 84: Multiple
Oppositions)
3. Phonotactics Goals focus on phonological abilities
beyond the segment (e.g., stress,
syllable, and word shapes, between
word processes).
•“New individual prosodic structures
could entail new word lengths in
syllables, new word and/or phrasal
stress patterns, and/or new word
shapes…” (Bernhardt, Bopp, Daudlin,
Edwards, & Wastie, 2010, p. 324:
Nonlinear)
4. Intelligibility/
communicative
effectiveness
Goals focus on overall intelligibility
and successful communication.
•“goals are related to increases in
functional intelligibility”(Camarata,
2010, p. 396: NISI)
•“goalsoftreatmentmayinclude
general communicative effectiveness”
(Bernhardt et al., 2010, p. 324:
Nonlinear)
5. Input
processing/
speech
perception
Goals focus on input processing,
such as speech perception
and/or word recognition, as
opposed to production.
•“SAILS [Speech Assessment and
Interactive Learning System]
addresses the child’s speech
perception abilities”(Rvachew &
Brosseau-Lapré, 2010, p. 302: Speech
Perception)
•“targeting a weak aspect of the model
(e.g., auditory discrimination of a
specific contrast)”(Stackhouse & Pascoe,
2010, p. 237: Psycholinguistics)
6. Phonological
awareness
and literacy
Goals targeting one or more literacy-
related abilities, such as phonemic
awareness, letter/sound knowledge.
•“goals of treatment may include…
phonological awareness, such as
the skills in identifying rhymes,
onsets, segments, or syllable and
rhythm patterns”(Bernhardt et al.,
2010, p. 324: Nonlinear)
•“incorporate explicit links between
sounds and letters”(Stackhouse &
Pascoe, 2010, p. 239: Psycholinguistics)
7.
(table continues)
Baker et al.: Phonological Intervention Taxonomy 21
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a(Continued).
Domain Category Subcategory Element Definition of element Example
a
Other linguistic
abilities
Goals addressing broader linguistic
or communicative abilities (e.g.,
morphosyntax, vocabulary, social–
conversational/pragmatic abilities,
such as responsiveness, and
ability to initiate and maintain
conversation).
•“increase the likelihood that the child
will initiate and maintain communicative
interaction”(Scherer & Kaiser, 2010,
p. 439: EMT/PE)
•“thoughtfully selected morpheme goals”
(Tyler & Haskill, 2010, p. 365–366:
Morphosyntax)
Characteristics of
goal/target
8. Stimulable
sounds
Speech sound that a child is able to
imitate when provided with auditory,
visual, and/or tactile cues (Williams,
McLeod, & McCauley, 2010, p. 618).
•“targets for which a child shows readiness
and stimulability should be selected”
(Prezas & Hodson, 2010, p. 146: Cycles)
9. Nonstimulable
sounds
Speech sound that a child is unable to
imitate when provided with auditory,
visual, and/or tactile cues (Williams
et al., 2010, p. 618).
•“nonstimulable sounds are considered to
be more complex and worth prioritizing
over stimulable sounds”(E. Baker &
Williams, 2010, p. 104: Complexity)
10. Early
developing
sounds
Speech sounds that are relatively
earlier developing (e.g., /p, b, m, n/).
•“for some children target selection is
conservative and traditional, respecting
developmental expectations and most
phonological knowledge”(Bowen, 2010,
p. 421: PACT)
11. Later developing
sounds
Speech sounds that are relatively later
developing (e.g., /l, s, ɹ,θ/).
•“intervention targets are typically consonants
or consonant clusters that are…later
developing”(E. Baker & Williams, 2010,
p. 108: Complexity)
12. Sounds always
incorrect
Speech sounds that are not used by a
child and, as such, always in error
in words (e.g., key /ki/ →[ti]; bucket
/bʌkǝt/ →[bʌtǝt]; bike /baɪk/ →[baɪt]).
•“intervention targets are typically consonants
or consonant clusters that are…consistently
in error”(E. Baker & Williams, 2010, p. 108:
Complexity)
13. Sounds
sometimes
correct
Sounds that a child has some productive
phonological knowledge of as
evidenced by occasional use in
words (e.g., key /ki/ said as [ti]
on five occasions and [ki] once).
•“targets should be included that are
produced correctly some of the time”
(Miccio & Williams, 2010, p. 191:
Stimulability)
14. Lexical
inconsistency
Inconsistency is evident when a word
is pronounced differently on at least
one of three trials (e.g., feet [fi],
[bit], [bi]).
•“for children who make inconsistent
errors”(Dodd, Holm, Crosbie, &
McIntosh, 2010, p. 123: Core Vocabulary)
(table continues)
Appendix B (p. 2 of 10)
Definition and Examples of Elements Comprising the Phonological Intervention Taxonomy
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a(Continued).
Domain Category Subcategory Element Definition of element Example
a
15. Broader factors
beyond sound
segment
Factors influencing goal/target broader
than or beyond the sound segment,
which could include phonotactic
structures (e.g., consonant clusters,
weak syllables, stress patterns),
groups of phonemes collapsed within
a rule set, intelligibility, phonological
awareness abilities, and other
linguistic domains.
•“multiple oppositions approach addresses
several target sounds from a phoneme
collapse, or rule set, within larger
contrastive treatment stimuli”(Williams,
2010, p. 84: Multiple Oppositions)
•“syllableness …is a target for children
who speak in monosyllables”(Prezas
& Hodson, 2010, p. 148: Cycles)
•“the broad goal…is to increase the child’s
awareness of word forms…with the aim
of facilitating speech change and literacy
acquisition”(Hesketh, 2010, p. 263:
Metaphonology)
Linguistic
context
16. Isolated speech
sounds or
articulatory
movements
Production of specific speech sounds
in isolation (e.g., [s:::]) or in a syllable
(e.g., [bǝ]) or specific mouth movement.
•“sounds are taught in isolation (e.g.,
[s:::::]) or CV contexts (e.g., [kʌkʌkʌ])
for stops and glides”(Miccio & Williams,
2010, p. 190: Stimulability)
•“limited activities to direct oral airflow,
such as limited use of low resistance
blowing toys”(Scherer & Kaiser, 2010,
p. 438: EMT/PE)
17. Nonwords Nonwords (i.e., nonsense words) that
may or may not be assigned lexical
meaning during intervention.
•“NSWs [nonsense words] serve as the
treatment word stimuli”(E. Baker &
Williams, 2010, p. 109: Complexity)
18. Real words Real words that may or may not be
meaningful to the child.
•“the multiple oppositions approach
incorporates picture stimuli of real words,
although occasionally nonsense words
are used”( Williams, 2010, p. 88: Multiple
Oppositions)
19. Sentences Production of a target speech sound
or phonological pattern beyond the
single-word level—phrases and
sentences.
•“consistency of production is extended
to sentence frames and spontaneous
speech”(Dodd et al., 2010, p. 130: Core
Vocabulary)
20. Conversation Production of a targeted speech
production skill (e.g., specific sound,
syllable shape, stress pattern,
intelligibility) or other linguistic ability
during conversational speech.
•“The later phases (Phase 3 and Phase 4)
place more emphasis on the contrastive
function of the target sounds within
communication and conversati onal
contexts”(Williams, 2010, p. 87: Multiple
Oppositions)
21. Contrastive
words
Two or more words used in a
contrastive way to highlight the
function of phonemes.
•“challenged to produce a contrast
between the word pairs in order to
be understood”(E. Baker, 2010, p. 61:
Minimal Pairs)
(table continues)
Appendix B (p. 3 of 10)
Definition and Examples of Elements Comprising the Phonological Intervention Taxonomy
Baker et al.: Phonological Intervention Taxonomy 23
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a(Continued).
Domain Category Subcategory Element Definition of element Example
a
22. Written letters,
words, or
sentences
Written letters/graphemes, words
and/or sentences used to target
phonological awareness/literacy
goal.
•“…graphemes will be used and mentioned
more and more as children become more
familiar with literacy at school”(Hesketh,
2010, p. 265: Metaphonology)
•“letter-sound relationships in the text”
(Hoffman & Norris, 2010, p. 347: Dynamic
Systems)
Goal
progression
strategy
23. Vertical Intervention targeting one phoneme
or one specific pattern/process
per session until predetermined
performance criteria has been met
(i.e., sequential progression).
•“intervention goals have most frequently
been implemented within a sequential
goal attack strategy (one phoneme or
pattern at a time)”(E. Baker, 2010, p. 60:
Minimal Pairs)
24. Horizontal Intervention targeting two or more
phonemes from different classes
or different patterns/processes
within a session (i.e., simultaneous
progression).
•“a horizontal goal attack strategy…is
incorporated with the stimulability
intervention program, as all consonants
are addressed within each therapy
session”(Miccio & Williams, 2010,
p. 190: Stimulability)
25. Cyclical A range of goals are worked on within
a period of time but not at the same
time (e.g., goals change weekly)
and may be re-revisited for another
period of time according to need.
•“deficient phonological patterns from
prior cycles are recycled as many times
as needed”(Prezas & Hodson, 2010,
p. 145: Cycles)
Teaching
moment
Antecedent
event
(clinician)
Content of
model or
instruction
26. Articulatory–
phonetic
Clinician provides a model of the target
phone/speech sound, syllable structure
or stress pattern, and/or instruction
(cues/prompts) about how to articulate
the phonetic target. The modality of
the model may vary (e.g., spoken,
visual, tactile–kinesthetic, gestural).
•“the /ɹ/ is modeled for the child”(Prezas
& Hodson, 2010, p. 149: Cycles)
•“phonetic placement cues are used to
shape the child’s production of the target
sound”(Miccio & Williams, 2010, p. 195:
Stimulability)
27. Phonological Clinician provides a model and/or
information about the phonological
target, focusing a child’s attention
on the function of phonemes.
•“The SLP shows the child the picture for
each word, saying, for example, ‘This
is a ring, we wear it on our finger. This
is a wing on a bird.’” (E. Baker, 2010,
p. 61: Minimal Pairs)
28. Metaphor Clinician provides a verbal analogy,
such as /ʃ/ is the quiet sound,
to make abstract phonological
or phonetic aspects of a target
easier to understand.
•“the growling /ɹ/ sound”(E. Baker, 2010,
p. 62: Minimal Pairs)
29. Phonological
awareness/
literacy
Clinician provides phonological
awareness and/or literacy-related
instruction.
•“Tell me the first sound in…Find me all
the words beginning with…” (Hesketh,
2010, p. 264: Metaphonology)
•“the clinician would explain that the name
Joseph has two syllables”(Dodd et al.,
2010,p.130:CoreVocabulary)
(table continues)
Appendix B (p. 4 of 10)
Definition and Examples of Elements Comprising the Phonological Intervention Taxonomy
24 American Journal of Speech-Language Pathology •1–30
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a(Continued).
Domain Category Subcategory Element Definition of element Example
a
30. Semantic/
morphologic/
syntactic
Clinician provides a model, instruction,
cloze task, forced choice, or focused
stimulation for a semantic, morphologic,
and/or syntactic target.
•“Modeling and mand-model procedures
provide a means of structuring a child’s
responses to facilitate the use of target
vocabulary”(Scherer & Kaiser, 2010,
p. 440: EMT/PE)
•“the clinician may present a forced choice
prompt such as, ‘Tell me what Jenny
does with the flower seeds. She plants
them or she waters them?’” (Tyler &
Haskill, 2010, p. 368: Morphosyntax)
Modality of
model
and/or
instruction
31. Spoken Clinician provides verbal instruction,
description, and/or auditory model
of targeted skill (e.g., phonetic,
phonological, phonological
awareness, semantic/morphologic).
•“clinicians should provide information
about the plan, requiring children to
generate their own plan for the word”
(Dodd et al., 2010, p. 131: Core
Vocabulary)
•“Adult says, “key rhymes with…” (Bowen,
2010, p. 416: PACT)
32. Visual Clinician provides a visual referent
(e.g., pictures, objects, written
words) relevant to the target skill.
•“holds the morphophonic vocabulary card
for lick below the written word”(Hoffman
& Norris, 2010, p. 349: Dynamic Systems)
•“the clinician presents each character card
one at a time”(Miccio & Williams, 2010,
p. 195: Stimulability)
33. Tactile/
kinesthetic
Clinician provides a manual cue to
physically assist the child in the
articulation of a target sound (e.g.,
clinician gently draws client’s
cheeks forward to facilitate rounding
of the lips to articulate /ʃ/; use of a
tongue depressor to touch the child’s
alveolar ridge to highlight placement
for /l / ). In con trast to gestura l
modality, tactile–kinesthetic modality
involves physical touch of the child’s
mouth or manual guidance (Hegde,
1985). This cue could be provided
before or during the child’s response.
•“Pluggingthenosemayassistthechildto
direct the airstream through the mouth.”
(Scherer & Kaiser, 2010, p. 438: EMT/PE)
34. Gestural Clinician provides a physical movement
or gesture with their hands to highlight
a specific articulatory or phonological
characteristic of the target (e.g., long–
short movement with hands to highlight
fricative vs. stop; tapping the number
of syllables in a word; using hands to
model the placement of the tongue
relative to the palate; using hands to
move objects together to symbolize
two consonants in a cluster).
•“using stress and intonation paired with
phys ical prompts of the new contrasts to
be learned (e.g., contrasting long and
short arm movements coinciding with
the production of fricative and stop
sounds)”(Williams, 2010, p. 85: Multiple
Oppositions)
•“Two linked-up characters move together,
each pronouncing their part of the cluster:
[s][n]”(Bernhardt et al., 2010, p. 325:
Nonlinear)
(table continues)
Appendix B (p. 5 of 10)
Definition and Examples of Elements Comprising the Phonological Intervention Taxonomy
Baker et al.: Phonological Intervention Taxonomy 25
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a(Continued).
Domain Category Subcategory Element Definition of element Example
a
Response
(child)
Response
level
35. Imitation Child imitates or repeats the clinician’s
production of targeted skill.
•“During the imitation phase, a child
is instructed to repeat the clinician’s
model”(E. Baker & Williams, 2010,
p. 109: Complexity)
36. Spontaneous Child’s production is said without an
auditory model in the clinician’s
antecedent utterance.
•“During the spontaneous phase, the
child is instructed to provide the same
treatment words independently without
a model”(E. Baker & Williams, 2010,
p. 109: Complexity)
Response
requirement
37. Verbal: phonetic
production
(speech
sound/s)
Child articulates a specific speech
sound.
•“the child imitates the prolonged [l]”
(Hoffman & Norris, 2010, p. 349:
Dynamic Systems)
•“Articulation work if necessary to allow
the child to produce the target sounds
in isolation and in simple words”(Hesketh,
2010, p. 265: Metaphonology)
38. Verbal:
phonological
production
(words +)
Child produces a targeted phonological
skill in a word, phrase, or sentence.
•“A foundational component is that the
child produces spontaneous word
attempts followed by an adult recast that
models correct production at the word
level”(Camarata, 2010, p. 396: NISI)
39. Phonological
awareness/
literacy
Child identifies a particular letter or
engages in a phonological awareness
task, such as producing rhyming
words, or segmenting/blending at the
phonemic level. The response could
be verbal and/or nonverbal (e.g.,
pointing, matching, sorting).
•“silent sorting of 10 cards into rhyming
pairs”(Bowen, 2010, p. 417: PACT)
•“Commonly used tasks requiring awareness
of word-initial phonemes include…initial
phoneme isolation (e.g., ‘Tell me the first
sound in…’)”(Hesketh, 2010, p. 264:
Metaphonology)
40. Nonspeech:
Prearticulatory/
mouth movement
Child produces a mouth movement prior
to articulating or in anticipation of
articulating a specific speech sound.
•“/l/isfairlyeasytoelicitafterthechildhas
been taught to click his or her tongue
independent of jaw movement”(Prezas
& Hodson, 2010, p. 149: Cycles)
41. Auditory/listening The child listens and responds via
pointing, selecting, or manipulating
a picture or object, or making a
judgment about clinician’s prior
utterance. Child’s response requires
metalinguistic awareness (e.g.,
pointing to pictures said by clinician;
right/wrong judgment about a
clinician’s speech) that differs from
routine phonological awareness/
literacy tasks.
•“the child hears the recording of a word”
(Rvachew & Brosseau-Lapré, 2010,
p. 306: Speech Perception)
•“You be the teacher and tell me if I say
these words the right way or the wrong
way”(Bowen, 2010, p. 417: PACT)
42. Gestural Use of specific gestures or hand
movements that may or may not
accompany attempted production
of targeted speech skill.
•“Clinician and child take turns producing
the sound and associated [hand] motion
of the character”(Miccio & Williams,
2010, p. 194: Stimulability)
(table continues)
Appendix B ( p. 6 of 10)
Definition and Examples of Elements Comprising the Phonological Intervention Taxonomy
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a(Continued).
Domain Category Subcategory Element Definition of element Example
a
Consequent
event
(clinician)
Evaluative
feedback
43. Knowledge
of results
Child is given feedback regarding the
accuracy of response (i.e., correct/
incorrect) that may include praise
or encouragement.
•“Like, you got it!”(Hoffman & Norris, 2010,
p. 350: Dynamic Systems)
•“That’sright,soap has an [s]…” (Hesketh,
2010, p. 267: Metaphonology)
44. Knowledge of
performance
Child is given feedback about why their
response was correct or incorrect. For
example, if the child’s response was
incorrect, this instruction might tell
the child how to articulate the target
speech sound in the word via placement
cues and/or provide the child with
information about what makes a
particular speech sound contrastive
relative to another speech sound.
Knowledge of performance could be
used to shape a child’s response
toward a more accurate response.
•“the clinician can…explicitly explain that
the word differed and how it differed”(Dodd
et al., 2010, p. 131: Core Vocabulary)
•“occasionally, phonetic placement cues
are used to shape the child’s production
of the target sound”(Miccio & Williams,
2010, p. 195: Stimulability)
Reflective
feedback
45. Request for
the child’s
self-judgment/
self-monitoring
The child is instructed to judge, self-
monitor, and/or repair his or her
own utterances containing speech
production errors.
•“feedback is delayed using semantic
confusion and wrong clinician models
to encourage self-monitoring”(Williams,
2010, p. 87: Multiple Oppositions)
•“fixed-up-one routine”(Bowen, 2010,
p. 417: PACT)
Responsive
feedback
46. Recast/expansion Recast is the repetition of a child’s
utterance, using appropriate
phonological, grammatical, syntactic
forms (Camarata, 1995); expansion is
an utterance that adds information
or expands upon a child’s utterance.
•“speech recasts are those recasts that
provide correct phonological information
in response to a child’sincorrect
production”(Scherer & Kaiser, 2010,
p. 438: EMT/PE)
•“the clinician is encouraged to respond
with a simple expansion recast (repetition
of the child’s utterance but using the
correct grammatical form) or with a
‘growth recast’…emphasizing the correct
adult form in a new complete sentence
that expands on the child’s original
utterance”(Tyler & Haskill, 2010, p. 369:
Morphosyntax)
Context Intervention
agent
47. Speech-language
pathologist (SLP)
Qualified SLP. •Assessment and intervention “should be
implemented by a certified SLP”(Prezas
& Hodson, 2010, p. 146: Cycles)
48. Parent Child’s parent or caregiver. •“The personnel involved in PACT are
the child, primary caregiver(s), and the
speech-language pathologist (SLP)”
(Bowen, 2010, p. 417: PACT)
49. Teacher Child’s teacher constitutes a trained
early childhood, special education,
or classroom teacher.
•“child’sfamilyandteacher…both
must be involved from the outset of
intervention”(Dodd et al., 2010, p. 128:
Core Vocabulary)
(table continues)
Appendix B (p. 7 of 10)
Definition and Examples of Elements Comprising the Phonological Intervention Taxonomy
Baker et al.: Phonological Intervention Taxonomy 27
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a(Continued).
Domain Category Subcategory Element Definition of element Example
a
50. Other children Other children include siblings, cousins,
friends, or peers.
•“parents and siblings have participated
in intervention”(Miccio & Williams, 2010,
p. 189: Stimulability)
51. Other agents Others could include untrained personnel,
teachers’aids, paraprofessionals, and
SLP assistants.
•“can be delivered by assistants or parents”
(Stackhouse & Pascoe, 2010, p. 234:
Psycholinguistics)
Venue 52. Clinic Clinic is the SLP’s routine work location,
such as a community health center,
school clinic (not including classroom),
hospital, university teaching clinic, or
private practice setting.
•“session can be completed in clinic…”
(Camarata, 2010, p. 394: NISI)
•“university phonology clinics”(Prezas
& Hodson, 2010, p. 146: Cycles)
53. Home Home refers to the location where the
child lives.
•“session can be conducted in the
clinic, home, and classroom settings”
(Camarata, 2010, p. 394: NISI)
54. School School setting may include early
childhood (e.g., preschool),
elementary, middle, or high school
classroom environment.
•“designed to be implemented in early
childhood, elementary school, or clinical
settings”(Tyler & Haskill, 2010, p. 365:
Morphosyntax)
Format 55. Individual Intervention provided one-to-one
between child and intervention
agent (clinician, caregiver, or
paraprofessional).
•“the intervention is provided individually”
(Rvachew & Brosseau-Lapré, 2010,
p. 304: Speech Perception)
56. Group Intervention provided to two or more
children by one or more intervention
agents.
•“the morphosyntax approach is structured
to include one individual and one small-
group session per week”( Tyler & Haskill,
2010, p. 365: Morphosyntax)
Resources 57. Paper based
(e.g., books,
cards)
Paper-based materials includes
books, cards, information handouts,
pamphlets or letters for parents,
activity sheets, probe lists, analysis
forms, data collection sheets, and
homework instructions.
•“two large boxes of 1,800 picture cards
involving four sets of 450 different images
and 550 line-drawn worksheets”(Stackhouse
& Pascoe, 2010, p. 171: Psycholinguistics)
58. Objects Items used in intervention, such as toys,
board games, props for pretend play,
art and craft items, and motivating
rewards, such as stickers and stamps.
•“table top games such as lotto, posting
cards in a letterbox, card games, or
‘fishing’for cards”(Stackhouse &
Pascoe, 2010, p. 172: Psycholinguistics)
59. Scripts Scripts are examples of dialogue
between a clinician and a child
that guides the therapeutic
conversation.
•“detailed scripts for use during
different elicitation activities”(Tyler &
Haskill, 2010, p. 369: Morphosyntax)
60. Computer/
technology
Technology used during intervention
sessions such as laptop or desktop
computers, amplification devices,
headphones, audio and/or video-
recording devices.
•‘stimuli should always be presented to the
child through good quality headphones”
(Rvachew & Brosseau-Lapré, 2010, p. 306:
Speech Perception)
(table continues)
Appendix B (p. 8 of 10)
Definition and Examples of Elements Comprising the Phonological Intervention Taxonomy
28 American Journal of Speech-Language Pathology •1–30
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a(Continued).
Domain Category Subcategory Element Definition of element Example
a
Activities Type 61. Naturalistic
activities
Naturalistic activities involve play within
a social communicative context. The
environment may be strategically
arranged and/or the interacti on may
be child or clinician directed. Naturalistic
activities do not include games.
•“this is a child-led approach…the clinician
should set up the environment in such
a manner that the child will naturally
attempt to communicate”(Camarata,
2010, p. 394: NISI)
62. Structured
activities
Structured activities are typically preset
clinician-directed tasks or games. Such
activities may have a predetermined
dose (e.g., 100 production practice
trials). Activities may be sequenced
hierarchically, such that completion
of one activity is contingent upon
commencing another.
•“Using the five target words, the child
is instructed to name each picture
without a model…This step continues
until the child achieves 50% accuracy
independently producing the target
words in at least 50 trials”(E. Baker,
2010, p. 62: Minimal Pairs)
Social/
emotional
valence
63. Challenging An aspect of intervention (specifically
with respect to producing a particular
speech sound or experiencing a
breakdown in communication) may
be challenging or somewhat frustrating
for a child for motivating the child
to communicate.
•“if a child has the phonetic ability to
produce the word, then the frustration
sometimes experienced by children
when confronted with the homonomy
in their speech might be minimized
using the perception-production
approach”(E. Baker, 2010, p. 63:
Minimal Pairs)
64. Fun Aspects of intervention are designed
for the child to experience fun
and enjoyment.
•“props, costumes, wands, and a warped
sense of fun-ology”(Bernhardt et al.,
2010, p. 326: Nonlinear)
Procedural
issues
Intensity
b
65. Session frequency How often intervention sessions are
scheduled per unit of time, typically
per week.
•“one individual and one small-group
session per week”( Tyler & Haskill, 2010,
p. 365: Morphosyntax)
66. Session duration The period of time of an intervention
session, typically measured in
minutes or hours.
•“the child’s exposure to SAILS lasted no
longer than 15 minutes in any given
session”(Rvachew & Brosseau-Lapré,
2010, p. 305: Speech Perception)
67. Dose per session The number of times an element (e.g.,
production of a targeted phonological
skill in a word) or a teaching episode
containing a combination of active
elements occurs per session (Warren,
Fey, & Yoder, 2007).
•“sessions would typically consist of 20
trials of each of the five target words…
totaling 100 trials”(E. Baker, 2010, p. 62:
Minimal Pairs)
•“clinicians aim to provide, at minimum,
40 correct (non contrasting or erroneous)
examples of the targeting form”( Tyler &
Haskill, 2010, p. 367: Morphosyntax)
(table continues)
Appendix B (p. 9 of 10)
Definition and Examples of Elements Comprising the Phonological Intervention Taxonomy
Baker et al.: Phonological Intervention Taxonomy 29
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a(Continued).
Domain Category Subcategory Element Definition of element Example
a
68. Total intervention
duration
The total period of intervention
measured in time (e.g., weeks,
months, years) or total numbers
of sessions (e.g., 21 sessions)
required or recommended to treat
SSD in children.
•“a clinician should not expect to exceed
16 half-hour sessions”(Dodd et al., 2010,
p. 129: Core Vocabulary)
Procedural
issues
Training 69. SLP prerequisite
knowledge/
specific training
requirements
Authors of an approach indicate that
additional training is required beyond
professional training needed to qualify
as an SLP. The training may be either a
structured course leading to certification
to use an approach, or informal training,
supervision, or practice.
•“It is recommended that clinicians administer
EMT/PE procedure with three children
in order to gain sufficient experience
with procedures to optimize training
effectiveness and enhance credibility
with parents”(Scherer & Kaiser, 2010,
p. 436: EMT/PE)
70. Non-SLP
personnel
prerequisite
knowledge/
specific training
requirements
Authors of an approach indicate that
non-SLP personnel require training to
use the approach. The training may
be either a structured course with
predetermined content and sequence
or unstructured informal training with
a clinician.
•“well-defined EMT training sequence
for parents that takes 20–36 sessions
(depending on parent pretreatment skills)
to reach criterion on all components of
the program”(Scherer & Kaiser, 2010,
p. 436: EMT/PE)
Evaluation 71. Criterion-based
progression
An approach has a predetermined
sequence of stages, and specific
criteria need to be met to progress from
one stage to another. Pr ogression
may be explicit (e.g., must achieve
70% accuracy) or less strict and
subject to clinician’sdiscretion.
•“A training criterion is specified for
changing from imitation to spontaneous
production in Phase 2, which is 70%
accuracy across two consecutive
training sets”(Williams, 2010, p. 87:
Multiple Oppositions)
72. Prescribed
data collection
Child’s progress is to be evaluated
using a prescribed data collection
schedule, detailing the type and
frequency of data to be collected.
•“probes may be taken at the end of
a session or on a weekly schedule”
(Hoffman & Norris, 2010, p. 350:
Dynamic Systems)
Note. NISI = naturalistic intervention for speech intelligibility; EMT/PE = enhanced milieu teaching with phonological emphasis; PACT = Parents and Children Together; SSD =
speech sound disorders.
a
Typically, one example is provided per ingredient. Where an ingredient could be exemplified in more than one way, additional examples are provided.
b
Intensity parameters (dose,
session duration, session frequency, total intervention duration) on the basis of Warren et al. (2007).
Appendix B (p. 10 of 10)
Definition and Examples of Elements Comprising the Phonological Intervention Taxonomy
30 American Journal of Speech-Language Pathology •1–30
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