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http://oncology.thelancet.com Vol 9 May 2008
485
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“…each potential subject must be adequately informed
of the aims, methods…anticipated benefi ts and potential
risks of the study and the discomfort it may entail. The
subject should be informed of the right to abstain from
participation in the study or to withdraw consent to
participate at any time without reprisal. After ensuring
that the subject has understood the information, the
physician should then obtain the subject’s freely given
informed consent, preferably in writing”.
Ethics guidelines for scientifi c research that involves
human beings have been founded on these important
principles.5 An “informed-consent doctrine” gradually
evolved that was consistent with these guidelines and
legal precedents.6 A US court case of Cobbs vs Grant7
noted that the doctrine of informed consent is “anchored”
in four postulates: fi rst, patients are generally ignorant of
medicine; second, patients have a right to control their
body and decide about medical treatment; third, consent
to treatment must be informed to be eff ective; and fourth,
Improvement of informed consent and the quality of
consent documents
Michael Jeff ord, Rosemary Moore
Guidelines on informed consent intend to protect patients and promote ethical research conduct. To give informed
consent, individuals should understand the purpose, process, risks, benefi ts, and alternatives to research (or a
proposed clinical intervention) and make a free, voluntary decision about whether to participate. Many participants
have incomplete understanding of various features of clinical trials. Issues associated with the length, format, and
language of documents for written informed consent are common. Here, we analyse the written consent form,
particularly in the context of clinical research, and the discussions that take place between clinician or investigator
and patient. We review strategies to improve consent forms, particularly the use of plain language. Recommendations
are made on discussions between investigator and patient to improve participant comprehension and satisfaction
with the informed-consent process.
Introduction
Guidelines on informed consent intend to protect
patients and promote ethical research conduct through
full explanation of a proposed treatment, including any
possible harms, and through the requirement that people
freely consent (fi gure).
In the research setting, the idea of written informed
consent dates from at least 1900, when Walter Reed
obtained written consent from patients in his research
on yellow fever in Cuba.1 The practice of obtaining
informed consent in clinical settings has been done for
centuries, founded partly on perceived obligations
derived from the Hippocratic oath. To some extent, the
practice of informed consent in clinical care and in the
research setting have evolved separately, leading to
increased regulation in the research setting.
An important event in the codifi cation of informed
consent occurred in the USA in 1914 when Justice
Cardozo laid down the basic principle that has shaped
US law on informed consent and aff ected developments
elsewhere. The principle is that: “every human being of
adult years and sound mind has a right to determine
what should be done with his own body”.2
The Nuremberg Code was developed in 1947 after
human experimentation by Nazi doctors and the trial of
those responsible. This Code established a set of principles
and guidelines for the ethical conduct of clinical research
and was a foundation for future guidelines.
In the clinical setting, the term “informed consent”
arose in the USA in 1957. It shifted emphasis from
medical paternalism towards that of a duty to respect
patient autonomy. Californian law created an “informed-
consent standard”, stating that the nature, con-
sequences, harms, benefi ts, risks, and alternatives of a
treatment was the information needed by an ordinary
person to make a “reasonable” decision about its
acceptance or rejection.3
The World Medical Association Declaration of
Helsinki in 19644 established worldwide ethical
principles for medical research that involved human
participants:
Lancet Oncol 2008; 9: 485–93
Division of Haematology and
Medical Oncology, Peter
MacCallum Cancer Centre, VIC,
Australia (M Jeff ord PhD);
Freelance editor and writer
(R Moore)
Correspondence to:
Dr Michael Jeff ord, Division of
Haematology and Medical
Oncology, Peter MacCallum
Cancer Centre, VIC 8006,
Australia
Michael.Jeff ord@petermac.org
Figure: Consent discussions between patients and investigators or clinicians are crucial for patient
understanding
Reprinted with permission of The Cancer Council, New South Wales, Australia.
486
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patients depend on their physicians for truthful
information and must trust them. These postulates refer
to clinical treatment, but also apply in the research
setting.
Main principles of informed consent
Informed consent has two main aims: fi rst, to respect
and promote participants’ autonomy; and second, to
protect them from potential harm. Provision of inform-
ation in an understandable way lends support to both
these aims. Furthermore, guidelines promote ethical
conduct of research by establishing a standard and by
refl ecting community expectations. Patients need to
understand the diagnosis, prognosis, nature and purpose
of the intervention, alternatives, risks, and benefi ts—
these are minimum requirements for genuine informed
consent. Participant satisfaction with the consent process
is also a desirable outcome.
International guidelines for research that involves
human beings include the International Conference on
Harmonisation (ICH) Guideline for Good Clinical
Practice.8 Country-specifi c guidelines also inform clinical
research (eg, the Australian National Statement on
Ethical Conduct in Human Research9 and the US
National Institutes of Health Guidelines for the Conduct
of Research Involving Human Subjects10).
Ethics committees or institutional review boards are
required to review and approve the process of obtaining
informed consent and the written information for
prospective participants to ensure that these guidelines
are followed.
Clinical care and clinical research: similarities
and diff erences
Respect for patient autonomy and protection from harm
are paramount in clinical care and research settings.
Patients need information to make informed decisions.
Reasons for a potential intervention and the potential
negative eff ects should be explained to the patient in an
understandable way.
However, clinical care and clinical research diff er. The
main aim of clinical care is to benefi t a patient. By
contrast, the main aim of research is to gain new
knowledge; benefi ts from such research are reaped
mainly by future patients.11 Many clinical trials are
reasonable therapeutic options. However, clinical
research might have a risk of additional side-eff ects.
New treatments might be associated with unknown or
theoretical risks. In this circumstance, there might be a
greater need to tell participants about these potential
side-eff ects.
Thus, the standard for informed consent in clinical
care or research might diff er depending on the context or
level of risk. In practice, clinical research is more tightly
controlled by regulatory codes and has greater oversight
by ethics committees or institutional review boards
compared with informed consent in clinical care.
Issues with the consent process
Emphasis on disclosure
Current practice in obtaining informed consent seems to
have been shaped by emphasis on the legal duty of
disclosure, particularly in the research setting. Consent
is seen as an action, concluded by signing a form.
However, informed consent needs not only disclosure
and a signature, but also promotion of participants’
understanding of the research project and the voluntary
nature of their decision to participate.12
The written informed-consent document (ie, consent
form) is an important part of the requirement to disclose
and advise participants of the details of a proposed trial.
Although the form has been said to give “legal and
symbolic documentation of an agreement to participate”,13
the length and complexity of informed-consent
documents hinder participant understanding.14 Viewing
the consent form mainly as a legal document tends to
hinder attempts to create reader-friendly documents:
“many sponsors and institutions appear to view them
primarily as a legal instrument to protect them against
litigation”.15
Poor participant understanding
For participants, signing of the consent form is meant to
indicate their agreement to participate in the trial and
confi rm that they understand the aim and risks of the
trial and their participation in it. However, this agreement
and confi rmation might only be symbolic: signing does
not always represent understanding. Patients might have
incomplete or incorrect understanding of matters
relevant to an informed decision to join a clinical
trial.14,16–33
In a cross-sectional survey34 of participants in clinical
trials of cancer treatments, Joff e and colleagues used a
validated measure of “quality of informed consent”. They
found that 186 (90%) of 207 respondents were satisfi ed
with the informed-consent process and considered
themselves well informed. However, many were unaware
of particular features of trials, including the unproven
nature of the treatment, the uncertainty of benefi ts to
themselves, or the main aim of trials to benefi t future
patients.29 In Australia, we found high levels of satisfaction
with the decision to participate in clinical trials, but again,
substantial problems in understanding.14
Inadequate explanation
Sometimes, features of trials are not discussed adequately
and patients might not have the opportunity to ask
questions. For example, in audiotaped discussions in
which consent was sought for participation in a
randomised study, the word “randomisation” was used in
only 62% of discussions and patient understanding
checked in only 17% of discussions.35 Although the word
“randomisation” might not be appropriate, the idea is
important and patient understanding should be checked
in all situations.
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A study36 of paediatricians’ explanations and parents’
understanding of randomisation in trials of leukaemia in
childhood recorded that physicians explained random-
isation in 83% of discussions and a consent form was
presented during 95% of discussions. However, only 50%
of parents understood randomisation.36 In audiotaped
consultations in which informed consent was sought,
patients rarely received complete information to make a
decision and physicians rarely checked patients’
preferences for the type and amount of information.37
Although all patients should understand the fundamental
idea of a proposed inter vention, some might desire
further information that might be excessive for others.
Physicians might be both the patient’s treating doctor
and trial investigator, which might create a situation in
which doctors inappropriately direct patients towards
trial involvement or limit full disclosure. Potential confl ict
of interest is a serious concern, although full discussion
is beyond the scope of our review. Nevertheless, this dual
relation might contribute to inadequate disclosure. In a
survey30 of 412 members of the Swedish Society of
Oncology, 45% of doctors thought that patients might not
participate if they were adequately informed. In a
randomised study,38 Simes and colleagues showed that
total disclosure of all relevant information, rather than an
individual approach at the discretion of the doctor, was
associated with less willingness to agree to randomised
treatment; however, the strategy led to better patient
understanding.
Emanuel and colleagues5 suggest “to enrol individuals
in clinical research without their authorization is to treat
them merely as a means to purposes and ends they may
not endorse and deny them the opportunity to choose
what projects they will pursue.” Consent forms need to
advise of all reasonable alternatives to joining a trial,
including, for example, the possibility of not pursuing
further anticancer treatment, but receiving best
supportive care that includes optimum palliative care.
The written consent form: readability and
comprehension
Written consent is needed for almost all studies. For
more than 25 years, researchers have noted that consent
forms might be written inappropriately.15,39,40
In the US Department of Health and Human Services,
consent forms are required to be “in language
understandable to the subject or representative”.40 The
ICH guideline recommends use of oral and written
language that is “as non-technical as practical and…
understandable to the subject”. The US National Institutes
of Health recommend writing that is understandable at
the reading level of eighth grade or lower at school.10
Although material for patient information might call
for a reading-comprehension ability that is between 10th
and 14th grade in US schools,41,42 patients in public
hospitals might have an average reading comprehension
of around 6th grade.42 Informed-consent forms fare little
better: reading levels might be as high as grade 11.40
Grossman and colleagues noted that only 6% of 137
consent forms had readability at or below 8th grade using
the Flesch Kincaid formula. In an analysis of 107 consent
forms from cancer clinical trials, none was written at or
below 8th grade reading level and only 11% were below
10th grade.15
Almost half of US adults read at or below 8th grade
level.43,44 Australians are likely to have similar literacy
levels: a national literacy and numeracy survey noted that
half the population were likely to have substantial
diffi culty with written materials used in everyday life.45
A person’s reading-comprehension level might be
several grades lower than the last grade level they
completed at school. Self-reported education levels do
not accurately measure health literacy.44,46 Consent forms
and other material for health education should be written
at least three grade levels lower than the average
educational level of the target population.46
Plain language
Plain language (commonly called plain English) is
straightforward and easy to understand. Advocates have
called for its use in government, legal, and medical
documents since the 1970s, when plain-English
movements arose in the UK and the USA, and then
worldwide (panel 1).
In non-clinical-trial settings, information written in
plain language assists in decision making about medical
treatments,47 strengthens intentions to implement clinical
guidelines, increases positive feelings towards the
guidelines, and leads to perceived greater control using
the guidelines.48
In clinical trials, simplifi ed information appeals to
patients.49 It is associated with decreased anxiety about
consent and increased satisfaction with the informed-
consent document.31
Modifi cation of consent forms
Various studies have looked at improving the readability
of the consent form. Some have concluded that
understanding might be improved if the consent form is
easy to read.50–54 Others suggest that understanding and
recall might be improved if care is taken in reading the
consent form16,23 and if suffi cient time is allowed to read
them.21,55 Short consent forms might also be useful.13,15,51
Panel 1: Websites about plain language
These websites (accessed Feb 15, 2008) can give advice and
examples on many principles of plain language:
www.askoxford.com/betterwriting/plainenglish/
www.plainlanguage.gov
www.plainlanguagenetwork.org
www.health.gov/communication/literacy/plainlanguage/
www.plainenglish.co.uk
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Enhanced and simplifi ed print versions might benefi t
people with poor reading skills.56
Simplifi cation of consent forms to improve readability
might be part of the answer, but not the whole solution.
Several studies31,49 have noted positive fi ndings from
simplifying consent forms, but these do not always
include improved comprehension.
Coyne and colleagues31 did a randomised comparison
(n=207) of an easy-to-read consent form with that of a
standard consent form. They postulated that the
modifi ed form would lead to higher patient compre-
hension and satisfaction, lower anxiety, and higher
patient accrual compared with the standard form.
Patients who were assigned the easy-to-read consent
form showed signifi cantly lower anxiety to giving
consent and higher satisfaction than did those assigned
the standard form. However, comprehension and state
anxiety (anxiety that is triggered by events or situations,
as opposed to trait anxiety, which is the tendancy of a
person to show anxious behaviour) did not diff er
between groups.
Davis and colleagues49 postulated that a simplifi ed
consent form would be less intimidating and more-
easily understood by individuals with poor to marginal
reading skills than a standard consent form. Participants
were mostly healthy and were asked to consider a
hypothetical clinical trial. They were asked to read
either a standard consent form (written at 16th grade
level) or a simplifi ed form (written at 7th grade level).
Participants were interviewed to assess their attitudes
towards, and comprehension of, the standard form and
then were given the alternate consent form and asked
which they preferred and why. Overall, participants
preferred the modifi ed, simpler form. Most considered
this simplifi ed form easier to read than the standard
form. However, the level of understanding generated by
both forms was similar. Importantly, this study did not
assess patient preference and understanding in the
context of a real trial—the participants did not have
cancer and did not need to make a decision about trial
participation.49
Flory and Emanuel57 did a systematic review of studies
that were designed to improve trial participants’
understanding of information disclosed in the
informed-consent process. They reviewed 30 eligible
studies of 42 trials. Interventions to improve under-
standing were categorised into fi ve groups: multimedia;
enhanced consent form; extended discussion; test or
feedback; and miscellaneous. 12 trials of multimedia
interventions (two in a cancer setting) showed that they
commonly did not improve under standing. Of the
15 trials with enhanced consent forms, six showed
signifi cantly improved understanding, whereas nine
did not; one of the trials enrolled patients with cancer.31
Extended discussion between study staff and participants
signifi cantly increased understanding in three of fi ve
trials (one of which enrolled patients with cancer58).
All fi ve trials that assessed test or feedback strategies
showed improved understanding; however, these
studies have important drawbacks in their methods.
Flory and Emanuel57 suggest that improved person-to-
person interactions (ie, extended discussions and,
possibly, test or feedback) are the most eff ective strategy
to improve participant understanding. However, they
also conclude that further research is needed.
In summary, research suggests that modifi cation of
the content, writing style, format, or length of the
consent form is no more successful than other
approaches that aim to improve comprehension.57 Do
we therefore abandon eff orts to improve the consent
form? For several reasons, we think that attention must
continue to be paid to the language of the consent form.
In clinical trials, simplifi ed language appeals to patients
and is associated with decreased anxiety and increas ed
satisfaction. Knowledge of the usefulness and compre-
hension of the consent form from the pers pective of
others who might use it would be useful. For example,
parts of the con sent process might be administ ered
by health-care profes sionals other than the investigator,
or the patient might discuss the consent form with
their general practitioner. These professionals might
welcome simple explanations of the trial that are easy to
convey.
Knowledge of whether family members infl uence the
decision to participate; whether they rely on the consent
form to exert infl uence; and whether plain language is
more acceptable and comprehensible to them compared
with language used in standard forms would be useful.
To decide on the basis of the review by Flory and
Emanuel57 that plain language should be abandoned
and consent forms allowed to develop into even longer
and more complex documents would be a mistake. There
seems to be no reasonable argument for retaining the
highly technical language that is commonly found in
consent documents. The act of explaining has positive
eff ects apart from comprehensibility and, importantly,
“represents a tangible commitment to the informed-
consent process”.40
The discussion
Alongside written information comes the discussion
between a prospective trial participant and the
investigator, trial coordinator, research nurse, or research
assistant.
Although the patient’s signature might represent
agreement, it does not imply understanding. It might be
evidence of consent, but not proof. Given the duty of
disclosure and the patient’s individual circumstances,
researchers should record details of risks explained,
queries and concerns raised by patients, and responses
to these queries. An attempt to assess understanding
should be made and documentation recorded.
Various recommendations have been made on making
the information given brief, simple, and clear; on
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presenting risk information that might raise anxiety in a
non-threatening way; and on involving potential study
participants by asking them to answer multiple-choice
questions or writing about the information.59
Decision aids and prompts
A decision aid might improve satisfaction and under-
standing, at least for some studies and some patients.
A decision aid for women who were considering partici-
pation in prevention studies for breast cancer seems to
have been received favourably.60 After reading the deci-
sion aid, women seemed to have good subjective under-
standing of the clinical trial.
Currently under investigation in a randomised controlled
trial is the use of a question prompt sheet about clinical
trials. These sheets increase question-asking, and, when
endorsed by the doctor, decrease anxiety, shorten
consultations, and improve recall of information.61
Training of investigators
In 1997, Skene and Millwood,62 showed poor under-
standing by doctors of the law’s requirements for
disclosure, which might be improved with increased
education.62 The researchers suggest that medical
journals are an important way that doctors gain new
knowledge. Gore63 highlighted a hospital-based post-
graduate education programme on ethical issues
including informed consent. As discussed earlier, a
validated measure exists to assess the quality of informed
consent,34 which enables comparisons between diff erent
approaches.
Brown and co-workers64 have established a set of ethical
communication strategies based on ethical, linguistic and
psychological theory to assist doctors when discussing
possible trial participation. Moreover, they assessed the
eff ect of a 1-day communication skills training workshop,65
which seemed to have some modest eff ect.
Improvement of the consent process
Plain language aims to simplify explanations such that
the meaning is clear to a readership with varying reading
experience and abilities. A clear and simple message is
likely to be understood by more people than a message
with complex wording.
Plain language is important during the consent
discussion. The discussion allows for checking of
understanding—an important advantage over a form,
however simply it is written. Panel 2 is a checklist for
clear communication.
Suggestions for writing a consent form
Use of familiar words and ideas
Most trial sponsors and investigators tend to use technical
language. However, research participants might have
poor or incomplete understanding of medical or research
terms. Furthermore, some trial-related terms such as
“protocol”, “open-label”, and “subsequent” might be
understood poorly.66
If possible, terms that are likely to be familiar to people
without specialised health knowledge should be used.
Writing that includes familiar vocabulary and ideas is
easy to read and comprehend.67
Some ideas, even when worded simply, might be
inaccessible to some people, which might explain the
failure of strategies intended to improve readability and
therefore comprehension. For example, Bjorn and
colleagues50 highlight that older people had diffi culty
understanding “randomisation”, even when explained
simply. Consistent evidence of such diffi culties should
alert investigators to focus on these challenging areas
during discussions of informed consent.
Use of short words and sentences
Words of three or fewer syllables should be used when
possible; words of more than three syllables begin to
aff ect readability.40 However, health-care professionals are
unlikely to be able to (or want to) produce a consent
document written entirely in very short words and
sentences. Rather, consideration should be given to
improving readability through use of short, but equally
acceptable, words, and through breaking longer sentences
that contain several ideas into shorter sentences that
contain only one.
The paragraph below has several words of more than
three syllables and is assessed by the Flesch-Kincaid
readability checker as around grade level 15 (panel 3).
The fi rst sentence also contains several diff erent ideas:
“As with any experimental treatment, additional
unexpected and sometimes serious side eff ects, apart
from those listed here, are a possibility. If you have any
unusual symptoms, you should report them to your
medical practitioner immediately”.
A rewritten version below has shorter words (and is a
little longer because it includes an explanation of
“experimental”). It is assessed as grade level 5·2. We
have rewritten the sentences to decrease the ideas in
every one. We thought it important to stress to patients
to see their doctor about any health change, rather than
leaving it up to them to determine whether a symptom
is “unusual”:
Panel 2: Checklist for clear communication
• Use familiar words and ideas
• Use short words and sentences where possible
• Avoid misleading descriptions
• Use readability checkers or formulae to estimate reading
grade level (see panel 3)
• Discuss standard treatments and trial treatments
• Encourage support from others
• Give information to take away
• Check understanding
490
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“This treatment is experimental. This means it has not
been tested very much on people. We know about side
eff ects that can sometimes happen with this experimental
treatment. The known side eff ects are listed on this page.
But there could be side eff ects that we don’t yet know
about. Tell your doctor right away about any change in
your health”.
However, the meaning should not be compromised by
needless simplifi cation of long words to improve readability
score.68 In an example about chemotherapy below, there is
no need to replace “chemotherapy” in a plain-language
statement for an adult. It is a term that people who can
read adequately will come to recognise during treatment:
“The aim of chemotherapy is to kill cancer cells that may
have escaped treatment and still be in the body. These
cancer cells could cause the cancer to return”.
Note that some short words are diffi cult and unfamiliar,
such as “protocol”; arguably, so too is “research”. It is
important to try to use familiar words and check
understanding with the person during the consent
discussion.
Plain language is not the same as children’s writing
Most people appreciate that plain language and simple
materials do not off end people who are highly educated.31
The example below is from a book that explains breast
cancer to children.69 Children’s writing is characterised
by intensifi ers and repetition, and commonly has a story
form:
“‘Then why do you have to keep having the medicine?’,
Harriet asked. ‘Good question’, said Mum. ‘It’s to try to
make sure that every little bit of the cancer is gone.
Cancer can grow again from a very small bit. So small
that it’s hard to see. And we want to make sure that every
little bit has gone’”.69
The same information in plain language for an adult
would read like the chemotherapy example above. Unlike
children’s writing, plain-language writing for adults
permits some diffi cult words and the option to include a
glossary or explanation of diffi cult terms. It also assumes
some level of knowledge—eg, some understanding or
ability to grasp the idea of “cells”.
Use of bullet points to break-up long explanations
Even experienced readers can fi nd a long and dense
paragraph daunting. Note the following example:
“The eff ects of this treatment on the unborn child are
not known. If childbearing is a possibility, you will be
required to undergo a pregnancy test prior to
commencing the study. If you are male, you should not
father a child while participating in this study. Male
participants are strongly advised to use eff ective
contraception during the course of the study and for a
period of 12 months after the completion of the study.
Women of childbearing potential must agree to use a
reliable method of birth control for the duration of the
study and for a period of 12 months after the completion
of the study”.
This text can be summarised into bullet points:
“The eff ects of this treatment on the unborn child are
not known.
• You must not become pregnant or father a child
while in the study.
• Women who may become pregnant will be asked to
have a pregnancy test before joining the study.
• Men and women must use reliable contraception
while in the research study and for 12 months
afterwards”.
Avoidance of misleading descriptions
Potentially misleading descriptions need to be
anticipated and avoided. For example, use of “treatment”
rather than “experimental treatment” in phase I clinical
trials might reinforce misapprehension that the study is
aiming to treat rather than test toxic eff ects or establish
a maximum tolerable or a biologically eff ective dose. In
traditional dose-fi nding phase I studies, investigators
need to state clearly that the trial is experimental, and
should be clear that benefi t from the trial is unlikely.32
The table shows examples of other language to avoid.
Use of readability checkers or formulae to estimate
reading level
Advice on which reading level to aim for in patient
information ranges from about 4th grade to that of 9th
grade.15,43,66 Achievement of a low reading grade alone is
inadequate to ensure good understanding and compre-
hension.44 Moreover, a readability checker does not assess
sense (panel 3).
Suggestions for the consent discussion
Extended discussions between study staff and research
participants might improve patient understanding. Further
research is needed on the content of, and other matters
around, consent discussions.57 Aaronson and colleagues58
assessed patients with cancer who were considering
Panel 3: Establishment of document readability
Readability can be calculated through various formulae.
Microsoft Word (Microsoft Corporation, Washington, DC,
USA) can calculate readability according to two formulae:
Flesch reading ease and the Flesch–Kincaid grade level. In
versions of Word older than 2007, select “Tools”, followed by
“Options”, and “Spelling and Grammar”. Tick the box: “Show
readability statistics”. After running a check of spelling and
grammar, a box will indicate Flesch reading ease (score ranges
from 0 to 100, low numbers indicating harder-to-read text)
and the Flesch–Kincaid grade level. The grade level indicates
that the text might be understood by a typical student in that
US grade of schooling.
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participation in phase II or III studies. Patients received
standard consent discussions, with or without a subsequent
nurse telephone contact. Those who had the additional
telephone discussion were more informed about several
features of trial participation compared with those who did
not have the telephone discussion.
We recommend being mindful of most of the plain-
language features discussed above for written consent
documents. In addition, the discussion should also take
into account the following.
Discussion of standard treatments and trial treatments
Information about the trial should be presented clearly
and simply.59 The conversation should fi rst include a
discussion of standard treatments, followed by discussion
of potential treatment as part of a clinical trial.37,70
All matters relevant to a particular person must be
discussed, including procedures, risks, costs, time
implications, and their own understanding of personal
benefi t from the trial. People must understand that they
can withdraw from the trial at any time without
explanation and without compromising their medical
care. Verbal presentation of items normally included in
an informed-consent document and responses that are
refl ective, patient-centred, and supportive might be
associated with increased accrual to clinical trials.71
Encouragement of support from others
Involvement of people in the processing of information
is important.59 The patient should be encouraged to have
a friend or relative with them, and they might wish to
have an extra nurse or other professional attend the
interview with them.29,70,72
Provision of information to take away; encouragement
of time to consider
The patient should, according to their preference, be
given written information or a recording of the
conversation (or both).72 Delaying of consent might
increase satisfaction with participation and improve
understanding.14,29,70–73
Checking of understanding
Health-care professionals should check patients’
understanding. Patients should be asked whether they
have any questions and be off ered time to think about
the information and discuss with others.74 So-called teach
back can confi rm understanding.44,57 Health-care profes-
sionals ask the person to say in their own words what
has been described, and ask again if the patient’s words
show incomplete or inaccurate understanding.75 The
question, “Do you understand?” should not be asked;
people will generally answer, “yes”. Patients might think
that they have understood the information and might
report high levels of satisfaction, but have poor
understanding.14,29
Conclusion
“Making sure that patients are fully informed before
they agree to be included in any randomized clinical trial
has been, and continues to be, an immense challenge
for all who are concerned with the ethical advancement
of science”.76
Many studies have assessed the language of consent.
Recently, they have focused on the content and particularly
the language of the written-consent form. However,
conclusions such as those reached by Flory and Emanuel57
reinforce the importance of discussion between the
investigator or clinical-research professional and the
patient.
There are reasons for putting eff ort into the production
of plain-language participant information and consent
forms. However, evidence suggests that these forms
should not be relied on solely to ensure that a person
understands details about a trial. Plain-language forms
should be seen as part of the process that aims to achieve
meaningful informed consent.
Consent is a process, rather than an event, and
professionals and research participants should
continue to engage in conversation to ensure good
understanding, satisfaction, and continuing consent to
participate.
Original language Improved language
People are not tumours “You have progressed on…” “The cancer has grown…”
“You have failed chemotherapy” “The chemotherapy is no longer helping you”
Avoid language that might be inappropriately
persuasive or exploits vulnerability
“You have been invited…” “This trial might be suitable for you”
“If you are eligible...” “If the trial is suitable for you...”
“Because there are no other options…” “Instead of being in this study, you might decide to have…”
Address the reader as “you” and consider their
perspective
“Study participants will…” “If you choose...”
“Giving study medication intravenously and
collecting blood samples might involve
temporary discomfort or bruising”
“If you choose to join this trial, you will have the drugs
through a needle in your arm. The doctor will also use a
needle to take blood for testing. You might have a bit of
pain or bruising from the needle”
Table: Examples of language found in consent forms that could be improved
492
http://oncology.thelancet.com Vol 9 May 2008
Health-care Development
Confl icts of interest
The authors declared no confl icts of interest.
Acknowledgments
We thank Jeremy Kenner, Ethics Coordinator, Peter MacCallum Cancer
Centre, Victoria, Australia, for advice.
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