ArticlePublisher preview available

The modular structure of posttraumatic stress disorder in adolescents

January 2022
Current Psychology 42(1):1-13

January 2022
42(1):1-13

DOI:10.1007/s12144-021-02538-1

Authors:

Filipa Ferreira

University Institute of Maia

Daniel Castro

Instituto Superior da Maia

Tiago Bento

Instituto Superior da Maia

The nosographic structure of the symptoms of posttraumatic stress disorder (PTSD) remains unclear and this extends to younger age groups. Previous research has shown that adolescents express symptoms of PTSD differently in comparison with adults, highlighting potential differences and particularities of the nosographic structure of PTSD across different developmental stages. The network perspective of mental disorders is a promising approach to clarify the structure of PTSD. This study aims to identify the hierarchical modular structure of the network of PTSD symptoms in adolescents and the role of the different symptoms in that network. A sample collected in a previous study (Guo et al., 2015) of 662 adolescents (Mage = 13.05, SDage = 0.83) exposed to a pipeline explosion was reanalyzed. The PTSD Checklist-Civilian Version (PCL-C) was used to assess symptoms of PTSD. The network of symptoms was estimated with a non-regularized method, and the characterization of the modular structure and the role of symptoms in that network was performed using the ModuLand algorithm. A structure of two levels was found with a first level with 17 symptoms and five high-order modules. The module encompassing the reexperiencing symptoms showed the highest centrality values. Symptoms transversal to various disorders have high values of overlap between modules. Our findings suggest that a modular structure encompassing five modules captures the best representation of the PTSD structure in adolescents.

Hierarchical modular structure of the PTSD network. The symptoms in the network are represented by nodes (circles) of different colors and the edges (lines) connecting them depict their connections. The width of the edge represents the strength of the connection. The color of the nodes represents the module to which they most belong and the colors in the outer ring of the node display the amount of connection to other modules. The grey in the outer ring represents the absence of overlap. Light rose represents module 1; green nodes represent module 2; light green represents module 3; rose nodes represent module 4; and yellow nodes represent module 5. After the module number, in parentheses, is the name of the factor of the Dysphoric Arousal Model most similar to the estimated modules

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Measures of strength, modular bridgeness, and modular overlap of the PTSD symptoms in the first level

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Measures of effective degree and community centrality of the modules in the second level

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Current Psychology (2023) 42:13252–13264

https://doi.org/10.1007/s12144-021-02538-1

1 3

The modular structure ofposttraumatic stress disorder inadolescents

FilipaFerreira1,2 · DanielCastro1,2· TiagoBentoFerreira1,2

Accepted: 15 November 2021 / Published online: 13 January 2022

Abstract

The nosographic structure of the symptoms of posttraumatic stress disorder (PTSD) remains unclear and this extends to

younger age groups. Previous research has shown that adolescents express symptoms of PTSD diﬀerently in comparison

with adults, highlighting potential diﬀerences and particularities of the nosographic structure of PTSD across diﬀerent

developmental stages. The network perspective of mental disorders is a promising approach to clarify the structure of PTSD.

This study aims to identify the hierarchical modular structure of the network of PTSD symptoms in adolescents and the

role of the diﬀerent symptoms in that network. A sample collected in a previous study (Guo etal., 2015) of 662 adolescents

(Mage = 13.05, SDage = 0.83) exposed to a pipeline explosion was reanalyzed. The PTSD Checklist-Civilian Version (PCL-

C) was used to assess symptoms of PTSD. The network of symptoms was estimated with a non-regularized method, and

the characterization of the modular structure and the role of symptoms in that network was performed using the ModuLand

algorithm. A structure of two levels was found with a ﬁrst level with 17 symptoms and ﬁve high-order modules. The module

encompassing the reexperiencing symptoms showed the highest centrality values. Symptoms transversal to various disorders

have high values of overlap between modules. Our ﬁndings suggest that a modular structure encompassing ﬁve modules

captures the best representation of the PTSD structure in adolescents.

Keywords Posttraumatic stress disorder· Adolescents· ModuLand· Non-regularized method

Introduction

Over the years, the nosographic structure of the symptoms of

posttraumatic stress disorder (PTSD) has remained elusive

(Lee etal., 2019), and this uncertainty about its organiza-

tion extends to younger age groups (Russell etal., 2017).

Since its introduction in the third version of the Diagnos-

tic and Statistical Manual of Mental Disorders (DSM-III;

American Psychiatric Association, 1980) and its subsequent

revisions (Bartels etal., 2019), considerable disagreement

has emerged about the conceptualization (McNally, 2012),

number (Cao etal., 2017), and organization (Russell etal.,

2017) of PTSD symptoms. These divergencies have had a

signiﬁcant impact on the clariﬁcation of the nosographic

structure of PTSD (Bryant, 2019), which have resulted in

diﬀerent prevalence rates (North etal., 2016), an increase

in potential incorrect diagnosis (Elhai etal., 2012), and poor

assessment and treatment outcomes (Armour etal., 2016). In

addition, the structure of PTSD has been examined mostly

through factor analysis methods (Marshall etal., 2013),

which have revealed diﬀerent factor structures (Armour

etal., 2013), ranging between one and seven factors (Armour

etal., 2016; TableS1 in Supplementary Materials). This

way, a clear view of the symptomatic organization of PTSD

might help improve the diagnosis as well as the develop-

ment of more precise assessment instruments, treatment

techniques, and intervention plans (Armour etal., 2016).

In children and adolescents exposed to traumatic and

stressful events, research has only recently begun to address

the nosography of PTSD symptoms (Saul etal., 2008) and

their impact on development and functioning in later stages

of life (Kolaitis, 2017). To a signiﬁcant extent, this has been

achieved through studies based on factor analysis; however,

contradictory results have been found (Cao etal., 2017).

For example, Ayer and colleagues (2011a) performed a

All the authors wrote and performed the analysis of the manuscript

* Filipa Ferreira

ﬁlipaf@ismai.pt

1 Social Sciences Department, University ofMaia, Avenida

Carlos Oliveira Campos – Castêlo da Maia, 4475-690Maia,

Portugal

2 Center forPsychology atUniversity ofPorto, Porto, Portugal

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