The structure of post-traumatic stress disorder symptoms in three female trauma samples: A comparison of interview and self-report measures

Abstract

Empirical research increasingly suggests that post-traumatic stress disorder (PTSD) is comprised of four factors: re-experiencing, avoidance, numbing, and hyperarousal. Nonetheless, there remains some inconsistency in the findings of factor analyses that form the bulk of this empirical literature.One source of such inconsistency may be assessment measure idiosyncrasies. To examine this issue, we conducted confirmatory factor analyses of interview and self-report data across three trauma samples. Analyses of the interview data indicated a good fit for a four-factor model across all samples; analyses of the self-report data indicated an adequate fit in two of three samples. Overall, findings suggest that measure idiosyncrasies may account for some of the inconsistency in previous factor analyses of PTSD symptoms. KeywordsFactor structure; Measurement; Post-traumatic stress disorder; Psychological assessment; Test validity; Trauma Both the revised third edition and the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-III-R, DSM-IV; American Psychiatric and Association, 1987, 1994) classify post-traumatic stress disorder (PTSD) as an anxiety disorder that develops in response to a perceived traumatic event. The diagnosis of PTSD is further characterized by three distinct symptom clusters: (1) re-experiencing of the traumatic event through such phenomena as dreams, flashbacks, and intrusive, distressing thoughts; (2) avoidance and © 2007 Elsevier Ltd. All rights reserved. * Corresponding author. Tel.: +1 714 278 8428; fax: +1 714 278 7134. cscher@fullerton.edu (C.D. Scher).. Publisher's Disclaimer: This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. (Foa, Zinbarg, & Rothbaum, 1992), and may bear different functional relationships with interpersonal functioning, with physical health, and with symptoms often found co-morbid with post-traumatic stress symptoms (Kimerling, Clum, & Wolfe, 2000;Ruscio, Weathers, King, & King, 2002;Stewart, Conrod, Pihl, & Dongier, 1999;Stewart, Pihl, Conrod, & Dongier, 1998). Thus, a clear understanding of the nature of PTSD symptom clusters has the potential to inform both knowledge of how various PTSD symptoms develop and how these symptoms relate to co-occurring difficulties.Nonetheless, since the advent of DSM-III-R, the adequacy of these clusters for describing PTSD has been questioned. Much of this questioning derives from the findings of factor analyses that have consistently reported between two and four factors, and which have not supported the three-factor, hierarchical structure of PTSD symptoms outlined in the DS...

Measuring posttraumatic stress following childbirth: a critical evaluation of instruments

“…Previous studies have also challenged the threedimensional structure of the DSM-IV symptoms. Occasionally, two underlying factors (intrusions/ avoidance, hyperarousal/numbing) [28,29] were found, whereas others reported four underlying factors [30][31][32][33]. The present findings suggest that PTSD includes a cluster of symptoms shared with other diagnoses (dysphoria) as well as a more specific factor related directly to the effects of encountering traumatic experience is in line with current research on this topic [34].…”

A multi-sample confirmatory factor analysis of PTSD symptoms: What exactly is wrong with the DSM-IV structure?

“…Two of the 34 matrices were ultimately excluded as ineligible. Of the remaining 32 studies, three were omitted to address non-independent data stemming from administration of multiple PTSD measures to a single sample (i.e., Palmieri et al, 2007b; Scher, McCreary, Asmundson, & Resick, 2008) or to analyses conducted using non-independent samples (i.e., Simms et al, 2002). 4 In all, the analytic sample consisted of 29 data sets.…”

“… 4 In their sample of recent survivors of sexual assault ( N = 216), Scher et al (2008) analyzed PTSD symptom severity information obtained using the Clinician-Administered PTSD Scale (CAPS; Blake et al, 1995) and the PTSD Symptom Scale (PSS; Foa, Riggs, Dancu, & Rothbaum, 1993). Similarly, Palmieri et al (2007b) presented data from both the CAPS and the PTSD Symptom Checklist (PCL; Weathers et al, 1993) collected from a single sample of utility personnel who had worked at the World Trade Center in the aftermath of the 9/11 terrorist attacks.…”

The factor structure of posttraumatic stress disorder: A literature update, critique of methodology, and agenda for future research

“…The emotional numbing model (King et al, 1998) is distinct from DSM-IV's three-factor PTSD model in that avoidance was divided into two factors -effortful avoidance and emotional numbingcorroborated by these factors' differential prediction of treatment response, and associations with treatment outcomes and psychopathology (reviewed in Asmundson et al, 2004). Most recently, this model has been supported in adult trauma-exposed samples of the general population (Cox, Mota, Clara, & Asmundson, 2008;Elhai, Grubaugh, Kashdan, & Frueh, 2008;Grubaugh, Long, Elhai, Frueh, & Magruder, 2010), military veterans (Elhai, Palmieri, Biehn, Frueh, & Magruder, 2010;Mansfield, Williams, Hourani, & Babeu, 2010;McDonald et al, 2008), medical patients (Naifeh, Elhai, Kashdan, & Grubaugh, 2008), crime victims (Scher, McCreary, Asmundson, & Resick, 2008), refugees (Palmieri, Marshall, & Schell, 2007), disaster workers (Palmieri, Weathers, Difede, & King, 2007), elderly (Schinka, Brown, Borenstein, & Mortimer, 2007), college students (Elhai, Gray, Docherty, Kashdan, & Kose, 2007;Hoyt & Yeater, 2010), and adolescents (Kassam-Adams, Marsac, & Cirilli, 2010;Saul, Grant, & Carter, 2008). …”