Bridging Disciplinary Boundaries (January 11 - 14, 2007)

Purpose: Research has consistently found that symptoms of posttraumatic stress disorder (PTSD) are prevalent among individuals exposed to various traumatic events, and PTSD is more prevalent than previously believed. We are just beginning to understand PTSD; it is an important disorder that is likely to be more prevalent, particularly in community samples, than has been recognized to date. The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) conceptualization of PTSD includes three symptom clusters: experiencing, avoidance/numbing, and arousal. The PTSD Checklist-Civilian Version (PCL-C) was designed to correspond to the DSM-IV PTSD symptoms. Two- and four-factor solutions have also been proposed, but empirical support has been limited. The purpose of this study was to examine different factor structures of PTSD in a particularly relevant population, women bringing their children to metal health treatment. Methods: Data were obtained from participants in studies 2 and 3 (N = 339). The PCL-C was administered as part of the assessment battery. Confirmatory Factor Analysis (CFA) was used to test two-, three-, and four- factor solutions. Each model was evaluated by visually inspecting several fit indices: the overall model chi-square (χ²), the root-mean-square error of approximation (RMSEA), and the comparative fit index (CFI). Additionally, chi-square difference tests were used to evaluate competing models. Results: Total PCL-C scores ranged from 17 – 85 with a mean score of 34.86 (SD=15.76). Nearly 19% of the women scored above the PCL-C cut of 50, suggesting probable PTSD. In addition, 23.3% of the women met the DSM-VI symptom cluster scoring method criteria for probable PTSD diagnosis. Our data did not confirm the DSM-IV PTSD symptom clusters. Although many of the models are comparable in some of their indices, the four factor solution was the best fit, χ² (113) = 190.36, p < .001, CFI = .965, RMSEA = .045. Four-factor solution includes four subscales: reexperincing, avoidance, numbing, and arousal factors. Implications: Empirical tests of the DSM-IV symptom clusters are important since the current diagnostic approach requires individuals to meet a minimum number of symptoms from each cluster. Our study suggests that several symptoms do not accurately reflect their DSM-IV assigned symptom cluster. This finding is consistent with previous research that suggests that separate subscales for avoidance and numbing might better reflect the construct of PTSD. This study adds to the existing knowledge base by giving professionals a better understanding of PTSDs underlying constructs, and aids in confirming the usefulness of the PCL-C as a screening tool.