The structure of posttraumatic stress symptoms

J Abnorm Psychol. 1998 Feb;107(1):154-60. doi: 10.1037//0021-843x.107.1.154.


Posttraumatic stress disorder, as defined by the Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev. and 4th ed.; American Psychiatric Association, 1987, 1994, respectively), is characterized by 17 symptoms, descriptively clustered into 3 groups: (a) intrusions, (b) hyperarousal, and (c) avoidance and numbing. The present study sought to identify the basic dimensions (factors) that underlie these symptoms. Two samples were assessed: 103 victims of motor vehicle accidents and 419 United Nations peacekeepers deployed in Bosnia. A principal axis factor analysis was conducted for each sample. In each sample, 2 correlated factors were obtained, which were very similar across samples. Factor 1 was labeled Intrusions and Avoidance, and Factor 2 represented Hyperarousal and Numbing. These factors loaded on a single higher order factor. The higher order factor accounted for 13% to 38% of variance in symptom severity, and the lower order factors accounted for an additional 8% to 9% of variance. If the authors assume that each factor corresponds to a distinct mechanism (R. B. Cattell, 1978), then the results suggest that posttraumatic stress reactions arise from a general mechanism, with contributions from 2 specific mechanisms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Combat Disorders / diagnosis
  • Combat Disorders / psychology
  • Female
  • Humans
  • Male
  • Personality Inventory / statistics & numerical data*
  • Psychometrics
  • Reproducibility of Results
  • Stress Disorders, Post-Traumatic / classification
  • Stress Disorders, Post-Traumatic / diagnosis*
  • Stress Disorders, Post-Traumatic / psychology