The structure of posttraumatic stress symptoms.
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.
Taylor
S
S
Department of Psychiatry, University of British Columbia, Vancouver, Canada. taylor@unixg.ubc.ca
Kuch
K
K
Koch
W J
WJ
Crockett
D J
DJ
Passey
G
G
D000328:Adult; D003130:Combat Disorders / Q000175:diagnosis / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D010555:Personality Inventory / Q000706:statistics & numerical data*; D011594:Psychometrics; D015203:Reproducibility of Results; D013313:Stress Disorders, Post-Traumatic / Q000145:classification / Q000175:diagnosis* / Q000523:psychology