Reliability and validity of a brief instrument for assessing post-traumatic stress disorder

This study examines the psychometric properties of two versions of the PTSD Sympton Scale (PSS). The scale contains 17 items that diagnose PTSD according to DSM-III-R criteria and assess the severity of PTSD symptoms. An interview and self-report version of the PSS were administered to a sample of 118 recent rape and non-sexual assault victims. The results indicate that both versions of the PSS have satisfactory internal consistency, high test-retest reliability, and good concurrent validity. The interview version yielded high interrater agreement when administred separately by two interviewers and excellent convergent validity with the SCID. When used to diagnose PTSD, the self-report version of the PSS was somewhat more conservative than the interview version.