Validation of a brief screen for Post-Traumatic Stress Disorder with substance use disorder patients.

To evaluate a 4-item screen for Post-Traumatic Stress Disorder (PTSD) for use with patients diagnosed with substance use disorders, 97 patients were recruited from substance use disorder treatment clinics at a large medical center. Participants completed the self-administered 4-item PTSD screen. Psychologists interviewed patients using the Clinician Administered PTSD Scale (CAPS). Sensitivity and specificity were calculated using the CAPS as the criterion for PTSD. Results were compared to chart diagnoses. The prevalence of PTSD was 33%. The screen identified 91% of PTSD cases, where only 25% of PTSD cases were diagnosed in the medical chart. The screen demonstrated good test-retest reliability (r=.80) and yielded a sensitivity of .91 and specificity of .80 using a cut score of 3. Likelihood ratios indicate that the screen has good ability to detect PTSD in this population, and that patients with positive screens that do not meet criteria for PTSD are likely to report significant subthreshold symptoms. Screening for PTSD in SUD treatment settings is time efficient and may increase the detection of previously unrecognized PTSD.