Kimerling RE (VA Palo Alto HCS)
Trafton JA (VA Palo Alto HCS)
The PC-PTSD screen is a brief, self-administered screen for PTSD developed and validated for use in VA primary care settings. Identifying PTSD is especially important in patients with substance use disorder (SUD), as untreated PTSD is associated with relapse to substance use following SUD treatment. In this study we determine the reliability and validity of the PC-PTSD screen for the detection of PTSD among veterans in treatment for SUD.
Patients in SUD treatment at the VA Palo Alto Health Care System self-administer the 4-item PC-PTSD screen and are evaluated for PTSD using the “gold-standard” Clinician Administered PTSD Scale (CAPS) administered by trained interviewers blind to screen results. Chart diagnoses of PTSD are reviewed and compared to screen results to test whether the screen improves identification of SUD patients with PTSD. Patients complete a second self-administration of the PC-PTSD screen an average of 3 days following the research interview to assess reliability.
Preliminary results were calculated for the first 39 participants. A total of 18 patients (46%) were diagnosed with PTSD based on the CAPS. Spearman correlation indicates test-retest reliability of the screen is .87. ROC analyses comparing the screen to CAPS diagnoses indicate an optimal cut score of 3 positive responses (out of 4) on the PC-PTSD screen, with sensitivity of .83, specificity of .86, and efficiency of .84. At this cut score the screen reached 85% agreement with CAPS scores (kappa = .70), and detected significantly more patients with PTSD than were identified in chart diagnoses.
The 4-item PTSD screen is a time-efficient, reliable, and valid method to detect PTSD among SUD patients. The screen identifies previously undetected cases of PTSD among veterans in SUD treatment.
Approximately 30% of all VA SUD patients have co-morbid PTSD. Treating this PTSD is one of the most significant factors predicting the long-term remission from SUD for these patients. Few treatment facilities have the resources to conduct routine clinical evaluations for PTSD, and comorbid PTSD is often undetected and untreated. A brief, self-administered screen makes routine screening for PTSD among SUD patients feasible, and would promote better treatment outcomes for these comorbid patients.