Symptom validity indices in the Posttraumatic Stress Disorder Checklist for DSM‐5

Abstract

AbstractThe use of symptom validity tests (SVTs) is standard practice in psychodiagnostic assessments. Embedded measures are indices within self‐report measures. To date, no embedded SVTs have been identified in the Posttraumatic Stress Disorder Checklist for DSM‐5 (PCL‐5). This research aimed to develop and validate PCL‐5 SVTs in two samples of veterans. Participants completed one of two prospective research studies that included cognitive and psychological tests. Participants in Study 1 were veterans (N = 464) who served following the September 11, 2001, terrorist attacks; participants in Study 2 were veterans or service members (N = 338) who had been deployed to Iraq and/or Afghanistan. Both studies included the PCL‐5 and the Structured Inventory of Malingered Symptomatology (SIMS), the latter of which served as the criterion for identifying PCL‐5 SVTs. For Study 1, two separate SVTs were developed: the PCL‐5 Symptom Severity scale (PSS), based on the PCL‐5 total score, and the PCL‐5 Rare Items scale (PRI), based on PCL‐5 items infrequently endorsed at the highest item ratings. At the most conservative SIMS cutoff score, the PSS achieved excellent discrimination for both the Study 1, AUC = .840, and Study 2 samples, AUC = .858, with specific cutoff scores of ≥ 51 and ≥ 56 maximizing sensitivity while maintaining a specificity of .90. The PRI achieved good discrimination, AUCs = .760 and.726, respectively, with a cutoff score of 2 or higher indicated by both studies. The results of these two studies provide provisional support for these two embedded SVTs in the PCL‐5.