Background: Unrecognized posttraumatic stress disorder (PTSD) is common and may be an important factor in treatment-resistant depression. Brief screens for PTSD have not been evaluated for patients with depression.
Objective: The objective was to evaluate a 4-item screen for PTSD in patients with depression.
Design: Baseline data from a depression study were used to evaluate sensitivity, specificity, and likelihood ratios (LRs) using the PTSD checklist (PCL-17) as the reference standard.
Subjects: Subjects are 398 depressed patients seen in Veterans Affairs (VA) primary care clinics.
Measures: The Patient Health Questionnaire (PHQ) for depression, PCL-17, and 4-item screen for PTSD were used.
Results: Patients had a mean PHQ score of 14.8 (SD 3.7). Using a conservative PCL-17 cut point "(>50)", the prevalence of PTSD was 37%. PCL-17 scores were strongly associated with PHQ scores (r = 0.59, P < 0.001). Among the 342 (86%) patients endorsing trauma, a score of 0 on the remaining 3 symptom items had a LR = 0.21, score of 1 a LR = .62, score of 2 a LR = 1.36, and score of 3 a LR = 4.38.
Conclusions: Most depressed VA primary care patients report a history of trauma, and one third may have comorbid PTSD. Our 4-item screen has useful LRs for scores of 0 and 3. Modifying item rating options may improve screening characteristics.