Posttraumatic stress disorder instrument wording content is associated with differences in factor structure

The authors examined posttraumatic stress disorder (PTSD) item wording differences on the factor structure of PTSD. Nonclinical, trauma-exposed participants were randomly assigned to complete a PTSD measure using item wording content from the PTSD Checklist (n = 182) or PTSD Symptom Scale (n = 203). Compared to the 4-factor emotional numbing PTSD model, the 4-factor dysphoria PTSD model fit best across groups based on smaller Bayesian information criterion (BIC) values. For PTSD Checklist participants, the numbing model's BIC was 6238.54 compared to the dysphoria model's BIC of 6156.03. For the PTSD Symptom Scale, the numbing model's BIC was 6161.38 compared to the dysphoria model's BIC of 6102.87. Groups differed on variable intercepts and residual variances. Instrument and construct implications are discussed.