The Complex Trauma Inventory: A Self‐Report Measure of Posttraumatic Stress Disorder and Complex Posttraumatic Stress Disorder

The work group revising the criteria for trauma‐related disorders in the International Classification of Diseases (ICD‐11) made several changes. Specifically, they simplified the criteria for posttraumatic stress disorder (PTSD) and added a new trauma disorder called complex PTSD (CPTSD). These proposed changes to taxonomy require new instruments to assess these novel constructs. We developed a measure of PTSD and CPTSD (the Complex Trauma Inventory; CTI) according to the proposed domains, creating several items to assess each domain. We examined the factor structure of the CTI in two separate samples of diverse college students (n ₁ = 391; n ₂ = 391) who reported exposure to at least one traumatic event and at least occasional functional impairment. After reducing the original 50 items in the item pool to 20 items, confirmatory factor analyses supported two highly correlated second‐order factors—PTSD and disturbances in self‐organization (DSO)—with PTSD (i.e., reexperiencing, avoidance, sense of threat) and DSO (i.e., affect dysregulation, negative self‐concept, and disturbances in relationships), each loading on three of the six ICD‐11‐consistent first‐order factors, root mean square error of approximation (RMSEA) = .056, 95% confidence interval (CI) .048, .064], comparative fit index (CFI) = .956, Tucker‐Lewis index (TLI) = .948, standardized root mean square residual (SRMR) = .043, Bayesian information criterion (BIC) = 641.55, χ²(163) = 361.02, p < .001. Internal consistencies for PTSD and DSO were good to excellent (Cronbach's αs = .89 to .92). Supplementary analyses supported the gender invariance of the CFA model, as well as convergent and discriminant validity of the CTI. The validity of the CTI supports the distinction between CPTSD and PTSD. Moreover, the CTI will assist clinicians with diagnosis, symptom tracking, treatment planning, and assessing outcomes.