A psychometric evaluation of the International Trauma Questionnaire (ITQ) in a trauma-exposed college sample

Introduction: The International Trauma Questionnaire (ITQ) is a well-validated measure of ICD-11 PTSD and CPTSD. However, further validation is needed in other samples and using external correlates representing a broader range of psychopathology.Objective: We first examined the internal consistency of the ITQ, and then examined its convergent and dis-criminant validity with a wide variety of external correlates, including PTSD, childhood trauma, dissociation, somatization, anxiety, anxiety related disorders, depression, mania, paranoia, schizophrenia, borderline fea-tures, antisocial features, drug use, alcohol use, aggression, suicidal ideation, stress, interpersonal function-ing, and treatment rejection.Method: Using data from a trauma-exposed sample of college students (N = 246), we evaluated internal con-sistency via Cronbach's alpha and MacDonalad's omega, and convergent and discriminant validity via Pear-son correlations and follow-up z tests using the Meng-Rosenthal-Rubin (1992) procedure to assess differences between the PTSD and DSO scales of the ITQ.Results: The ITQ has strong internal consistency reliability as indicated by Cronbach's alpha and Mac-Donald's omega. Patterns of convergent and discriminant validity fell broadly in hypothesized pat-terns, supporting the distinction between ICD-11 PTSD and CPTSD. All significant contrast analyses showed that correlations with external criterion variables were greater for ITQ DSO as compared to ITQ PTSD.Conclusions: Our results indicate that the ITQ is a psychometrically sound measure of ICD-11 PTSD and CPTSD. As indicated by the differential pattern in convergent and discriminant validity with a broad range of exter-nal correlates, the scale readily distinguishes PTSD and DSO as distinct constructs.(c) 2022 Elsevier Masson SAS. All rights reserved.