Testing predictions from the Memory and Identity Theory of ICD-11 Complex Posttraumatic Stress Disorder: Measurement development and initial findings

The 'Memory and Identity Theory' of ICD-11 Complex Posttraumatic Stress Disorder (CPTSD) was recently published but has not yet been subjected to empirical testing. The objective of this study was to evaluate newly developed measures of memory and identity disturbances and test hypothesized structural relations between these constructs and CPTSD symptoms. Self-report data were collected from a nationwide sample of adults living in Ukraine (N = 2,050) in September 2023. Exploratory factor analysis was used to assess the latent structure of the newly developed measures, and structural equation modeling was used to test the associations between memory and identity disturbances and CPTSD symptoms. 90% of participants experienced a lifetime trauma, and 9.2% screened positive for ICD-11 CPTSD. Results indicated that the newly developed measures of memory and identity problems possessed satisfactory psychometric properties, and all but one of the model-implied structural associations were observed. This study provides initial empirical support for the Memory and Identity theory of ICD-11 CPTSD, indicating that the basis of this disorder lies in distinct memory and identity processes. Several effects not predicted by the theory were observed, and these can provide the basis for further model testing and refinement.