[Diagnostics of posttraumatic stress disorder according to DSM-5 and ICD-11]

The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) and the International Statistical Classification of Diseases and Related Health Problems (ICD-11, Version 2018) differ with respect to the diagnostic criteria of posttraumatic stress disorder (PTSD). The present study investigated the implications of these differences for the classification of PTSD within a sample of German survivors of various traumatic events.

A total of 341 trauma survivors who participated in a multicenter study were classified according to DSM-5 and ICD-11 and the results were compared. The PTSD checklist for DSM-5 (PCL-5) was used to diagnose PTSD. The ICD-11 PTSD cases were identified using a "restrictive" and a "wide" operationalization of re-experiencing symptoms (i. e. with and without intrusive memories). Depression and the level of trauma-related impairment were also assessed.

The diagnosis rate using ICD-11 was significantly lower than under DSM-5 (DSM-5 64.5%, ICD-11 54.0%, p < 0.001) using a restrictive operationalization of re-experiencing symptoms but differences disappeared when using a wide operationalization. Rates of comorbidity with depression were reduced under ICD-11. Individuals with high and low levels of trauma-related impairment were equally likely to receive a PTSD diagnosis under ICD-11.

Differences in the diagnosis rates between ICD-11 and DSM-5 depend on the operationalization of the specific ICD-11 re-experiencing requirements. Precise diagnostic guidelines are necessary to avoid inconsistent diagnoses.