Crossing cultural barriers: an initial cross-cultural validation of the Arabic compared to the German version of the Posttraumatic Stress Disorder Checklist for DSM-5 using multi-group confirmatory factor analysis

<b>Background:</b> Post-traumatic stress disorder (PTSD) is prevalent worldwide, yet its phenomenology and prevalence vary according to individual and contextual factors. Due to heightened exposure to (post-) conflict environments, many Arabic-speaking individuals are at high risk of PTSD. The PTSD Checklist for DSM-5 (PCL-5) is a widely used screening tool for PTSD symptoms, validated in several languages, including German and Arabic. However, despite its frequent cross-linguistic and cross-cultural use, a comprehensive cross-linguistic and cross-cultural validation of the PCL-5 Arabic version still remains outstanding.<b>Objective:</b> To ensure the cross-linguistic and cross-cultural comparability of the PCL-5 German and Arabic versions, this study examined the measurement invariance in a heterogeneous sample of German-speaking (<i>n</i> = 283) and Arabic-speaking individuals (<i>n</i> = 295).<b>Method:</b> Sociodemographic data and characteristics of stressful life events were assessed. Subsequently, we examined the internal consistency of the PCL-5 Arabic and German versions and broaden current investigations on structural validity as conducted via confirmatory factor analyses (CFA) by multi-group confirmatory factor analyses (MGCFA) across both language versions.<b>Results:</b> The present findings show that the Arabic-speaking subsample reported more man-made trauma, which was associated with higher PCL-5 sum scores compared to the German-speaking subsample. The PCL-5 showed excellent internal consistency (Cronbach's <i>α</i> = .96). CFA indicated good model fit for all models tested, favouring the Anhedonia and Hybrid models. While MGCFA confirmed configural, threshold, and metric invariance, the scalar invariance could not be established.<b>Conclusions:</b> The present study supports previous research indicating that the factorial structure of the PCL-5 is consistent across both language versions in the CFA. Nevertheless, our findings show a lack of scalar invariance in the MGCFA, which suggests potential bias in the cross-linguistic and cross-cultural comparability of the PCL-5 sum scores between the Arabic and the German versions. This highlights the need for context-, language-, and culture-sensitive diagnostics to ensure accurate PTSD assessments.