Trauma Mental Health Screening Language Concordance Between Provider and Patient and Post-Traumatic Stress Disorder Disclosure Accuracy Among Congolese Survivors: A Difference-in-Differences Analysis of Interpreter-Mediated Encounters

Language concordance between provider and patient is widely assumed to improve the accuracy of trauma mental health screening, but the assumption has not been tested against the specific disclosure dynamics that govern post-traumatic stress disorder (PTSD) reporting among forcibly displaced Congolese survivors. The framework treats disclosure as a signalling problem in which the perceived safety of the encounter, the precision of symptom translation, and the anticipated social consequences of disclosure jointly determine what a survivor reports. It specifies concordant direct-language encounters and interpreter-mediated encounters as the two exposure conditions, uses discordant encounters as the counterfactual, and derives the parallel-trends assumption required for identification. The analysis is methodological and conceptual: no primary data were collected, and the paper does not report empirical estimates. Instead it formalises the estimand, distinguishes disclosure accuracy from disclosure volume, identifies the mechanisms through which interpreter mediation could bias screening classification in either direction, and states the conditions under which the difference-in-differences design would recover a credible causal effect. The contribution is a testable specification of a widely invoked but poorly defined clinical assumption, together with an explicit account of the threats to its identification in Congolese displacement contexts.