Interpreter-mediated psychotherapy with trauma-affected refugees - A retrospective cohort study.

The aim of this retrospective cohort study was to examine if interpreter-mediated psychotherapy with trauma-affected refugees affects treatment outcome. The clinical sample consisted of 825 patients who, as part of treatment, were offered 16 sessions of cognitive behavioural therapy. The cohort was allocated to two subsamples based on whether interpreters were used in psychotherapy or not and the treatment outcome for the two subsamples was compared. The primary outcome measure was severity of PTSD-symptoms (Harvard Trauma Questionnaire (HTQ)) and secondary outcome measures were depression and anxiety symptoms (Hopkins Symptom Checklist-25 (HSCL-25), Hamilton Depression and Anxiety rating scales (HAM-D, HAM-A)), somatisation (somatisation items of SCL-90 (SI-SCL-90)), quality of life (WHO-5-Well-being Index (WHO-5)) and functioning (Sheehan Disability Scale (SDS), Global Assessment of Functioning (GAF-F, GAF-S)). Compared to no use of interpreter, the use of interpreter in psychotherapy was associated with less improvement during treatment on the primary outcome measure HTQ and the secondary outcome measures HSCL-25, SI-SCL-90, SDS, WHO-5, HAM-A, but not on GAF-S, GAF-F and HAM-D. Based on the primary outcome measure HTQ and the majority of the secondary ratings the subsample in interpreter-mediated psychotherapy had less improvement in their mental health status compared to the subsample without interpreter.