German Translation and Cross-Cultural Adaptation of the Limb Deformity-Scoliosis Research Society (LD-SRS) Questionnaire

Abstract

Background: Patient-reported outcome measures are gaining increasing importance in clinical research and quality control. Clinical impairment through limb deformities can appear in various forms. This study aimed at translating and culturally adaptating the Limb Deformity-Scoliosis Research Society (LD-SRS) patient-reported outcome measure (PROM) into German by following the scientific rigor of the cross-cultural adaptation process as well as ensuring the reliability of the translated version. The LD-SRS is applicable in children and adults. Methods: The translation was performed in accordance with the creators of the LD-SRS following the Professional Society for Health Economics and Outcomes Research (ISPOR) guidelines for translation and cultural adaptation. Two forward translations were performed, and after a consensus meeting, a professional translator translated the PROM back to English. The creators reviewed the back translation of the preliminary German version. Thirty patients with upper and lower limb deformities participated in cognitive debriefing interviews. The version was proofread and, finally, the test-retest reliability was estimated. Results: The mean age was 19 years (range 6–61). Twenty-six patients (87%) completed the retest after 6 days (range 3–26). The internal consistency was estimated with a Cronbach’s alpha of 0.96 (range 0.94–0.97), and the intraclass correlation was 0.92 (range 0.89–0.94), indicating an excellent reliability. The scores were normally distributed. Thereafter, the German version was proofread and finalized. Conclusions: The German translation and cross-cultural adaptation of the LD-SRS score resulted in a high reliability and internal consistency. The German LD-SRS score is readily usable and may be applied in future studies of German-speaking limb deformity patients.