Translation, Linguistic Validation, and Reliability of the CLEFT-Q in a German Context

The aim of this study was to translate and culturally adapt the CLEFT-Q questionnaire into German and evaluate its reliability as an instrument for Patient Reported Outcome Measures (PROMs). The translation followed the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) guidelines. Applicability was tested through cognitive debriefings with 7 patients. Adjustments were made during the process to achieve a conceptually equivalent translation. Reliability was assessed by conducting retest interviews with 50 patients at 4-week intervals. Translation challenges included difficulties in 8.4% of items during forward translation, 31.1% of items when comparing the 2 forward translations, and 10.1% of items during back-translation review. Cognitive debriefings revealed comprehension issues with 4 items (3.4%). Internal consistency and stability were evaluated using Cronbach alpha and the intraclass correlation coefficient, both yielding values of 0.909, considered excellent. PROMs play a growing role in quality assurance for medical care. The CLEFT-Q is currently the only international tool specifically available for cleft lip and palate patients. Its German translation provides a reliable and valid instrument to assess outcomes in German-speaking regions, covering key aspects of patient experience, including satisfaction, functional outcomes, and health-related quality of life.