Evaluation of the German Version of the Keratoconus Outcomes Research Questionnaire
Purpose: To translate, validate, and evaluate the psychometric properties of the German version of Keratoconus Outcomes Research Questionnaire (KORQ). Methods: This prospective study included 3 phases. In phase 1, the KORQ was translated in a standardized way; in phase 2, Rasch validation was performed; in phase 3, the validated questionnaire was evaluated in a separate patient cohort. All patient