Adaptation of the Cochlear Implant Quality of Life-35 Profile Into German

Purpose: The adaptation of existing questionnaires is a valuable method to make instruments available in multiple languages. It is necessary to assure the quality of an adaptation by following adaptation guidelines. The Cochlear Implant Quality of Life-35 Profile (CIQOL-35 Profile) was developed and validated to measure the functional abilities in English-speaking adult CI users but is not yet available in German. In this study, we performed a cross -cultural adaptation of this instrument to make it applicable in research and rehabilitation with German-speaking patients. Method: This study followed established practice guidelines for translating and adapting hearing-related questionnaires. Professional translators and health care professionals with experience with patients with hearing loss translated all items forward and backward multiple times. A committee reviewed the process and decided when a satisfactory consensus was achieved. Next, we examined the intelligibility of the German version using cognitive interviews with 15 adult CI users. Results: For most items, there was no difficulty with direct translation. In items that turned out to be more difficult to translate, it proved to be very helpful to compare the back translation to the original version, discuss the wording in the committee, and ask the source -language questionnaire developer. During the interviews, issues of comprehension for some phrases were identified. These phrases were changed according to the participant's questions and suggestions. Conclusions: The CIQOL-35 Profile was successfully adapted into German. The German version of the questionnaire is now available for research and clinical practice. Further validation of the German CIQOL-35 Profile is in progress.