Validity and reliability of the Nijmegen Cochlear Implant Questionnaire in German

Background The Nijmegen Cochlear Implant Questionnaire (NCIQ) is a disease-specific questionnaire to determine the health-related quality of life (HRQoL) of patients before and after cochlear implantation. Objective This study aimed to assess the validity and reliability of the German translation of the NCIQ. Materials and methods A prospective study was performed in 100 postlingually deaf or severely hearing-impaired patients. HRQoL was assessed using the NCIQ, the Abbreviated Profile of Hearing Aid Benefit (APHAB), and the Hearing Participation Scale (HPS) before as well as 3 and 6 months after cochlear implantation. An untreated group of postlingually deaf or severely hearing-impaired patients (n = 54) served as a control. Cronbach's alpha and test-retest reliability were measured. The content, discrimination, and agreement validity were tested. The evaluation of construct validity was based on recently published data. Sensitivity and receiver operating curve (ROC) analysis, including consideration of the area under the curve (AUC), were used as quality criteria. Results The test-retest analysis showed stable NCIQ values 3 and 6 months postoperatively. The Cronbach's alpha values indicated good internal consistency. The NCIQ validly discriminated between treated and untreated patient groups. There were statistically significant albeit weak correlations between the NCIQ and the APHAB (r = -0.22; p = 0.04) and the HPS (r = 0.30; p = 0.01). Sensitivity and ROC analyses showed good measurement quality of the German-speaking NCIQ. Conclusion The German translation of the NCIQ reliably and validly measures HRQoL before and after cochlear implantation and can be used for clinical monitoring after treatment with cochlear implants.