[Non-motor Symptoms Questionnaire and Scale for Parkinson's disease. Cross-cultural adaptation into the German language].

Idiopathic Parkinson's disease (PD) is a multisytem degenerative disorder. In addition to motor symptoms such as akinesia, rigidity and tremor, various non-motor symptoms occur, which are still insufficiently diagnosed. Moreover, the frequently used scales and scores do not adequately detect these non-motor symptoms. The Non-motor Symptoms Questionnaire (NMSQuest) is an established self-completed patient questionnaire with 30 qualitative questions covering all important non-motor symptoms of PD. The Non-motor Symptoms Scale (NMSScale) is a grade rating scale for estimating the frequency and severity of non-motor symptoms in PD. Since there are only original English versions of both questionnaires available, self-translated versions were frequently used or the questionnaires were not used at all in native German patients. We used international guidelines for cross-cultural adaptation of questionnaires to provide standard versions of both non-motor symptoms questionnaires in the German language.