 Until now, there is no validated German language screening questionnaire for symptoms of respiratory muscle weakness and SDB. Steier et al. published an English language questionnaire which was validated as a screening tool in 33 patients with very different neuromuscular disorders which were predominantly neurogenic Steier et al. 2011. In this study, SDB was defined by an apnea hypopnea index above 5 per hour. Nocturnal oxygen saturation and CO2 monitoring were not taken into account at all. In addition the questionnaire does not systematically cover sleep-related symptoms of SDB in detail such as sleep disruption and morning headache which have to be separated from daytime symptoms such as dyspnea or orthopnea, respectively. 