The goal of this prospective observational study is to learn about the current prevalence of obstructive sleep apnea-hypopnea syndrome in community population, patients with specific diseases and special population from China. The main question it aims to answer is: (1) What are the prevalence and clinical characteristics of OSA in the community population, the specific disease population and the special population respectively? (2) How about the application value of each OSA screening questionnaire for different populations?Participants will all complete a screening questionnaire, and some will be selected by random sampling to complete either a polysomnography (PSG) or a portable sleep monitor (PM).