A system and methods for screening patients suspected of obstructive sleep apnea. The system includes a sound detection device configured for detecting tracheal respiratory sound signals of a patient and a Sao2 detection device for detecting SaO2 signals of the patient. The system also has a head position detection device for detecting the head positions of the patient during testing, and a processing module for receiving and analyzing the tracheal respiratory sound signals to extract sound data and the Sao2 signals to extract blood oxygen saturation data. The processing module further receives and analyzes the head position signals captured by the head position detection device to generate head position data. The system may further include a display for displaying information about the various data generated by the processing module.
