Abstract: A portable smart device, comprising a sensor coupled to the device, the sensor configured to sense a physiological parameter of a user, and a processor configured to perform a breath training session to determine breathing loop gain in an awake state by instructing the user to breathe in a specified manner, receive physiological data from the sensor, the physiological data representing the sensed physiological parameter of the user, and determine a value of the loop gain based on the physiological data from the sensor.

Abstract: Systems and methods for diagnosing sleep disordered breathing in a user are disclosed. The systems include a sensor assembly configured to detect physiological data of a user while the user is asleep. The systems also include an electronic computing device configured to receive the detected data from the sensor assembly, analyze the detected data for at least one sleep disordered event of the user, determine, from the analyzed data and the at least one event, whether the at least one sleep disordered event is indicative of a sleep disordered breathing symptom, and diagnose the user with a sleep disordered breathing condition when the at least one sleep disordered event is determined to be indicative of a sleep disordered breathing symptom. The systems also include an output device configured to communicate the diagnosed sleep disordered breathing condition to the user.