A method for characterizing sleep disordered breathing may include identification of at least one of a plurality of predefined airway structural sources associated with a sleep disordered breathing event based on airflow data. In one example, an identification of at least one of a plurality of predefined airway structural sources associated with a sleep disordered breathing event is made based on data indicative of a ratio of a difference between a peak inspiratory airflow rate and a mid-inspiratory airflow rate to the peak inspiratory airflow rate captured during occurrence of the sleep disordered breathing event.