Described are various embodiments of an acoustic upper airway assessmentsystem andmethod, and sleep apnea assessment system and method relying thereon. In oneembodiment, a non-invasive method is described for assessing upper airwayanatomy in asubject while breathing. This method comprises receiving as input at ahardwareprocessor a digital signal representative of respiratory sounds generated bythe subjectwhile breathing； isolating digital respiratory sound segments from saiddigital signal；computationally extracting a designated spectral feature from each of saidsegments tocharacterize said respiratory sounds within each of said segments；automaticallyevaluating each said extracted spectral feature against a preset upper airwayanatomymetric associated with said designated spectral feature to characterize agiven upperairway anatomy measure in the subject while breathing； and outputting a sleepapneaseverity indication based on said characterized upper airway anatomy measure.
