A parameter quantifying deviation from Gaussianity distribution of a patient's sounds, in the form of a non-Gaussianity distribution index, may be used to assist in diagnosis of sleep dysfunction such as OSAHS. A method for diagnosing a sleeping disorder of a subject includes processing a digitized audio signal from the subject with at least one electronic processor. The processing includes estimating a parameter quantifying deviation from Gaussianity distribution of the audio signal. in the form of a non-Gaussianity Index (NGI). The NGI value is then applied to a diagnostic model. The presence of a sleeping disorder is then indicated based on the output of the diagnostic model.