Methods and systems for classifying a subject's cognitive state are provided. The method receives and stores sensor signals comprising a first sensor signal (SS_1) from a first sensor configured to sense a first aspect of the subject, and a second sensor signal (SS_2) from a second sensor configured to sense a second aspect of the subject. The validity of SS_1 and SS_2 are determined using a binary signal validity methodology and a weighted signal validity methodology. SS_1 and SS_2 are analyzed to identify patterns therein, and the patterns are defined as either an objective marker or a subjective marker. A subject profile is referenced and updated through multiple iterations. The subject's cognitive state is subsequently classified based on both adjusted subjective and objective markers.
