Abstract: Interactive software applications designed to assess a combination of behavioral neuro-physiological characteristics of a user to determine an effect a substance is currently having on the user. In some examples the effect of the substance may be assessed to identify a cognitive impairment caused by a substance and determine the type of substance(s) likely causing the impairment. In some examples the effect of the substance may be assessed to determine a recommended dosage and/or a standard impairing dose threshold for a particular substance.