Estimating the quantity and time course of alcohol consumption from transdermal alcohol sensor data: A combined laboratory-ambulatory study.

Transdermal alcohol sensors offer enormous promise for the continuous, objective assessment of alcohol use. Although these sensors have been employed as abstinence monitors for some time now, it is only recently that models have been developed aimed at allowing researchers to derive estimates of the precise amount and time course of drinking, directly from transdermal data. Using data from a combined laboratory-ambulatory study, the current research aims to examine the validity of recently developed methods for estimating BrAC (breath alcohol concentration) directly from transdermal data. Forty-eight heavy social drinkers engaged in 7 days of ambulatory assessment outside the laboratory, and also participated in a laboratory alcohol-administration session. Participants wore the SCRAM transdermal sensor throughout the study, and during the 7 days of ambulatory assessment, they provided daily self-reports of their drinking and also took randomly prompted photographs 6 times per day, which were then evaluated for evidence of alcohol consumption. Results indicated strong associations between daily self-reports of drinking quantity and estimates of BrAC derived from transdermal sensors at both the between- and within-subject level. Data from randomly prompted photos indicated that the time course of estimated BrAC also had validity. Results offer promise for novel methods of estimating BrAC from transdermal data, including those taking a nomothetic (population-based) approach to this estimation, thus potentially adding to our arsenal of techniques for understanding, diagnosing, and ultimately treating alcohol use disorder.