Combining transdermal and breath alcohol assessments, real-time drink logs and retrospective self-reports to measure alcohol consumption and intoxication across a multi-day music festival

Introduction and Aims. Comprehensively investigating alcohol-related behaviours in the context of a dynamic multi-dayalcohol-licensed event is important for understanding and minimising patron risk. We aimed to assess the measurement utilityof implementing a multi-dimensional alcohol assessment battery using biometric data collection, real-time drink logs and retrospective self-report measures over the course of a 4-day music festival. Methods. Fourteen adults participated (n = 7 male,mean age 21.9 years). Breath and transdermal alcohol concentration (BrAC and TAC, respectively) were measured usingbreathalysers and transdermal alcohol bracelets. A real-time drink log was completed via smartphones on initiating eachdrink, and a retrospective questionnaire was administered up to twice daily throughout the event (6 timepoints total).Results. While almost all participants (92.9%) logged significantly fewer drinks in real-time than they retrospectivelyreported via the twice-daily questionnaires, logs provided important contextual information including the types of drinks consumed and drinking intensity. Compared to BrAC, TAC provided a better understanding of the time course of intoxication,indicating highest alcohol consumption outside of static BrAC assessment windows. However, BrAC provided a better assessment of present state: all participants were 0.00% BrAC at departure despite over two-fifths (42.9%) of the sample’s lastTAC reading exceeding 0.00%. Conclusions. As standalone assessments, each method possessed limitations. As a combinedbattery, they were successfully administered simultaneously, resulting in a more comprehensive overview of alcohol consumption/intoxication over the prolonged drinking session. However, the marked burden of simultaneous administration should beconsidered, and measures should be chosen judiciously based on research needs. [Norman T, Peacock A, Ferguson SG,Kuntsche E, Bruno R. Combining transdermal and breath alcohol assessments, real-time drink logs and retrospective self-reports to measure alcohol consumption and intoxication across a multi-day music festival