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Effects of a Responsible Retailing Mystery Shop Intervention on Age Verification by Servers and Clerks in Alcohol Outlets: A Cluster Randomized Cross-Over Trial

NCJ Number
Drug and Alcohol Review Volume: 37 Issue: 6 Dated: 2018 Pages: 774-781
Date Published
8 pages

This paper describes a research study aimed at determining whether mystery shopper interventions can successfully increase the rate at which clerks and servers at alcohol establishments will perform ID checks to verify the age of clients.


The authors of this report sought to address the problem of clerks and servers at alcohol establishments often failing to verify age. They propose that using mystery shoppers to provide performance feedback is one approach to improving age verification rates, and note that few controlled studies have evaluated mystery shop interventions. To fill this information gap, the authors present this report on a cluster randomized cross-over trial of a mystery shop intervention in 16 communities in four U.S. states. The intervention comprised monthly mystery shop events, after which clerks and servers received immediate feedback to reinforce age verification. Fixed effects multi-level logistic regressions indicated that the intervention led to a two-fold increase in the odds of age verification, and, overall, ID-checking increased from an average of 80 percent pre-intervention to 94-96 percent by the end of the program. The authors conclude that mystery shop interventions can indeed increase age verification for alcohol purchases and may be an effective supplement to compliance checks and responsible beverage service programs. Publisher Abstract Provided

Date Published: January 1, 2018