Measuring statewide merchant compliance with tobacco minimum age laws: the Massachusetts experience.

OBJECTIVES: This study evaluated merchant compliance with laws prohibiting the sale of tobacco to minors in Massachusetts. METHODS: Stratified cluster sampling was used to select outlets from which youths aged 13 to 17 years attempted to purchase tobacco. RESULTS: Illegal sales were more common when the youth purchasing the tobacco was older, when the clerk was male, and when tobacco was obtained from a self-service display or unlocked vending machine. Failure to request proof of age was the strongest predictor of illegal sales. CONCLUSIONS: Measured compliance rates are strongly influenced by the age of the youths used to purchase tobacco.