Dr. Diana Silver, associate professor of public health policy and management at New York University College of Global Public Health has just had her study, “The Impact of New York City’s Increased Minimum Legal Purchase Age on Youth Tobacco Use,” published in the American Journal of Public Health. The study uses both the Youth Risk Behavior Surveys (YRBS) and Youth Tobacco Survey (YTS) data in a rigorous difference-in-difference design with two comparison groups. It shows that although New York City (NYC) saw a modest decline in youth smoking following the passage of the new law, increasing the minimum legal purchase age (MLPA) to 21 years did not accelerate reductions in youth tobacco use any more rapidly than the declines observed in the comparison groups.
The large reductions in adolescent smoking over the past 20 years in the United States have been attributed to an aggressive and multipronged public health strategy. Still, in 2015, nearly one fifth of high-school students reported using a tobacco product in the past 30 days and use of e-cigarettes has continued to rise. The risks of such use are considerable, given tobacco’s deleterious effects on adolescent tissue and organ development and that early exposure is associated with higher risk of nicotine addiction. The purpose of this study was to assess the impact of these legal changes on adolescent tobacco use in New York City (NYC).
The authors performed a difference-in-differences analysis comparing NYC to the rest of New York State by using repeated cross-sections of the New York Youth Tobacco Survey (2008 – 2016) and to four Florida cities by using the Youth Risk Behavior Surveys (2007 – 2015). The results of their study show that adolescent tobacco use declined slightly in NYC after the policy change. However, this rate of change was even larger in control locations. In NYC, e-cigarette use increased and reported purchases of loose cigarettes remained unchanged, suggesting uneven policy implementation, enforcement, or compliance.
They concluded that increasing the MLPA to 21 years in NYC did not accelerate reductions in youth tobacco use any more rapidly than declines observed in comparison sites. Other cities and states currently raising their MLPA for tobacco may need to pay close attention to policy enforcement and conduct enhanced monitoring of retailer compliance to achieve the full benefits of the policy.