摘要：We used a longitudinal design to investigate the impact of a government policy banning the display of tobacco products at the point of sale. The extent of tobacco promotions in 481 randomly selected stores was documented at 4 points in time (2005–2009). Tobacco promotions were greatly reduced after implementation of the display ban. A ban on the display of tobacco products and other signage and promotions at retail is a critical tobacco-control policy to reduce people's exposure to tobacco marketing. Exposure to point-of-sale (POS) tobacco promotions is associated with adolescent smoking initiation, 1 – 6 impulse cigarette purchases, 7 , 8 and relapse among those trying to quit. 9 Furthermore, youths exposed to POS promotions exhibit higher levels of brand recognition and positive imagery of tobacco products. 10 POS promotions are more prominent in low-income neighborhoods, 11 – 13 stores near schools, 12 areas near schools with high smoking prevalence, 14 and shopping areas frequented more often by adolescents. 15 In Ontario, Canada, a phased-in ban on the retail display of tobacco products was implemented over 2 years. Initial restrictions on promotions (powerwall enhancements, countertop displays, most signage) took effect on May 31, 2006, followed by a full POS display ban on all tobacco products on May 31, 2008. To investigate the impact of this government policy, we conducted a longitudinal study of tobacco promotions in a cohort of stores over a 4-year period before, during, and after full implementation of the tobacco retail display ban.
