Can visual nudges reduce smoking tobacco expenditure? Evidence from a clustered randomized controlled trial in rural Bangladesh

IntroductionA household-level constant visual deterrent advocacy campaign to reduce tobacco intake was conducted in rural Bangladesh.AimsTo evaluate smoking tobacco expenditure by campaign components.MethodsWe conducted a single-blind clustered randomized controlled trial on 630 adult male household heads from 16 chars (riverine islands) in rural northern Bangladesh, between November 2018 and January 2019. Intervention allotment was randomized at the char level to minimize spillovers, with 8 chars in treatment and control groups each. The intervention provided households in treatment chars (n = 323) with two visual warning posters, detailing the health effects of tobacco on oneself and external actors, to be hung inside the household for 4 weeks. Households in control chars (n = 307) received nothing. Reported daily smoking (log) tobacco expenditure values were the primary outcome of interest.ResultsFinal analysis was conducted using 251 and 210 smokers in treatment and control chars respectively. The intervention reduced relative smoking tobacco expenditure by 12.8% (95% CI −31.45 to 5.81) but was not statistically significant (P-value = 0.163). Weak to moderate emotional reactions to the posters was identified as a reason for the statistical insignificance.ConclusionFor a visual anti-tobacco intervention to have a substantial impact, it must induce strong emotional responses.