Compliance with smoke-free policies in outdoor settings: a realist review

Objective: Although smoke-free outdoor environments are increasingly implemented to reduce adolescent smoking and de-normalize the behaviour, compliance is often low. To better understand compliance of people who smoke, we conducted a realist review. Methods: A realist review, a type of literature review, uses existing evidence to make a program theory, outlining mechanisms and contexts, that provides an explanatory analysis of compliance of people who smoke with outdoor smoke-free environments. The search was conducted in PubMed, Web of Science, Embase, and PsycINFO. Studies were included that had been published from January 1, 2000, to September 1, 2023. Twenty-five peer-reviewed English-language articles were included. Evidence was extracted about contexts and mechanisms that influence the compliance of smokers. Results: Compliance with smoke-free outdoor environments increases if people who smoke accept the policy, have sufficient knowledge and when the policy affects their motivation to quit smoking. However, these mechanisms may be hindered by feelings of people who smoke, such as low confidence in the policy's effectiveness and enforcement, feelings of stigma, and a lack of understanding. The context in which these environments are implemented, such as communication about the smoke-free policy, the stop-smoking facilities, the presence of ashtrays and designated smoking areas, and the size of the environment, influences mechanisms and compliance. Conclusions: To increase acceptance and clarity of smoke-free policies, we recommend implementing smoke-free outdoor policies without designated smoking areas or ashtrays while actively promoting public awareness. To avoid stigmatisation, accessible cessation support is key. Lastly, proper enforcement training is essential.