By Tarun Sai Lomte May 12 2023 Reviewed by Lily Ramsey, LLM

In a recent study published in the eClinicalMedicine Journal, researchers assessed the levels of public support for smoke-free policies in indoor (semi)-private and outdoor areas.

Study:  Public support for smoke-free policies in outdoor areas and (semi-)private places: a systematic review and meta-analysis. Image Credit: LuckyBusiness/Shutterstock.com Background

Second-hand smoke exposure is a significant burden to global public health. Evidence suggests that legislation to protect people from smoke in workplaces and indoor public spaces can decrease the harmful effects of tobacco smoke. Several jurisdictions have extended smoke-free policies to include outdoor and private places.

Public support is critical for policymakers to implement such policies and maximize compliance. Prior studies have observed differences in support within populations and between smoke-free places.

Therefore, it is crucial to gain insights into the determinants and levels of public support for such policies to inform policymaking regarding their expansion covering outdoor and semi-private spaces. About the study

In the present study, researchers systematically reviewed the evidence on public support levels for smoke-free policies encompassing semi-private and outdoor places.

They searched Embase, Medline, Cochrane, PsycINFO, Web of Science, and the cumulative index to nursing and allied health literature (CINAHL) databases for studies published from January 2004 to January 2022, with no restrictions on language.

Studies were eligible if they assessed support for policies in indoor private or semi-private spaces, outdoor hospitality or non-hospitality places, and outdoor semi-private places, with policies already implemented, planned, or hypothetical.

Studies were excluded if the sample size was <400, only non-combustible tobacco products were covered, or support was reported for workplaces or indoor public places. Related StoriesResearchers map the immune system in the gut of kids with inflammatory bowel diseaseGun assault rates doubled for children in 4 major cities during the pandemic, new data showsExperts urge increased attention to the threat of climate change and pollution on children's health

Titles/abstracts and full texts were screened to identify eligible reports, and relevant data were extracted from included studies.

The risk of bias in included studies was assessed using the mixed methods appraisal tool. Logit transformations were applied if support was reported as proportions ranging from zero to one.

If reported as the average score on the Likert scale, it was transformed to the proportion support. A three-level meta-analysis accounted for between-study, within-study, and country-level clustering. Sub-group analyses were also performed by gender, age group, parental status, and smoking status. Findings

The authors identified more than 14,500 records from the databases. Duplicates and pre-2004 studies were removed, resulting in over 6,000 records for screening. Overall, 107 studies from 33 countries were included for analysis.

Sixty-seven studies investigated support for hypothetical scenarios, 36 investigated public support for implemented policies, and four assessed public support for policies likely to be introduced or extended.

Forty-two studies were considered to have a low risk of bias, and 65 were deemed as having a moderate or high risk of bias. Eight studies were excluded from the meta-analysis. The meta-analysis included data from almost 900,000 participants.

The highest public support levels for smoke-free places were for private indoor spaces (73%) and semi-private indoor places (70%). Public support for policies in outdoor non-hospitality and hospitality places was 69% and 50%, respectively.

For semi-private outdoor places, support was 67%. The lowest support was for outdoor private places (41%). Public support was the highest for making cars with children onboard smoke-free at 86%, followed by playgrounds and school grounds at 80% and 76%, respectively.

Parks, beaches, and outdoor hospitality or private places had the lowest public support. There was substantial heterogeneity within or between studies and between countries.

Support was significantly higher among ex- or non-smokers than among current smokers. Females were significantly more often in favor of policies than males.

People in low- and middle-income countries (LMICs) had similar levels of support for policies as those from high-income countries, except for higher support for outdoor non-hospitality policies in LMICs.

Twelve studies assessed public support for policies pre- and post-implementation. Six reported that support was significantly higher after implementation, whereas others did not find significant changes. Sensitivity analyses found no significant differences in support between studies with a low and high risk of bias, indicating that the evidence was robust. Conclusions

The authors observed that public support for smoke-free policies covering outdoor and semi-private spaces was particularly high for places where children are commonly present, such as playgrounds, school grounds, and cars with children.

Support was more than 50% or higher for all areas except private outdoor spaces. Ex- and non-smokers were more in support of policies than smokers.

The findings suggest high support for smoke-free spaces covering outdoor and semi-private areas from the surveyed populations. Policymakers should proceed with further steps in protecting the public, especially children, from the adverse effects of smoke exposure by expanding smoke-free policies. Journal reference:

Boderie, N.W., Sheikh, A., Lo, E., Sheikh, A., Burdorf, A., Van Lenthe, F.J., Mölenberg, F.J.M. & Been, J.V. (2023) Public support for smoke-free policies in outdoor areas and (semi-)private places: a systematic review and meta-analysis. eClinicalMedicine, p.101982. doi: 10.1016/j.eclinm.2023.101982. https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(23)00159-1/fulltext