School holidays and respiratory syncytial virus transmission in Sweden: An interrupted time series analysis.

AIM: Respiratory syncytial virus (RSV) represents a significant cause of morbidity for children worldwide, especially for newborns. As RSV vaccines are not routinely used for children yet, non-pharmaceutical interventions (NPIs) represent the main strategy for prevention. The objective of this study was to investigate the correlation between school holidays and RSV transmission. METHODS: Data were collected from the weekly reports on RSV incidence for the 2021/2022 and 2022/2023 seasons in Sweden. The 7-day cumulative incidence of RSV was compared before and after the designated school holidays (Fall, Christmas, and Winter holidays). RESULTS: Our findings reveal an immediate (-1.7%, p < 0.001, 95% CI [-3.1%, -0.4%]) and gradual (-1.4%/week, p < 0.001, 95%CI [-1.8, -1.0]) reduction in RSV incidence following the Fall holiday in 2021, especially among children under 1 year of age, both immediately (-107.6%, p < 0.05, 95% CI [-203.7, -11.5]) and gradually afterwards (-58.5%/week, p < 0.001, 95% CI [-72.7, -44.3]). Mixed results were obtained for the Fall in 2022/2023 and for the Winter and holidays in both the studied years. CONCLUSIONS: While the Fall holiday in 2021/2022 was associated with a decrease in RSV incidence in Sweden, our results do not support a universal effect of school holidays on reducing RSV transmission.

Association of time spent on social media with youth cigarette smoking and e-cigarette use in the UK: a national longitudinal study.

BACKGROUND: Social media may influence children and young people's health behaviour, including cigarette and e-cigarette use. METHODS: We analysed data from participants aged 10-25 years in the UK Household Longitudinal Study 2015-2021. The amount of social media use reported on a normal weekday was related to current cigarette smoking and e-cigarette use. Generalised estimating equation (GEE) logistic regression models investigated associations of social media use with cigarette smoking and e-cigarette use. Models controlled for possible confounders including age, sex, country of UK, ethnicity, household income and use of cigarette/e-cigarettes by others within the home. RESULTS: Among 10 808 participants with 27 962 observations, current cigarette smoking was reported by 8.6% of participants for at least one time point, and current e-cigarette use by 2.5% of participants. In adjusted GEE models, more frequent use of social media was associated with greater odds of current cigarette smoking. This was particularly apparent at higher levels of use (eg, adjusted odds ratio (AOR) 3.60, 95% CI 2.61 to 4.96 for ≥7 hours/day vs none). Associations were similar for e-cigarettes (AOR 2.73, 95% CI 1.40 to 5.29 for ≥7 hours/day social media use vs none). There was evidence of dose-response in associations between time spent on social media and both cigarette and e-cigarette use (both p<0.001). Analyses stratified by sex and household income found similar associations for cigarettes; however, for e-cigarettes associations were concentrated among males and those from higher household income groups. CONCLUSIONS: Social media use is associated with increased risk of cigarette smoking and e-cigarette use. There is a need for greater research on this issue as well as potential policy responses.

Socio-economic inequalities in smoking and drinking in adolescence: Assessment of social network dynamics.

AIMS: We investigated whether (1) adolescents selected friends with a similar socio-economic status (SES), (2) smoking and alcohol consumption spread in networks and (3) the exclusion of non-smokers or non-drinkers differed between SES groups. DESIGN: This was a longitudinal study using stochastic actor-oriented models to analyze complete social network data over three waves. SETTING: Eight Hungarian secondary schools with socio-economically diverse classes took part. PARTICIPANTS: This study comprised 232 adolescents aged between 14 and 15 years in the first wave. MEASUREMENTS: Self-reported smoking behavior, alcohol consumption behavior and friendship ties were measured. SES was measured based upon entitlement to an income-tested regular child protection benefit. FINDINGS: Non-low-SES adolescents were most likely to form friendships with peers from their own SES group [odds ratio (OR) = 1.07, 95% confidence interval (CI) = 1.02-1.11]. Adolescents adjusted their smoking behavior (OR = 24.05, 95% CI = 1.27-454.86) but not their alcohol consumption (OR = 1.65, 95% CI = 0.62-4.39) to follow the behavior of their friends. Smokers did not differ from non-smokers in the likelihood of receiving a friendship nomination (OR = 0.98, 95% CI = 0.87-1.10), regardless of their SES. Alcohol consumers received significantly more friendship nominations than non-consumers (OR = 1.16, 95% CI = 1.01-1.33), but this association was not significantly different according to SES. CONCLUSIONS: Hungarian adolescents appear to prefer friendships within their own socio-economic status group, and smoking and alcohol consumption spread within those friendship networks. Socio-economic groups do not differ in the extent to which they encourage smoking or alcohol consumption.

Associations of social media use with smoking and e-cigarettes: a national longitudinal study.

BACKGROUND: Social media use is high among children and young people and might influence health behaviours. We examined social media use and use of tobacco and e-cigarettes in the UK. METHODS: We used data from participants aged 10-25 years from the UK Household Longitudinal Study (January 2015-January 2022). Participants were asked: "On a normal weekday, that is Monday to Friday, how many hours do you spend chatting or interacting with friends through a social website or app like that?". Specific social media platforms were not specified. Responses were none, less than 1 h, 1-3 h, 4-6 h, 7 h or more. Outcomes were current tobacco smoking and e-cigarette use. Generalised Estimating Equation (GEE) logistic regression models investigated associations of social media use with tobacco and e-cigarette use, and fixed effects analyses investigated changes in social media use with uptake of both products. Models included possible confounders such as age, sex, household income, ethnicity (White vs non-White) and use of tobacco or e-cigarettes by others within the home. All participants gave written informed consent. FINDINGS: The analytic sample included 10 808 participants with 27 962 observations (mean age 15·7 years [SD 3·8], 5080 [47%] male, 5728 [53%] female, and 7868 [73%] White). Current tobacco smoking was reported at one or more timepoints by 929 (8·6%) participants, and current e-cigarette use by 270 (2·5%) participants. In adjusted GEE models, all levels of social media use were associated with greater odds of current smoking than no use. This association was particularly apparent at higher levels of use adjusted odds ratio [aOR] 3·11, 95% CI 2·41-4·03 for ≥7 h use vs no use), with similar associations for e-cigarettes (aOR 3·04, 2·11-4·40 for ≥7 h use vs no use). Fixed effects analyses also found increased use of social media to be associated with increased uptake of both products (eg, changing to using social media for ≥7 h/day was associated with >2 times the odds of taking up tobacco smoking [aOR 2·33, 1·28-4·24]). INTERPRETATION: These analyses suggest an association between social media use and e-cigarette and tobacco use. Potential pathways include promotion of these products on social media. Further research with details on specific platforms would be useful as well as with longer follow-up time. FUNDING: Cancer Research UK.

Patterns of cigarette and e-cigarette use among UK adolescents: a latent class analysis of the Millennium Cohort Study.

BACKGROUND: Patterning of cigarette and e-cigarette use among young people remains poorly characterized. We aimed to describe these patterns in the UK Millennium Cohort Study at age 14 and 17 years. METHODS: Data on cigarette and e-cigarette use come from 9731 adolescents. Latent class analysis assigned participants to membership of classes of product use and multinomial logistic regression analyses assessed differences in the likelihood of belonging to classes by sociodemographic (age, gender, ethnicity, household income, maternal education and country of residence) and smoking-related social factors (caregiver tobacco use, caregiver e-cigarette use and peer smoking). RESULTS: We identified four classes of use: 45.8% of adolescents 'continued to abstain' from cigarettes or e-cigarettes; 21.3% 'experimented' (used once or in the past but not currently) with cigarettes and/or e-cigarettes by age 17 but were not current users; 19.0% were 'late adopters', characterized by low levels of use at age 14 but high levels of experimentation and current use at age 17; and 13.9% were 'early adopters', characterized by high levels of experimentation and current use at ages 14 and 17. At age 17, 70.4% of 'early adopters' smoked cigarettes regularly plus an additional 27.3% experimented with cigarettes. Corresponding percentages for e-cigarettes were 37.9% and 58.9%. Tobacco and e-cigarette use by caregivers, and cigarette use by peers, were associated with being both 'late adopters' and 'early adopters'. CONCLUSIONS: Approximately one in seven adolescents in the UK are 'early adopters' of nicotine products. This highlights the need to develop and implement effective policies to prevent nicotine use uptake.

Multistate transition modelling of e-cigarette use and cigarette smoking among youth in the UK.

INTRODUCTION: E-cigarette use remains a controversial topic, with questions over how people transition between e-cigarette use and cigarette smoking. This paper examined transitions into and out of nicotine product use in a representative sample of UK youth. METHODS: We used Markov multistate transition probability models on data from 10 229 participants (10-25 years old) in the UK Household Longitudinal Study (2015-2021). We used four product use states ('never', 'non-current use', 'e-cigarette only' and 'smoking and dual use') and estimated likelihood of transitions according to sociodemographic characteristics. RESULTS: Among participants who had never used nicotine products, most were still non-users a year later (92.9% probability; 95% CI 92.6%, 93.2%); a small proportion transitioned to using e-cigarettes only (4.0%; 95% CI 3.7%, 4.2%) and cigarettes (2.2%; 95% CI 2.0%, 2.4%). Those aged 14-17 years were the most likely to start using a nicotine product. E-cigarette use was less persistent overtime than cigarette smoking, with a 59.1% probability (95% CI 56.9%, 61.0%) of e-cigarette users still using after 1 year compared with 73.8% (95% CI 72.1%, 75.4%) for cigarette smoking. However, there was a 14% probability (95% CI 12.8%, 16.2%) that e-cigarette users went onto smoke cigarettes after 1 year, rising to 25% (95% CI 23%, 27%) after 3 years. CONCLUSION: This study found that although overall nicotine product use was relatively rare, participants were more likely to experiment with e-cigarette use than cigarette smoking. This was mostly not persistent over time; however, approximately one in seven transitioned to cigarette smoking. Regulators should aim to deter all nicotine product use among children.

Effect of comprehensive smoke-free legislation on neonatal mortality and infant mortality across 106 middle-income countries: a synthetic control study.

BACKGROUND: There are few quantitative studies into the effect of comprehensive smoke-free legislation on neonatal and infant mortality in middle-income countries. We aimed to estimate the effects of implementing comprehensive smoke-free legislation on neonatal mortality and infant mortality across all middle-income countries. METHODS: We applied the synthetic control method using 1990-2018 country-level panel data for 106 middle-income countries from the WHO, World Bank, and Penn World datasets. Outcome variables were neonatal (age 0-28 days) mortality and infant (age 0-12 months) mortality rates per 1000 livebirths per year. For each middle-income country with comprehensive smoke-free legislation, a synthetic control country was constructed from middle-income countries without comprehensive smoke-free legislation, but with similar prelegislation trends in the outcome and predictor variables. Overall legislation effect was the mean average of country-specific effects weighted by the number of livebirths. We compared the distribution of the legislation effects with that of the placebo effects to assess the likelihood that the observed effect was related to the implementation of smoke-free legislation and not merely influenced by other processes. FINDINGS: 31 (29%) of 106 middle-income countries introduced comprehensive smoke-free legislation and had outcome data for at least 3 years after the intervention. We were able to construct a synthetic control country for 18 countries for neonatal mortality and for 15 countries for infant mortality. Comprehensive smoke-free legislation was followed by a mean yearly decrease of 1·63% in neonatal mortality and a mean yearly decrease of 1·33% in infant mortality. An estimated 12 392 neonatal deaths in 18 countries and 8932 infant deaths in 15 countries were avoided over 3 years following the implementation of comprehensive smoke-free legislation. We estimated that an additional 104 063 infant deaths (including 95 850 neonatal deaths) could have been avoided over 3 years if the 72 control middle-income countries had introduced this legislation in 2015. 220 (43%) of 514 placebo effects for neonatal mortality and 112 (39%) of 289 for infant mortality were larger than the estimated aggregated legislation effect, indicating a degree of uncertainty around our estimates. Sensitivity analyses showed results that were consistent with the main analysis and suggested a dose-response association related to comprehensiveness of the legislation. INTERPRETATION: Implementing comprehensive smoke-free legislation in middle-income countries could substantially reduce preventable deaths in neonates and infants. FUNDING: Dutch Heart Foundation, Lung Foundation Netherlands, Dutch Cancer Society, Dutch Diabetes Research Foundation, Netherlands Thrombosis Foundation, Health Data Research UK.

Pediatric patients' views regarding smoke-free hospital grounds compared to those of adults: A survey study.

INTRODUCTION: Children are important stakeholders in discussions about regulation of smoking and protection from secondhand smoke, but are rarely acknowledged as such. We explored the opinion of pediatric patients and other key stakeholders regarding the planned smoke-free zone around the Erasmus MC, a large university hospital in the Netherlands. METHODS: In 2019, we conducted a survey among pediatric patients and their parents, Erasmus MC employees, visitors, and adult patients, before implementation of the outdoor smoke-free zone, to assess their opinions on smoking and the planned smoke-free policy. Qualitative and quantitative data were collected and analyzed mostly using descriptive statistics and thematic analysis. RESULTS: In all, 91 parent-child dyads and 563 employees, visitors, patients and students filled in the questionnaires. Over 90% of children reported that they were regularly exposed to tobacco smoke, most often on the streets. Many underlined the exemplary role of healthcare providers, and 89% felt that nobody should be allowed to smoke near the hospital. Among parents, 89% were (very) positive towards the planned implementation of the smoke-free zone. In addition, 70% of adult patients, 81% of employees, 65% of visitors, 89% of students and 75% of 'others' were (very) positive about the new smoke-free policy. Smokers and former smokers generally were less positive about the policy. CONCLUSIONS: Children generally disapproved smoking around a hospital and felt that healthcare providers should be a good example concerning not smoking. The majority of adult patients, employees and visitors support a smoke-free zone surrounding the hospital, and virtually all pediatric patients and their parents do. Children should be acknowledged as important stakeholders in smoke-free policies and should be involved in planning and implementation.

Cigarette taxation and neonatal and infant mortality: A longitudinal analysis of 159 countries.

Previous studies on the associations between cigarette taxes and infant survival have all been in high-income countries and did not examine the relative benefits of different taxation levels and structures. We evaluated longitudinal associations of cigarette taxes with neonatal and infant mortality globally. We applied country-level panel regressions using 2008-2018 annual mortality and biennial WHO tobacco taxation data. Complete data was available for 159 countries. Outcomes were neonatal and infant mortality. We conducted analyses by type of taxes (i.e. specific cigarette taxes, ad valorem taxes, and other taxes, import duties and VAT) and the income group classification of countries. Covariates included scores for other WHO recommended tobacco control policies, socioeconomic, health-care, and air quality measures. Secondary analyses investigated the associations between cigarette tax and cigarette consumption. We found that a 10 percentage-point increase in total cigarette tax as a percentage of the retail price was associated with a 2.6% (95% Confidence Interval [CI]: 1.9% to 3.2%) decrease in neonatal mortality and a 1.9% (95% CI: 1.3% to 2.6%) decrease in infant mortality globally. Estimates were similar for both excise and ad valorem taxes. We estimated that 231,220 (95% CI: 152,658 to 307,655) infant deaths could have been averted in 2018 if all countries had total cigarette tax at least 75%. 99.2% of these averted deaths would have been in low- and middle-income countries (LMICs). The secondary analysis supported causal interpretation of results by finding that a 10 percentage-point increase in taxes was associated with a reduction of 94.6 (95% CI: 32.7 to 156.5) in annual cigarette consumption per capita. Although causal inference is precarious due to the quasi-experimental design, we used a robust analytical approach and focused on within-country changes. Limitations include an inability to include data on roll-your-own tobacco, other forms of tobacco use, and reliance on taxation data only for the cigarette brands most sold in each country. In line with limited existing evidence conducted in HICs, we found that raising taxes on tobacco was associated with a reduction in neonatal and infant mortality globally. Implementing recommended levels of taxation in LMICs should be a priority since this is where the lowest levels of taxation and the largest potential infant mortality benefits exist.

Effect of smoke-free policies in outdoor areas and private places on children's tobacco smoke exposure and respiratory health: a systematic review and meta-analysis.

BACKGROUND: Smoke-free policies in outdoor areas and semi-private and private places (eg, cars) might reduce the health harms caused by tobacco smoke exposure (TSE). We aimed to investigate the effect of smoke-free policies covering outdoor areas or semi-private and private places on TSE and respiratory health in children, to inform policy. METHODS: In this systematic review and meta-analysis, we searched 13 electronic databases from date of inception to Jan 29, 2021, for published studies that assessed the effects of smoke-free policies in outdoor areas or semi-private or private places on TSE, respiratory health outcomes, or both, in children. Non-randomised and randomised trials, interrupted time series, and controlled before-after studies, without restrictions to the observational period, publication date, or language, were eligible for the main analysis. Two reviewers independently extracted data, including adjusted test statistics from each study using a prespecified form, and assessed risk of bias for effect estimates from each study using the Risk of Bias in Non-Randomised Studies of Interventions tool. Primary outcomes were TSE in places covered by the policy, unplanned hospital attendance for wheezing or asthma, and unplanned hospital attendance for respiratory tract infections, in children younger than 17 years. Random-effects meta-analyses were done when at least two studies evaluated policies that regulated smoking in similar places and reported on the same outcome. This study is registered with PROSPERO, CRD42020190563. FINDINGS: We identified 5745 records and assessed 204 full-text articles for eligibility, of which 11 studies met the inclusion criteria and were included in the qualitative synthesis. Of these studies, seven fit prespecified robustness criteria as recommended by the Cochrane Effective Practice and Organization of Care group, assessing smoke-free cars (n=5), schools (n=1), and a comprehensive policy covering multiple areas (n=1). Risk of bias was low in three studies, moderate in three, and critical in one. In the meta-analysis of ten effect estimates from four studies, smoke-free car policies were associated with an immediate TSE reduction in cars (risk ratio 0·69, 95% CI 0·55-0·87; 161 466 participants); heterogeneity was substantial (I2 80·7%; p<0·0001). One additional study reported a gradual TSE decrease in cars annually. Individual studies found TSE reductions on school grounds, following a smoke-free school policy, and in hospital attendances for respiratory tract infection, following a comprehensive smoke-free policy. INTERPRETATION: Smoke-free car policies are associated with reductions in reported child TSE in cars, which could translate into respiratory health benefits. Few additional studies assessed the effect of policies regulating smoking in outdoor areas and semi-private and private places on children's TSE or health outcomes. On the basis of these findings, governments should consider including private cars in comprehensive smoke-free policies to protect child health. FUNDING: Dutch Heart Foundation, Lung Foundation Netherlands, Dutch Cancer Society, Dutch Diabetes Research Foundation, Netherlands Thrombosis Foundation, and Health Data Research UK.

Impact of an Inner-City Smoke-Free Zone on Outdoor Smoking Patterns: A Before-After Study.

INTRODUCTION: On September 2, 2019, Rotterdam's first inner-city outdoor smoke-free zone encompassing the Erasmus MC, a large university hospital in the Netherlands, the Erasmiaans high school, the Rotterdam University of Applied Sciences and the public road in between, was implemented. AIMS AND METHODS: We aimed to assess spatiotemporal patterning of smoking before and after implementation of this outdoor smoke-free zone. We performed a before-after observational field study. We systematically observed the number of smokers, and their locations and characteristics over 37 days before and after implementation of the smoke-free zone. RESULTS: Before implementation of the smoke-free zone, 4098 people smoked in the area every weekday during working hours. After implementation, the daily number of smokers was 2241, a 45% reduction (p = .007). There was an increase of 432 smokers per day near and just outside the borders of the zone. At baseline, 31% of the smokers were categorized as employee, 22% as student and 3% as patient. Following implementation of the smoke-free zone, the largest decreases in smokers were observed among employees (-67%, p value .004) and patients (-70%, p value .049). Before and after implementation, 21 and 20 smokers were visibly addressed and asked to smoke elsewhere. CONCLUSIONS: Implementation of an inner-city smoke-free zone was associated with a substantial decline in the number of smokers in the zone and an overall reduction of smoking in the larger area. Further research should focus on optimizing implementation of and compliance with outdoor smoke-free zones. IMPLICATIONS: A smoke-free outdoor policy has the potential to denormalize and discourage smoking, support smokers who want to quit, and to protect people from secondhand smoke exposure. Implementation of an inner-city smoke-free zone encompassing a large tertiary hospital and two educational institutions was associated with a substantial decline in the number of smokers in the zone, as well as in the larger area. Voluntary outdoor smoke-free zones can help reduce the number of smokers in the area and protect people from secondhand smoke. There is a need to explore effectiveness of additional measures to further improve compliance.

Do educational reforms increase or decrease health inequalities: A matter of methods?

Evaluating whether social policies reduce health inequalities is complicated by the fact that these upstream determinants may also change the socioeconomic distribution. Failure to account for these compositional changes may severely bias the effect estimation procedure. In this article, we illustrate how a health inequality impact assessment of a policy that (also) changes the socioeconomic distribution may produce biased results. First, we show why analyses that do not account for compositional changes fail to estimate the correct counterfactual outcome. This problem most notably occurs when using repeated cross-sectional data, often the only available option to evaluate the health effect of large-scale policies. Second, we conducted a microsimulation study to estimate the magnitude of the bias under various conditions. The results showed that the actual impact of the policy on health inequalities is often underestimated and may even produce results that are in the opposite direction of the actual causal effect of the policy. Future studies should explore new strategies, such as simulation methods, to assess the impact of policies that (also) cause changes in the socioeconomic composition of the population, to enable researchers to accurately estimate their effect on health inequalities.

Investigating the effects of comprehensive smoke-free legislation on neonatal and infant mortality in Thailand using the synthetic control method.

BACKGROUND: Almost all of the evidence on the benefits of smoke-free legislation on child health comes from evaluations in high-income countries. We investigated the effects of Thailand's 2010 comprehensive smoke-free legislation on neonatal and infant mortality. METHODS: To overcome some of the methodological issues inherent to traditional quasi-experimental methods, we applied the novel synthetic control approach. Using 2001-2017 country-level panel data from the World Bank and Penn World datasets, we estimated the effects of smoke-free legislation as the difference between the outcome trends in Thailand versus those in a synthetic control country. The synthetic control country was composed of 'control' middle-income countries without comprehensive smoke-free legislation to recreate trends in Thailand in the 2001-2009 pre-legislation outcomes and covariates. We compared the legislation effects to 'placebo effects' obtained for each control country by fictitiously assuming that comprehensive smoke-free legislation was introduced there in 2010, similar to Thailand. FINDINGS: Neonatal and infant mortality decreased by 2.9% and 2.8%/year respectively following smoke-free legislation, with an estimated 7463 infant deaths (including 4623 neonatal deaths) having been averted over eight years. The results were robust to different specifications of the control countries. Comparison with placebo effects indicated that the findings were unlikely to be attributable to factors other than the smoke-free legislation. INTERPRETATION: Expanding comprehensive smoke-free policies to middle-income countries can support national efforts to achieve Sustainable Development Goal 3.2 for reducing preventable early-life deaths. FUNDING: Netherlands Lung Foundation, HDRUK, Asthma UK center for Applied Research and NIHR Global Respiratory Health Unit (RESPIRE).

Impact of expanding smoke-free policies beyond enclosed public places and workplaces on children's tobacco smoke exposure and respiratory health: protocol for a systematic review and meta-analysis.

INTRODUCTION: Tobacco smoke exposure (TSE) has considerable adverse respiratory health impact among children. Smoke-free policies covering enclosed public places are known to reduce child TSE and benefit child health. An increasing number of jurisdictions are now expanding smoke-free policies to also cover outdoor areas and/or (semi)private spaces (indoor and/or outdoor). We aim to systematically review the evidence on the impact of these 'novel smoke-free policies' on children's TSE and respiratory health. METHODS AND ANALYSIS: 13 electronic databases will be searched by two independent reviewers for eligible studies. We will consult experts from the field and hand-search references and citations to identify additional published and unpublished studies. Study designs recommended by the Cochrane Effective Practice and Organisation of Care (EPOC) group are eligible, without restrictions on the observational period, publication date or language. Our primary outcomes are: self-reported or parental-reported TSE in places covered by the policy; unplanned hospital attendance for wheezing/asthma and unplanned hospital attendance for respiratory infections. We will assess risk of bias of individual studies following the EPOC or Risk Of Bias In Non-randomised Studies of Interventions tool, as appropriate. We will conduct separate random effects meta-analyses for smoke-free policies covering (1) indoor private places, (2) indoor semiprivate places, (3) outdoor (semi)private places and (4) outdoor public places. We will assess whether the policies were associated with changes in TSE in other locations (eg, displacement). Subgroup analyses will be conducted based on country income classification (ie, high, middle or low income) and by socioeconomic status. Sensitivity analyses will be undertaken via broadening our study design eligibility criteria (ie, including non-EPOC designs) or via excluding studies with a high risk of bias. This review will inform policymakers regarding the implementation of extended smoke-free policies to safeguard children's health. ETHICS AND DISSEMINATION: Ethical approval is not required. Findings will be disseminated to academics and the general public. PROSPERO REGISTRATION NUMBER: CRD42020190563.

PERSonalised Incentives for Supporting Tobacco cessation (PERSIST) among healthcare employees: a randomised controlled trial protocol.

BACKGROUND: Smoking is the primary preventable risk factor for disease and premature mortality. It is highly addictive and cessation attempts are often unsuccessful. Incentive-based programmes may be an effective method to reach sustained abstinence. Individualisation of incentives based on personal characteristics yields potential to further increase the effectiveness of incentive-based programmes. METHOD: A randomised controlled trial among healthcare workers recruited through their employer and signed up for a group-based smoking cessation programme. The intervention under study is the provision of personalised incentives on validated smoking cessation at several time points after the smoking cessation programme. A total of 220 participants are required. Participants are randomised 1:1 into intervention (personalised incentives) or control (no incentives). All participants join the group-based programme. Incentives are provided on validated abstinence directly after the smoking cessation programme and after 3, 6 and 12 months.Incentives are provided according to four schemes:(1) Standard: total reward size €350, pay-out scheme: €50 (t=0), €50 (t=3 months), €50 (t=6 months) and €200 (t=12 months), (2) descending: total reward size €300, pay-out scheme: €150, €100, €50 and €0, (3) ascending: total reward size: €400, pay-out scheme: €0, €0, €50 and €350 and (4) deposit: total reward size €450, pay-out scheme: €50, €50, €150, €200; participants pay a €100 deposit, returned conditional on abstinence after 6 months.Advice on which incentive scheme suits participants best is based on willingness to provide a deposit, readiness to quit, nicotine dependency and long-term or short-term reward preference. Participants are free to deviate from this advice. Abstinence is validated at each time point, with 15 months of total follow-up. The primary end point is validated abstinence at 12 months. Effectiveness will be determined by intention-to-treat analysis. ETHICS AND DISSEMINATION: The Erasmus MC Medical Ethics Committee decided that according to the Dutch Human Research Law (WMO), the protocol required no formal ethical approval. The results will be published in a peer-reviewed scientific journal and communicated to the participants. TRIAL REGISTRATION NUMBER: Netherlands Trial Register NL7711.