Peer effects in smoking cessation: An instrumental variables analysis of a worksite intervention in Thailand

Transitions between tobacco products: Correlates of changes in cigarette smoking and e-cigarette use among exclusive adult smokers and dual users in Mexico

This study examined transitions in tobacco products use among Mexican smokers and dual users. Data were analyzed from exclusive smokers (n = 2,946) and dual users (n = 1,643) recruited from an online consumer research panel and surveyed every-four months from November 2018 to April 2021. For exclusive smokers, estimated transitions were (time "t + 1" four months after prior survey): a) remain as exclusive smokers; b) dual use; c) exclusive e-cigarette use or quit both products. Among dual users, transitions analyzed were: a) remain as dual user; b) exclusive smoker; c) exclusive e-cigarette user or quit both products. Multinomial models regressed transitions at "t + 1" on time "t" for control variables. Most exclusive smokers (81%) remained as such, 12.6% transitioned to dual use, 2.3% to exclusive e-cigarette use, and 4% quitted both products. Exclusive smokers were more likely to transition to dual use if they recently attempted to quit (AOR = 1.45) or had partners/family or friends who used e-cigarettes (AOR = 2.47 & 2.56 respectively). Most dual users (74.8%) remained as dual users, 20.4% transitioned to exclusive smoking, 1.6% transitioned to exclusive e-cigarette use, and 3.2% quitted both products. Dual users were more likely to transition to exclusive smoking if they had lower educational attainment, recently attempted to quit e-cigarettes (AOR = 1.70). Having friends who use e-cigarettes (AOR = 0.29) and higher smoking dependence (AOR = 0.55) were associated with a lower likelihood of quitting. Recent quit attempts and e-cigarette use among close social network members may explain the short-term transitions, though longer follow-up is needed to assess sustained smoking cessation.

Incentive programmes for smoking cessation: cluster randomized trial in workplaces in Thailand

OBJECTIVE

To compare several monetary incentive programmes for promoting smoking abstinence among employees who smoke at workplaces in a middle income country.

DESIGN

Parallel group, open label, assessor blinded, cluster randomized controlled trial.

SETTING

Large industrial workplaces in metropolitan Bangkok, Thailand.

PARTICIPANTS

Employees who smoked cigarettes and planned to quit within six months recruited from 101 worksite clusters (84 different companies).

INTERVENTIONS

Worksites were digitally cluster randomized by an independent investigator to usual care or usual care plus one of eight types of incentive programmes. Usual care consisted of one time group counseling and cessation support through a 28 day text messaging programme. The incentive programmes depended on abstinence at three months and varied on three intervention components: refundable deposits, assignment to a teammate, and bonus size ($20 (£15; €17) or $40).

MAIN OUTCOME MEASURES

The primary outcome was biochemically verified seven day point prevalence smoking abstinence at 12 months. Secondary outcomes were programme acceptance at enrollment and smoking abstinence at three months (end of intervention) and at six months. All randomized participants who had complete baseline information were included in intention-to-treat analyses; participants with missing outcomes were coded as continuing smokers.

RESULTS

Between April 2015 and August 2016, the trial enrolled 4190 participants. Eighteen were omitted because of missing baseline covariates and death before the primary endpoint, therefore 4172 participants were included in the intention-to-treat analyses. Programme acceptance was relatively high across all groups: 58.7% (2451/4172) overall and 61.3% (271/442) in the usual care group. Abstinence rates at 12 months did not differ among deposit programmes (336/2253, 14.9%) and non-deposit programmes (280/1919, 14.6%; adjusted difference 0.8 points, 95% confidence interval -2.7 to 4.3, P=0.65), but were somewhat lower for team based programmes (176/1348, 13.1%) than individual based programmes (440/2824, 15.6%; -3.2 points, -6.6 to -0.2, P=0.07), and higher for $40 bonus programmes (322/1954, 16.5%) than programmes with no bonus (148/1198, 12.4%; 5.9 points, 2.1 to 9.7, P=0.002). The $40 individual bonus was the most efficacious randomization group at all endpoints. Intervention components did not strongly interact with each other.

CONCLUSIONS

Acceptance of monetary incentive programmes for promoting smoking abstinence was high across all groups. The $40 individual bonus programmes increased long term smoking abstinence compared with usual care, although several other incentive designs did not, such as team based programmes and deposit programmes. Incentive design in workplace wellness programmes might influence their effectiveness at reducing smoking rates in low resource settings.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT02421224).