Efficacy of WeChat-based online smoking cessation intervention (‘WeChat WeQuit’) in China: a randomised controlled trial

BACKGROUND: China has approximately 300 million current smokers, and smoking cessation services are limited. This study aimed to assess the efficacy of a Cognitive Behavioral Theory-based smoking cessation intervention (‘WeChat WeQuit’) via the most popular social media platform in China, WeChat. METHODS: A parallel, single-blind, two-arm randomised controlled trial was conducted via WeChat between March 19, 2020 and November 16, 2022. Chinese-speaking adult smokers (n = 2000) willing to quit within one month were recruited and randomised in a 1:1 ratio. The intervention group (n = 1005) received the ‘WeChat WeQuit’ program and the control group (n = 955) received control messages for 14 weeks (2-week prequit and 12-week postquit). Participants were followed up to 26 weeks after the quit date. The primary outcome was self-reported continuous smoking abstinence rate, biochemically validated at 26 weeks. The secondary outcomes were self-reported 7-day and continuous abstinence rates at 6 months. All analyses were by intention to treat. The trial is registered at ClinicalTrials.gov (NCT03169686). FINDINGS: By intention-to-treat analysis, the biochemically verified 26-week continuous abstinence rate was 11.94% in the intervention group and 2.81% in the control group (OR = 4.68, 95% CI: 3.07–7.13, p < 0.0001). The self-reported 7-day abstinence rates ranged from 39.70% at week 1–32.04% at week 26 for the intervention group and 14.17%–11.86% in the control group for weeks 1 and 26, respectively; the self-reported continuous abstinence rates at weeks 1 and 26 ranged from 34.33% to 24.28% and 9.65% to 6.13% in the intervention group and the control group respectively (all p < 0.0001). Participants with low nicotine dependence or previous quit attempts were more likely to successfully quit smoking. INTERPRETATION: The ‘WeChat WeQuit’ intervention significantly increased smoking abstinence rates at 6 months and should be considered for treatment-seeking smokers in China. FUNDING: The research is supported by the Natural Science Foundation of Hunan Province (2020JJ4794, YLiao), the K.C. Wong Postdoctoral Fellowship for YLiao to study at King’s College London, and China Medical Board (CMB) Open Competition Program (grant no. 15-226, 22-485, YLiao).