Effectiveness of Instant Messaging-Based Online Group Support for Preventing Smoking Relapse: a Pragmatic Randomized Controlled Trial

Online group support potentially help prevent smoking relapse. This two-arm, pragmatic, open-label randomized controlled trial assessed the effectiveness of instant messaging (IM) (i.e., WhatsApp) online group support versus text messages for smoking relapse prevention. The intervention group ( n = 469) participated in 8-week counsellor-moderated IM-based online discussion groups and receive messages on preventing relapse via WhatsApp. The control group ( n = 459) received similar messages via text messaging for 8 weeks. Primary outcome was biochemically validated tobacco abstinence (exhaled carbon monoxide < 4 parts per million; or saliva cotinine < 10 ng/ml) at 12-month follow-up. By intention-to-treat, intervention and control groups showed similar prevalence of biochemically validated abstinence (11.9% versus 11.7%, risk ratio [RR] = 1.01; 95%CI 0.71–1.44; P = 0.93). The interactive IM-based online group support was costly but did not increase smoking abstinence compared to simple text messaging. More interactive digital health interventions are more costly but may not be more effective than simple text messaging. ClinicalTrials.gov Identifier: # NCT03717051.