Effect of Helpers Stay Quit Online Training on Preventing Smoking Relapse and Personal Networks: Protocol for a Pragmatic Randomized Controlled Trial and Embedded Mixed Methods Personal Network Study.

Background: Despite major gains in smoking cessation treatment, over half of those who recently quit will relapse within one year. Two systematic reviews of relapse prevention studies reached differing conclusions on the effectiveness of behavioral interventions. Existing relapse prevention evidence is limited by study designs, methodology, and conceptual approaches to behavioral interventions. Personal networks exert powerful effects on initiating and maintaining smoking behavior and can facilitate maintaining abstinence or trigger relapse. To date, relapse prevention interventions have focused on those who are newly abstinent ("abstainers") and have not attempted to influence the abstainer's personal network. The Helpers Stay Quit (Helpers Stay Quit) online training is a conceptually novel "help others" intervention to increase abstainers' public identification as a nonsmoker and their ability to influence those in their personal network to also quit smoking-thereby creating a personal network social environment supportive of long-term abstinence. Objective: This study is a 2-arm, pragmatic randomized controlled trial (pRCT) testing the hypothesis that quitline abstainers receiving the Helpers Stay Quit intervention will have higher 30-day and 7-day point prevalence of abstinence than those receiving quitline follow-up usual care, and that outcomes may be mediated by characteristics of abstainers' personal networks. The embedded mixed methods study examines the effects of the Helpers Stay Quit intervention on the abstainers' personal network interactions related to smoking and smoking cessation. Methods: The study design is a 2-group pRCT (N=940) comparing the Helpers Stay Quit online training intervention with a quitline usual care condition. Baseline, 3-, 6-, and 12-month surveys collect data on cognitive and emotional factors potentially influencing relapse. Text messages survey tobacco use status and participants' use of the Helpers Stay Quit training content. The composition and structure of participants' personal networks are assessed at baseline and 12 months. We interviewed 60 participants (both relapsed and abstinent) at differing intervals in the last 6 months of study participation to qualitatively assess personal network influences on relapse or abstinence. Results: A total of 9 state quitlines are participating by referring potentially eligible clients for screening and potential enrollment. Recruitment began in December 2022. Enrollment of 940 participants was completed in September 2025. When the manuscript was submitted, as of August 31, 2025, 337 participants (65%) had completed the study with 12-month follow-up surveys. Conclusions: This pRCT tests whether exposure to the Helpers Stay Quit intervention decreases relapse rates of newly abstinent smokers enrolled in state quitline coaching treatment. The embedded personal network mixed methods study is designed to examine the characteristics of a newly abstinent smoker's personal network that may influence relapse and the potential spread of cessation-related information and behaviors through their personal network. The study's design and measures will provide insights into the influences of personal networks and the cognitive and emotional factors impacting the likelihood of relapse or maintaining abstinence in those who are newly abstinent.