Expanding population-level interventions to help more low-income smokers quit: Study protocol for a randomized controlled trial.

Background: Low-income Americans have higher rates of smoking and a greater burden of smoking-related disease. In the United States, smokers in every state can access evidence-based telephone counseling through free tobacco quitlines. However, quitlines target smokers who are ready to quit in the next 30 days, which can exclude many low-income smokers. A smoke-free homes intervention may help engage smokers in tobacco control services who are not yet ready to quit. Previous research in low-income populations suggests that receiving a smoke-free homes intervention is associated with higher quit rates. This study tests whether, at a population level, expanding on quitlines to include a smoke-free homes intervention for smokers not ready to quit could engage more low-income smokers and increase long-term cessation rates.

Methods: In a Hybrid Type 2 design, participants are recruited from 211 helplines in 9 states and randomly assigned to standard quitline or quitline plus smoke-free homes intervention arms. Participants in both arms are initially offered quitline services. In the quitline plus smoke-free homes condition, participants who decline the quitline are then offered a smoke-free homes intervention. Participants complete a baseline and follow-up surveys at 3 and 6 months. Those who have not yet quit at the 3-month follow-up are re-offered the interventions, which differ by study arm. The primary study outcome is self-reported 7-day point prevalence abstinence from smoking at 6-month follow-up.

Conclusion: This real-world cessation trial involving 9 state tobacco quitlines will help inform whether offering smoke-free homes as an alternative intervention could engage more low-income smokers with evidence-based interventions and increase overall cessation rates. This study has been registered at ClinicalTrials.gov (Study Identifier: NCT04311983).