Mediators of the Effect of Opt-in vs Opt-out Treatment on Smoking Cessation in a Randomized Clinical

Hu J, Gajewski B, Catley D, Faseru B, Bristi PD, Richter K.
Mediators of the Effect of Opt-in vs Opt-out Treatment on Smoking Cessation in a Randomized Clinical Trial
Nicotine Tob Res. 2025 Dec 24:ntaf265. doi: 10.1093/ntr/ntaf265. Epub ahead of print. PMID: 41439570; PMCID: PMC12758635.

Introduction: Smoking cessation interventions are effective. Most smokers do not receive them, in part because smokers are required to "opt-in". Changing The Default (CTD) randomized clinical trial, conducted at a large academic medical center, demonstrated that changing the default to providing treatment unless refused (opt-out) improved quit rates. The objective of this study was to evaluate if treatment participation and default-theory based variables explained the effect of opt-out on cessation.

Methods: We conducted a secondary analysis of CTD data (N=739). Descriptive statistics and correlations of the baseline variables were provided. Structural equation models were employed to investigate whether the treatment assignment was causally mediated by a priori proposed mediators including perceived endorsement, counseling participation, and medication utilization.

Results: The mean age of the participants was 51.39 (SD=14.71) years, among whom 349 (47.23%) were females, and the majority was White (428, 57.92%). The indirect effects from the opt-out treatment arm to counseling participation to smoking cessation (b= 0.201, 95% CI [0.105, 0.303]), from opt-out to perceived endorsement to counseling participation to smoking cessation (b = 0.010, 95% CI [0.002, 0.022]) were significant. The indirect effect from opt-out to perceived endorsement to counseling participation to medication utilization to smoking cessation was marginally significant (b=.001, 95% CI [0.000, 0.003]).

Conclusions: The opt-out approach enhanced patients' sense that their counselor endorsed and/or recommended treatment, as well as counseling participation. The results partially support our hypothesis that the advantage of Opt-out care would increase treatment participation and would do so by psychological variables thought to underpin the efficacy of defaults.