Effect of Smartphone-Based Financial Incentives on Peripartum Smoking Among Pregnant Individuals: A Randomized Clinical Trial

Cigarette smoking during pregnancy can cause serious adverse pregnancy, birth, and longer-term health outcomes.^1,2 The most efficacious smoking cessation intervention for peripartum individuals is abstinence-contingent financial incentives (FIs), but there are challenges to scaling this intervention, including reaching individuals in geographically remote areas while retaining treatment efficacy.^3,4 To address that challenge, this study examined the efficacy of a smartphone-based intervention whereby smoking monitoring and incentive delivery was managed via a mobile app.

This randomized clinical trial included 90 pregnant individuals aged 18 years or older who were recruited nationally via social media; obstetrical clinics; and Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) offices between April 2019 and May 2020. The trial protocol appears in Supplement 1. The University of Vermont College of Medicine institutional review board approved this study, and all participants provided written informed consent. The study follows Consolidated Standards of Reporting Trials (CONSORT) reporting guidelines for trial studies (eFigure in Supplement 2).

Participants were randomized to Best Practices (BP) alone or with FIs (BP with FI) (detailed previously).⁵ Briefly, BP included brief counseling and a tobacco quit-line referral. BP with FI included BP plus an FI intervention in which smoking monitoring and incentive delivery were completed via smartphone app (DynamiCare Health Inc). Participants submitted videos of themselves conducting salivary cotinine tests remotely (Alere iScreen [New Line Medical]) and received autogenerated notifications detailing test results and associated earnings. Incentives were delivered from study start to 12 weeks post partum via a debit card using an escalating schedule (maximum earnings, approximately $1620; mean [SD] earnings, $330.52 [$446.18]).⁵

All participants completed 6 assessments during study participation, including a 24-week postpartum assessment after incentives had been discontinued. There were no significant differences between treatment groups in assessment adherence. The primary outcome was 7-day point-prevalence abstinence (self-reported past week abstinence plus a cotinine-negative saliva test). Analyses of smoking-abstinence outcomes included all participants assigned to treatment, except 2 individuals withdrawn following miscarriage. A repeated-measures analysis for categorical data was used to compare treatment conditions on smoking abstinence across assessments based on generalized estimating equations using a logistic link function (SAS PROC GENMOD). Analyses were performed using SAS version 9 (SAS Institute), and a 2-tailed P < .05 was considered statistically significant.

Participant characteristics are provided in the Table. Of 167 eligible individuals who completed an initial study orientation session, 90 were enrolled (48 in the BP group; 42 in the BP with FI) across 33 states.

Individuals assigned to BP with FI had nearly 4-fold greater odds of smoking abstinence across antepartum and postpartum assessments compared with individuals receiving BP (χ²₁ = 6.96; adjusted odds ratio, 3.82; 95% CI, 1.63-8.92; P = .008) (Figure). Abstinence levels decreased across time (χ²₅ = 16.33; P = .006), with odds of abstinence lower at all postpartum assessment vs the initial antepartum assessment; time did not interact significantly with treatment condition (χ²₅ = 4.57; P = .47), indicating that abstinence levels in the BP with FI remained greater than those in the BP group through 24 weeks post partum.

The nearly 4-fold greater odds of quitting smoking among individuals treated with BP with FI vs BP alone is consistent with meta-analyses identifying FIs as the most effective intervention for peripartum individuals^3,6 and provides a seminal experimental demonstration that the intervention can be delivered remotely while retaining efficacy comparable with clinic-based outcomes.⁴ This successful treatment of a national, diverse participant sample highlights the capacity for the present innovative treatment delivery platform to expand the reach of this intervention to a broader swath of peripartum individuals, including those with socioeconomic disadvantage, rural residents, Indigenous individuals, and other racial and ethnic minority individuals. Limitations include the potential for internet-based recruitment to generate samples with higher socioeconomic status than recruiting via WIC offices⁴ and reduced precision in estimates of treatment effect size due to underenrollment.

Further research examining cost-effectiveness is an important next step in the development and dissemination of this treatment innovation. The present results underscore the considerable potential of this intervention for increasing peripartum smoking cessation, improving maternal-infant health, and reducing health disparities.

Accepted for Publication: March 27, 2022.

Published: May 13, 2022. doi:10.1001/jamanetworkopen.2022.11889

Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2022 Kurti AN et al. JAMA Network Open.

Corresponding Author: Allison N. Kurti, PhD, Vermont Center on Behavior and Health, the University of Vermont, One South Prospect Street, MS 482, Burlington, VT 05401 (Allison.kurti@uvm.edu).

Author Contributions: Dr Kurti and Mrs Skelly had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Kurti, Higgins.

Acquisition, analysis, or interpretation of data: All authors.

Drafting of the manuscript: Kurti, Nighbor, Bolivar, Higgins.

Critical revision of the manuscript for important intellectual content: All authors.

Statistical analysis: Skelly.

Obtained funding: Kurti.

Administrative, technical, or material support: Nighbor, Tang, Bolivar.

Supervision: Kurti, Higgins.

Conflict of Interest Disclosures: None reported.

Funding/Support: This work was supported in part by Centers of Biomedical Research Excellence award P20GM103644 from the National Institute on General Medical Sciences and research award R01HD075669 from the National Institute of Child Health and Human Development and US Centers for Disease Control and Prevention.

Role of the Funder/Sponsor: The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Trial Registration: ClinicalTrials.gov Identifier: NCT03922360

Data Sharing Statement: See Supplement 3.

Additional Contributions: Norman Medina, BA, helped with data collection, was compensated as a research assistant by the previously mentioned funding source, and has provided written permission to be included in the present acknowledgments for his nonauthor contributions.