JMIR Publications

ABSTRACT

Background:

Cigarette smoking is the leading cause of preventable mortality in the U.S. Cessation interventions delivered through smartphone applications (apps) can reach large populations of individuals who smoke. Ecological Momentary Assessment (EMA), a feature often included in existing cessation apps, can be used to track behaviors and other important constructs and to inform Just-In-Time Interventions. However, the influence of EMA engagement on smoking cessation is unknown. Additionally, the implications of incentivizing the use of EMA for cessation outcomes is currently unknown. The National Cancer Institute’s publicly available smoking cessation app, quitSTART, includes a two-week voluntary EMA protocol (42 total EMA prompts), which provides an opportunity to explore the impact of EMA incentivization on smoking cessation.

Objective:

This study aimed to examine the influence of app-based EMA participation on smoking cessation for people who are incentivized to use EMA compared to those who are not incentivized (representing the current implementation of EMA within quitSTART).

Methods:

N=152 U.S. adults were recruited from online and text-message sources into a randomized controlled trial. All eligible participants were randomized to either non-incentivized EMA or incentivized EMA. Participants completed baseline, two- and four-week assessments. The primary outcome of interest was seven-day point prevalence abstinence measured at two and four weeks after app download. Average EMAs completed by arm was compared using a t-test. Firth logistic regression modeling was used to determine the association between arm and smoking abstinence at two and four weeks, adjusted for smoking frequency and concurrent use of other tobacco products.

Results:

The mean number of EMAs completed was 13.3 in the incentivized arm (range=0-40) and 4.7 (range=0-28) in the non-incentivized arm (p<.001). Cessation rates were 9.0% and 20.3% at 2-weeks (p=.062), and 17.5% and 36.6% at 4-weeks (p=.013) in the incentivized arm and non-incentivized arm, respectively. Arm was not associated with cessation in adjusted models (AOR, two-weeks: 0.60, 95% CI: 0.21-1.73, AOR four-weeks: 0.51, 95% CI: 0.22-1.19). Sensitivity analyses coding missing responses as smoking found that at four weeks, those in the incentivized arm were less likely to report abstinence (AOR: 0.41, 95% CI: 0.18-0.93).

Conclusions:

This study attempted to isolate and examine the effect of incentivizing EMA engagement on smoking cessation success for adults using a smartphone app to quit. While participants randomized to incentivization of EMA showed higher engagement with this feature, our findings suggest that there was no additional short-term cessation benefit from this engagement. Sensitivity analyses found a potential benefit for allowing autonomy over the use of app features, despite the ability of EMA completion to provide real-time tailored cessation support. Clinical Trial: clinical trials.gov identifier: NCT04623736