Predictors of attrition in a randomized controlled trial of an electronic nicotine delivery system among people interested in cigarette smoking reduction. Contemp Clin Trials 2024 Oct;145:107662
Date
08/15/2024Pubmed ID
39142511Pubmed Central ID
PMC11492368DOI
10.1016/j.cct.2024.107662Scopus ID
2-s2.0-85202456052 (requires institutional sign-in at Scopus site)Abstract
BACKGROUND: Mitigating attrition is a key component to reduce selection bias in longitudinal randomized controlled trials (RCTs). Few studies of electronic nicotine delivery systems (ENDS) allow for the examination of long-term retention. This analysis explores the relationship between attrition, baseline measures, and condition assigned for a RCT involving ENDS differing in nicotine delivery over a 24-week intervention period.
METHODS: Participants (N = 520) who smoked ≥10 cigarettes per day [CPD] for ≥1 year and reported interest in reducing but not quitting were randomized to 1 of 4 conditions: an ENDS containing 0, 8, or 36 mg/ml liquid nicotine (administered double-blind) or a cigarette-shaped plastic tube. Cox proportional hazards regression models were fit to examine attrition over time and predictors of attrition including baseline characteristics and condition. A stepwise approach was used to determine the final model; alpha was set at 0.05.
RESULTS: Attrition did not differ significantly by condition (223/520), and most (69%) were lost-to-follow-up. Only age, education level, and household income were significantly predictive of attrition. For every additional year of age, attrition risk fell by 3%. Holding a bachelor's degree or higher was associated with reduced attrition risk. Those with the lowest income (<$10 K) were more likely to be withdrawn compared to those earning $10 K-39 K, and those with the highest income ($100 K+) were more likely to be withdrawn compared with the latter bracket and those earning $70-99 K.
CONCLUSION: ENDS nicotine content did not drive differential attrition in this trial, and targeted retention efforts are needed for specific subgroups. Trial Registration #: NCT02342795.
Author List
Cobb CO, Budd S, Maldonado G, Imran R, Foulds J, Yingst J, Yen MS, Kang L, Sun S, Hall PB, Chowdhury N, Cohen JE, Randomized Control Trial Methods Workgroup of the Center for the Study of Tobacco Products: Member ListAuthor
Alexa Anderson PhD Associate Professor in the Nursing department at University of Wisconsin - MilwaukeeMESH terms used to index this publication - Major topics in bold
AdultAge Factors
Cigarette Smoking
Double-Blind Method
Educational Status
Electronic Nicotine Delivery Systems
Female
Humans
Income
Lost to Follow-Up
Male
Middle Aged
Nicotine
Proportional Hazards Models
Smoking Cessation
Smoking Reduction
Young Adult
