Predictors of enrollment in a smoking cessation clinical trial after eligibility screening

Abstract

Purpose: A fraction of smokers considered eligible for pharmacotherapy treatment trials for nicotine dependence enrolled. Little is known about smokers not enrolling in a treatment trial or how these smokers differ from those who have enrolled.

Procedures: We screened 2257 individuals for a smoking cessation trial involving behavioral counseling and a novel medication.

Findings: Of those screened, 33% of callers were eligible for enrollment (N=753). Of those eligible for the trial, 37% attended the subsequent enrollment session (N=282). We compared the 282 attendees to the 471 smokers who were eligible for the trial but did not attend. Logistic regression indicated that African American smokers were about half as likely to enroll in the trial (odds ratio [OR], 0.55; 95% CI, 0.36-0.84); for every year increase in age, participants were 4% more likely to enroll (OR, 1.04; 95% CI, 1.02-1.06); and participants who were motivated to enroll in the trial for financial incentives were 42% less likely to enroll in the trial (OR, 0.58; 95% CI, 0.45-0.76).

Conclusions: These findings suggest the need to devise and test recruitment strategies directed toward African Americans and younger smokers to increase enrollment among eligible smokers to smoking cessation treatment trials.