African American smokers interested and eligible for a smoking cessation clinical trial: predictors of not returning...

Recruitment is often the rate-limiting step in conducting clinical trials among ethnic minorities. Little is known about participants who consent and enroll into a trial, but do not return for randomization. Why participants fail to return for randomization is largely unknown.

We compared 287 enrolled African American smokers who did not return for randomization, to the 500 who returned and were randomized to participate in a clinical trial for smoking cessation in African Americans. Analyses were conducted to identify variables associated with not returning for randomization.

Univariate comparisons found the nonrandomized group to be significantly different from those randomized. Logistic regression showed younger age, less readiness to quit, having been proactively recruited, lacking a regular source of health care, believing that they will be smoking in 6 months, less church attendance, and a lower literacy level to be jointly related with not returning for randomization.

African American participants who did not return for randomization into a clinical trial were different from those who did. Better understanding of these factors may allow researchers to target recruitment efforts resulting in enhanced accrual in clinical trials and increased efficiency.