Participation of African Americans in a smoking cessation trial: a quantitative and qualitative study.

African Americans (AAs) have been considered a hard to reach research population. In a clinical trial of bupropion for smoking cessation, failure to return for randomization was concerning during the initial phase of recruitment. There were three study goals: to review the research on clinical trial participation barriers, to use quantitative analyses to identify differences between randomized (n = 66) and non-randomized (n = 54) participants, and to use focus groups and interviews (2 groups and 2 interviews, 17 participants) to elicit participation barriers and suggestions for participation enhancement. Randomized participants were older (44.1 vs. 37.6; p = 0.0019), predominately female (81.8% vs. 63.0%; p = 0.0201), more likely to have some college (33.3% vs. 16.7%; p = 0.0380), and less likely to be employed full time (32.4% vs. 53.7%; p = 0.0347). Randomized participants reported higher motivation to quit smoking (8.3 vs. 7.3; p = 0.0083) and higher confidence to quit (8.2 vs. 7.3; p = 0.0357). A logistic regression model specified age, gender, and motivation to quit, as predictors of randomization. Focus groups identified transportation, lack of readiness to quit, inadequate reminders, and employment conflicts as barriers to participation. Knowledge of differences between those who return for enrollment and those who do not may be used to increase AA enrollment in clinical trials.