Influence of race, clinical, and other socio-demographic features on trial participation.

We assessed whether sociodemographic and clinical characteristics were determinants of clinical trial participation in the Women's Estrogen for Stroke Trial (WEST) by examining data collected on women with a WEST consent visit completed after June 1996. We found no differences in consent rates by education or ethnic group (32% of white women compared with 34% of black women). Conditions associated with the intervention, such as a history of hysterectomy or previous estrogen replacement use, were strongly associated with a woman's decision to participate in this clinical trial. In multivariate models, features independently associated with consent to participate were age (odds ratio [OR] 0.96, 95% confidence interval [CI] 0.94-0.97), hysterectomy (OR 1.78, 95% CI 1.27-2.50), no cognitive impairment (OR 1.70, 95% CI 1.10-2.63), history of volunteerism (OR 1.62, 95% CI 1.02-2.63), and previous estrogen use (RR 1.58, 95% CI 1.08-2.30).