For each study, we calculated an odds ratio (OR) and the associated 95% confidence interval (CI) using non-Hispanic whites as the reference group. The OR specifies, for each study, whether the reported minority group was more or less likely to consent to enrollment than non-Hispanic whites. An OR greater than one indicates that the minority group was more likely to consent than non-Hispanic whites; an OR of less than one indicates that the minority group was less likely to consent. A DerSimonian–Laird random effects model was used to estimate the summary OR and 95% CI for each type of study (i.e., non-intervention studies, clinical intervention studies, and surgical intervention studies), again using non-Hispanic whites as the reference group [32].
