Table 3.
Factors associated with pharmacogenomic study participation: univariate model*
| Variable | OR (95% CI) | P |
|---|---|---|
| Site: CALGB vs CTSU | 2.08 (1.64 to 2.63) | <.001 |
| Self-reported race†: nonwhite vs white | 0.50 (0.43 to 0.57) | <.001 |
| Age‡ | 1.00 (0.97 to 1.03) | .97 |
| Sex: female vs male | 0.91 (0.76 to 1.10) | .33 |
| Rate of pharmacogenomic accrual§ | 1.00 (0.96 to 1.05) | .95 |
| Self-reported race by site | ||
| CALGB: nonwhite vs white | 0.43 (0.39 to 0.48) | <.001 |
| CTSU: nonwhite vs white | 0.51 (0.43 to 0.61) | <.001 |
* Generalized estimating equation model accounts for variability of patient participation among the separate clinical trials by use of study as a “cluster variable,” because patients are clustered within individual trials. Reported P values are two-sided. CI = confidence interval; OR = odds ratio.
† Nonwhite = African American, Asian, other (Native American, Pacific Islander, mixed race); white = Caucasian; persons with unknown data for race were excluded from this analysis (n = 8252).
‡ Age was analyzed as a continuous variable, and OR is reported for 10-year increments.
§ Rate of pharmacogenomics accrual calculated as the number of patients accrued to the pharmacogenomics study at each institution per year, during the time the institution was actively accruing patients to the study and is presented in increments of 10.