| | Unadjusted OR (95% CI) | value | Adjusted OR (95% CI) | value |
| Gender | | | | | Male | 1.17 (1.09, 1.25) | <.001 | 1.17 (1.09, 1.27) | <.001 | Females | 1.0 | | 1.0 |
| Age groups (years) | | | | | 16–24 | 1.0 | | 1.0 | | 25–34 | 2.00 (1.83, 2.18) | <.001 | 2.47 (2.19, 2.78) | <.001 | 35–44 | 2.32 (2.11, 2.54) | <.001 | 2.85 (2.50, 3.25) | <.001 | 45–54 | 2.65 (2.36, 2.97) | <.001 | 3.46 (2.97, 4.03) | <.001 | 55–64 | 2.93 (2.45, 3.51) | <.001 | 4.11 (3.30, 5.10) | <.001 | 65–82 | 2.80 (1.94, 4.05) | <.001 | 3.61 (2.35, 5.54) | <.001 | Education | | | | | 9–12th grade, no diploma | 1.0 | | 1.0 | | High school graduate | 1.35 (1.22, 1.51) | <.001 | 0.94 (0.83, 1.07) | .359 | Some college or tech | 1.24 (1.13, 1.35) | <.001 | 0.75 (0.67, 0.85) | <.001 | Bachelor degree | 1.67 (1.52, 1.83) | <.001 | 0.77 (0.67, 0.89) | <.001 | First-time donor? | | | | | Yes | 0.88 (0.82, 0.95) | <.001 | 1.30 (1.18, 1.42) | <.001 | No | 1.0 | | 1.0 |
| History of transfusion? | | | | | Yes | 1.18 (0.95, 1.47) | .134 | 0.88 (0.69, 1.11) | .276 | No | 1.0 | | 1.0 | | History of deferral? | | | | | Yes | 1.19 (1.07, 1.32) | .001 | 1.09 (0.96, 1.23) | .183 | No | 1.0 | | 1.0 |
| Donation site | | | | | Fixed site | 1.36 (1.22, 1.51) | <.001 | 1.20 (1.06, 1.35) | .005 | Mobile site | 1.0 | | 1.0 | |
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