Table 1.
Characteristics of the Volunteers at Baseline
| Characteristic | 18–59 y (n = 397) |
≥ 60 y (n = 37) |
Total (n = 434) |
P Value |
|---|---|---|---|---|
| Age, mean ± standard deviation | 38.2 ± 9.7 | 64.0 ± 4.3 | 40.4 ± 11.8 | |
| Inoculation | .482 | |||
| Vaccine, n (%) | 245 (61.7) | 25 (67.6) | 270 (62.2) | |
| Placebo, n (%) | 152 (38.3) | 12 (32.4) | 164 (37.8) | |
| Sex | .039 | |||
| Female, n (%) | 251 (63.2) | 17 (45.9) | 268 (61.8) | |
| Male, n (%) | 146 (36.8) | 20 (54.1) | 166 (38.2) | |
| Ethnicity | .152 | |||
| White, n (%) | 370 (93.2) | 37 (100.0) | 407 (93.8) | |
| Other, n (%) | 27 (6.8) | 0 (0.0) | 27 (6.2) |
P values are for comparison between total numbers in each characteristic.