Table 2.

Characteristics of the study population.

Variable	Number of subjects (percent)
Overall	738
Age at enrollment
11–13	219(30)
14–15	196(27)
16–17	205(28)
18–19	118(16)
Gender
Male	396(54)
Female	342(46)
Race
White, non-Hispanic	672(91)
Other	66(9)
Age at first rubella vaccination
≤14 months	91(12)
15 months	394(53)
16–17 months	128(17)
≥18 months	125(17)
Age at second rubella vaccination
≤5 years	209(28)
6–10 years	113(15)
11 years	129(17)
≥12 years	287(39)