Table 1.
Demographic Characteristics and Risk Behaviors at Baseline in the Per-Protocol Cohort.*
| Variable | HSV-Vaccine Group (N = 3798) | Control Group (N = 3076) | All Subjects (N = 6874) |
|---|---|---|---|
| number (percent) | |||
| Demographic characteristics | |||
| Age | |||
| 18–22 yr | 2141 (56) | 1703 (55) | 3844 (56) |
| 23–26 yr | 1115 (29) | 974 (32) | 2089 (30) |
| 27–30 yr | 542 (14) | 399 (13) | 941 (14) |
| Race or ethnic group† | |||
| White | 3040 (80) | 2492 (81) | 5532 (80) |
| Black | 389 (10) | 301 (10) | 690 (10) |
| Asian | 140 (4) | 116 (4) | 256 (4) |
| Other | 229 (6) | 167 (5) | 396 (6) |
| Risk behaviors‡ | |||
| Provided at least 1 response on risk-factor questionnaire | 3615 (95) | 2934 (95) | 6549 (95) |
| Reported ever having sex | 3245 (85) | 2645 (86) | 5890 (86) |
| Age 16–18 yr when first had sex | 1749 (46) | 1420 (46) | 3169 (46) |
| More than 1 lifetime sexual partner | 2701 (71) | 2231 (73) | 4932 (72) |
| Reported using condoms | 2491 (66) | 1959 (64) | 4450 (65) |
*
No significant differences were observed between treatment groups (P>0.05 for all comparisons). HSV denotes herpes simplex virus.
†
Race or ethnic group was determined by self-report. Other includes American Indian, Alaskan Native, Native Hawaiian, and Pacific Islander. Data on ethnic group are reported in the Supplementary Appendix.
‡
Risk-behavior questions were required only for subjects who responded “yes” to “ever had sex.” The most frequently reported responses are presented. Detailed summaries of risk behaviors are provided in the Supplementary Appendix.