| Full Cohort | Vaccinated | Unvaccinated |  | Female | Male |  | |||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Variable | N | Value | N | Value | N | Value | p-valuea | N | Value | N | Value | p-valuea |
Age | 241 | 18.9 (1.0) | 158 | 18.8 (1.0) | 59 | 19.1 (1.0) | 0.09 | 168 | 18.8 (1.0) | 73 | 19.0 (1.1) | 0.17 |
Female | 241 | 70% (168) | 158 | 74% (117) | 59 | 66% (39) | 0.25 | 168 | 100% (168) | 73 | 0% (0) | – |
Race | 241 |  | 158 |  | 59 |  | – | 168 |  | 73 |  | – |
 White |  | 54% (131) |  | 56% (88) |  | 61% (36) |  |  | 56% (94) |  | 52% (37) |  |
 Asian |  | 31% (74) |  | 30% (47) |  | 24% (14) |  |  | 29% (49) |  | 35% (25) |  |
 Black |  | 6% (14) |  | 4% (7) |  | 8% (5) |  |  | 5% (9) |  | 7% (5) |  |
 Other/multiracial |  | 8% (20) |  | 9% (14) |  | 7% (4) |  |  | 10% (16) |  | 6% (4) |  |
Vaccinated | 217 | 73% (158) | 158 | 100% (153) | 59 | 0% (0) | – | 156 | 75% (117) | 61 | 67% (41) | 0.25 |
Age at first vaccine dose | – | – | 102 | 15.5 (2.4) | – | – | – | 79 | 15.0 (2.5) | 22 | 16.7 (1.6) | <0.001 |
Current smoker | 231 | 1% (2) | 158 | 1% (1) | 59 | 2% (1) | – | 168 | 0% (0) | 73 | 3% (2) | – |
Alcohol: current user | 231 | 65% (157) | 158 | 68% (104) | 59 | 63% (35) | 0.49 | 168 | 65% (109) | 73 | 66% (48) | 0.90 |
Alcohol: ever binge drinkerb | 231 | 15% (37) | 158 | 16% (25) | 59 | 15% (9) | 0.92 | 168 | 11% (19) | 73 | 25% (18) | 0.01 |
Marijuana: ever user | 231 | 38% (91) | 158 | 37% (58) | 59 | 41% (24) | 0.59 | 168 | 36% (60) | 73 | 42% (31) | 0.32 |
Has had any sex | 231 | 63% (151) | 158 | 64% (101) | 59 | 61% (36) | 0.69 | 168 | 62% (104) | 73 | 64% (47) | 0.71 |
If has had sex, has had | ||||||||||||
 Vaginal | 151 | 77% (116) | 101 | 77% (78) | 36 | 75% (27) | 0.79 | 104 | 78% (81) | 47 | 74% (35) | 0.70 |
 Oral | 151 | 96% (145) | 101 | 97% (93) | 36 | 94% (31) | – | 104 | 97% (101) | 47 | 94% (44) | – |
 Anal | 151 | 20% (30) | 101 | 21% (21) | 36 | 22% (8) | 0.86 | 104 | 17% (18) | 47 | 26% (12) | 0.24 |
Lifetime number of sexual partners | ||||||||||||
 Any | 241 | 2.2 (3.7) | 158 | 2.7 (4.2) | 59 | 1.9 (2.7) | 0.15 | 168 | 2.1 (3.2) | 73 | 2.8 (4.6) | 0.24 |
 Vaginal sex | 241 | 1.6 (3.1) | 158 | 1.9 (3.5) | 59 | 1.2 (2.3) | 0.09 | 168 | 1.7 (2.9) | 73 | 1.4 (3.6) | 0.58 |
 Oral sex | 241 | 2.3 (3.6) | 158 | 2.7 (4.1) | 59 | 1.8 (2.7) | 0.09 | 168 | 2.1 (3.0) | 73 | 2.7 (4.7) | 0.34 |
 Anal sex | 241 | 0.2 (0.8) | 158 | 0.3 (0.8) | 59 | 0.2 (0.6) | 0.64 | 168 | 0.1 (0.5) | 73 | 0.4 (1.2) | 0.08 |
 Age at sexual debut | 150 | 16.6 (1.7) | 101 | 16.5 (1.7) | 36 | 16.9 (1.8) | 0.18 | 104 | 16.7 (1.6) | 46 | 16.5 (1.9) | 0.58 |
 Uses protection during vaginal sex | 114 |  | 78 |  | 26 |  | – | 81 |  | 33 |  | – |
 Always |  | 47% (54) |  | 41% (32) |  | 62% (16) |  |  | 46% (37) |  | 52% (17) |  |
 Most of the time |  | 32% (37) |  | 37% (29) |  | 23% (6) |  |  | 33% (27) |  | 30% (10) |  |
 Sometimes |  | 9% (10) |  | 8% (6) |  | 8% (2) |  |  | 11% (9) |  | 2% (1) |  |
 Rarely |  | 6% (7) |  | 9% (7) |  | 0% (0) |  |  | 5% (4) |  | 9% (3) |  |
 Never |  | 5% (6) |  | 5% (4) |  | 8% (2) |  |  | 5% (4) |  | 6% (2) |  |
 Uses protection during oral sex | 139 |  | 96 |  | 31 |  | – | 96 |  | 43 |  | – |
 Always |  | 1% (1) |  | 1% (1) |  | 0% (0) |  |  | 1% (1) |  | 0% (0) |  |
 Most of the time |  | 0% (0) |  | 0% (0) |  | 0% (0) |  |  | 0% (0) |  | 0% (0) |  |
 Sometimes |  | 4% (5) |  | 4% (4) |  | 3% (1) |  |  | 4% (4) |  | 2% (1) |  |
 Rarely |  | 8% (11) |  | 9% (10) |  | 0% (0) |  |  | 10% (10) |  | 2% (1) |  |
 Never |  | 88% (122) |  | 84% (81) |  | 97% (30) |  |  | 84% (81) |  | 95% (41) |  |
 Uses protection during anal sex | 30 |  | 21 |  | 8 |  | – | 18 |  | 12 |  | – |
 Always |  | 33% (10) |  | 29% (6) |  | 50% (4) |  |  | 28% (5) |  | 42% (5) |  |
 Most of the time |  | 17% (5) |  | 14% (3) |  | 13% (1) |  |  | 17% (3) |  | 17% (2) |  |
 Sometimes |  | 7% (2) |  | 10% (2) |  | 0% (0) |  |  | 11% (2) |  | 0% (0) |  |
 Rarely |  | 3% (1) |  | 5% (1) |  | 0% (0) |  |  | 0% (0) |  | 8% (1) |  |
 Never |  | 40% (12) |  | 43% (9) |  | 38% (3) |  |  | 44% (8) |  | 33% (4) |  |