Variable | HIV(+), N=361 | HIV(−), N=9837 | p Value | RPR≧4, N=228 (2.24%) | RPR<4, N=9970 (97.76%) | p Value | IHA≧128, N=104 (1.02%) | IHA<128, N=10 094 (98.98%) | p Value | Chlamydia(+), N= 98 (4.68%) | Chlamydia(−), N=1996 (95.3%) | p Value | Gonorrhoea(+), N=14 (0.67%) | Gonorrhoea(−), N=2080 (99.3%) | p Value |
Male gender, n (%) | 350 (96.9) | 8599 (87.4) | <0.001 | 227 (99.6) | 8722 (87.5) | <0.001 | 101 (97.1) | 8848 (87.7) | 0.001 | 76 (77.6) | 1838 (92.1) | <0.001 | 12 (85.7) | 1902 (91.4) | 0.342 |
Age, mean (SD), years | 30.0 (7.0) | 28.4 (7.4) | <0.001 | 28.3 (6.7) | 28.4 (7.4) | 0.863 | 33.5 (7.5) | 28.4 (7.4) | <0.001 | 28.1 (6.8) | 28.8 (8.1) | 0.614 | 29.6 (6.8) | 28.1 (6.8) | 0.398 |
Education, higher than college, n (%) | 247 (68.4) | 7315 (74.5) | 0.01 | 162 (71.1) | 7400 (74.3) | 0.283 | 63 (60.6) | 7499 (74.1) | 0.002 | 69 (70.4) | 1582 (79.3) | 0.042 | 8 (57.1) | 1643 (79.0) | 0.090 |
MSM, n (%) | 333 (92.2) | 5591 (56.8) | <0.001 | 209 (91.7) | 5715 (57.3) | <0.001 | 94 (90.4) | 5830 (57.8) | <0.001 | 59 (60.2) | 1369 (68.6) | 0.095 | 10 (71.4) | 1429 (68.7) | >0.999 |
Injection drug use, n (%) | 5 (1.4) | 16 (0.2) | 0.001 | 2 (0.9) | 19 (0.2) | 0.79 | 1 (1.0) | 20 (0.2) | 0.194 | 0 (0) | 3 (0.2) | >0.999 | 0 (0) | 3 (0.1) | >0.999 |
Circumcision (male, N=9276), n (%) | 64 (20.2) | 1527 (17.1) | 0.609 | 38 (18.2) | 1553 (19.4) | 0.723 | 25 (27.5) | 1566 (19.3) | 0.061 | 20 (26.7) | 355 (19.9) | 0.185 | 3 (25.0) | 372 (20.2) | 0.717 |
Use of illicit non-injection recreational drugs, n (%) | 110 (30.5) | 725 (7.4) | <0.001 | 53 (23.2) | 782 (7.8) | <0.001 | 11 (10.6) | 824 (8.2) | 0.366 | 11 (11.2) | 188 (9.4) | 0.595 | 4 (28.6) | 195 (9.4) | 0.037 |
Having HIV-infected sexual partners, n (%) | 68 (18.8) | 783 (8.0) | <0.001 | 24 (10.6) | 827 (8.3) | 0.223 | 15 (14.4) | 836 (8.3) | 0.032 | 7 (7.1) | 170 (8.5) | 0.852 | 2 (14.3) | 175 (8.4) | 0.334 |
One-night stand, n (%) | 175 (48.5) | 3373 (34.3) | <0.001 | 124 (54.4) | 3424 (34.4) | <0.001 | 44 (42.3) | 3504 (34.7) | 0.119 | 39 (39.8) | 675 (33.9) | 0.231 | 9 (64.3) | 705 (33.9) | 0.023 |
Anal sex, n (%) | 266 (73.7) | 4217 (43.0) | <0.001 | 173 (76.2) | 4310 (43.3) | <0.001 | 71 (68.3) | 4412 (43.8) | <0.001 | 46 (47.4) | 991 (49.7) | 0.678 | 8 (57.1) | 1029 (49.6) | 0.604 |
Oral sex, n (%) | 277 (76.9) | 6749 (68.7) | 0.001 | 191 (84.1) | 6835 (68.6) | <0.001 | 77 (74.0) | 6949 (68.9) | 0.288 | 73 (76.0) | 1349 (67.6) | 0.093 | 13 (92.9) | 1409 (67.8) | 0.047 |
History of STIs, n (%) | 54 (21.8) | 595 (8.5) | <0.001 | 65 (42.5) | 584 (8.2) | <0.001 | 9 (11.5) | 640 (8.9) | 0.422 | 5 (18.5) | 72 (11.1) | 0.22 | 0 (0) | 77 (11.5) | >0.999 |
Oral-anal sex, n (%) | 113 (34.4) | 2010 (21.7) | <0.001 | 61 (28.8) | 2062 (22.0) | 0.024 | 46 (49.5) | 2077 (21.9) | <0.001 | 30 (30.6) | 488 (24.5) | 0.187 | 7 (50.0) | 511 (24.6) | 0.054 |
HIV (+), n (%) | – | – | – | 43 (18.9) | 318 (3.2) | <0.001 | 20 (19.2) | 341 (3.4) | <0.001 | 5 (5.1) | 68 (3.4) | 0.388 | 2 (14.3) | 71 (3.4) | 0.083 |
RPR≧4, n (%) | 43 (11.9) | 185 (1.9) | <0.001 | – | – | – | 11 (10.6) | 217 (2.1) | <0.001 | 2 (2.0) | 45 (2.3) | >0.999 | 2 (14.3) | 45 (2.2) | 0.038 |
IHA≧128, n (%) | 20 (5.5) | 84 (0.9) | <0.001 | 11 (4.8) | 93 (0.9) | <0.001 | – | – | – | 1 (1.0) | 22 (1.1) | >0.999 | 1 (7.1) | 22 (1.1) | 0.144 |
Chlamydia trachomatis infection, n (%) | 5 (6.8) | 93 (4.6) | 0.388 | 2 (4.3) | 96 (4.7) | >0.999 | 1 (4.3) | 97 (4.7) | >0.999 | – | – | – | 6 (42.9) | 92 (4.4) | <0.001 |
Neisseria gonorrhoeae infection, n (%) | 2 (2.7) | 12 (0.6) | 0.083 | 2 (4.3) | 12 (0.6) | 0.038 | 1 (4.3) | 13 (0.6) | 0.144 | 6 (6.1) | 8 (0.4) | <0.001 | – | – | – |
Having casual sexual partner, n (%) | 181 (54.8) | 4073 (44.1) | <0.001 | 119 (56.1) | 4135 (44.2) | 0.001 | 42 (44.7) | 4212 (44.5) | >0.999 | 43 (44.3) | 730 (36.6) | 0.132 | 8 (57.1) | 765 (36.8) | 0.163 |
Urethral symptoms, n (%) | 17 (5.1) | 561 (6.0) | 0.557 | 14 (6.6) | 564 (6.0) | 0.661 | 6 (6.4) | 572 (6.0) | 0.826 | 24 (24.5) | 116 (5.8) | <0.001 | 6 (42.9) | 134 (6.4) | <0.001 |
IHA, indirect haemagglutination; MSM, men who have sex with men; RPR, rapid plasma reagin; STI, sexually transmitted infection.