Table 1. Demographic Characteristics and Other Risk Factors for Cases and Controls.
| Variables | Cases (% or SD) | Controls (% or SD) | P-value |
| Age ≥65 | 51(49.5%) | 93(45.1%) | 0.1 |
| Han Ethnicity | 63(61.2%) | 124(60.2%) | 1.0 |
| Educational Attainment | 1.0 | ||
| Lower than middle school | 74(71.9%) | 157(79.2%) | |
| Middle school and above | 29(28.1%) | 49(23.8%) | |
| Residency | 1.0 | ||
| Rural | 77(74.8%) | 159(77.2%) | |
| Suburban | 26(25.2%) | 47(22.8%) | |
| Tobacco and Alcohol Use | 0.7 | ||
| Tobacco/alcohol/tobacco & alcohol | 81(78.6%) | 158(76.7%) | |
| None | 22(21.4%) | 48(23.3%) | |
| Condom use | 0.01 | ||
| Never use | 69(67.0%) | 115(55.8%) | |
| Use sometimes | 34(33.0%) | 91(44.2%) | |
| Years of purchasing sex | 7.4±4.9 | 7.2±4.7 | 0.7 |
| Aphrodisiac Use | 45(43.7%) | 45(21.8%) | 0.03 |
| Erection dysfunction | 13(12.6%) | 32(15.5%) | 0.2 |
| Having a stable partner | 59(57.3%) | 142(68.9%) | 0.00 |
| Frequency of purchasing commercial sexduring last month | 0.7 | ||
| < = 1 | 76(74.0%) | 148(71.8%) | |
| >1 | 27(26.0%) | 58(28.2%) | |
| Awareness of HIV/AIDS | 61(59.2%) | 136(66.0%) | 0.4 |