| Variable | Number of men (n = 397) |
| Age years (mean) | 34 (19–57) |
| Ethnicity | |
| White | 321 (80.9%) |
| Black | 14 (3.5%) |
| Asian | 14 (3.5%) |
| Other | 38 (9.6%) |
| Unknown | 10 (2.5%) |
| Site of chlamydia infection | |
| Urethral | 165/397 (41.6%) |
| Rectal | 247/397 (62.2%) |
| Urethral and rectal | 15/397 (3.8%) |