Factors (measured at T1) | N response (%) | n positive for chlamydia | Positivity rate % (95% CI) | Univariate Cox regression PR (95% CI) | Multivariate Cox regression PR (95% CI)* |
---|---|---|---|---|---|
Total | 275 | 56 | 20.4 | ||
Gender | |||||
Male | 56 (20.4) | 15 | 26.8 (14.8 to 38.3) | 1.0 | nt |
Female | 219 (79.6) | 41 | 18.7 (13.5 to 23.9) | 0.7 (0.4 to 1.3) | |
Age (years) | |||||
16–19 | 81 (29.5) | 19 | 23.5 (14.0 to 32.9) | 0.8 (0.5 to 1.4) | nt |
20–23 | 194 (70.5) | 37 | 19.1 (13.5 to 24.6) | 1.0 | |
Ethnicity | |||||
Dutch | 246 (89.5) | 48 | 19.5 (14.5 to 24.5) | 0.7 (0.3 to 1.5) | nt |
Non-Dutch | 29 (10.5) | 8 | 27.6 (10.3 to 44.8) | 1.0 | |
Notified by partner | |||||
Yes | 10 (3.6) | 9 | 90.0 (67.4 to 112.6) | 5.1 (2.5 to 10.4) | 5.3 (2.4 to 11.5) |
No | 265 (96.4) | 47 | 17.7 (13.1 to 22.4) | 1.0 | |
STI-related symptoms† | |||||
Yes | 41 (15.1) | 22 | 53.7 (37.7 to 69.6) | 3.8 (2.2 to 6.4) | 3.2 (1.8 to 5.6) |
No | 231 (84.9) | 33 | 14.3 (9.7 to 18.8) | 1.0 | 1.0 |
Residence† | |||||
City | 157 (59.0) | 38 | 24.2 (17.4 to 31.0) | 1.6 (0.9 to 2.7) | 1.6 (0.9 to 2.9) |
Rural | 109 (41.0) | 17 | 15.6 (8.7 to 22.5) | 1.0 | 1.0 |
No. of partners <6 months | |||||
0–2 | 223 (81.1) | 35 | 15.7 (10.9 to 20.5) | 1.0 | 1.0 |
≥3 | 52 (18.9) | 21 | 40.4 (26.6 to 54.2) | 2.6 (1.5 to 4.4) | 1.5 (0.9 to 2.8) |
Condom use during the last sexual contact† | |||||
Yes | 61 (22.6) | 19 | 31.1 (19.2 to 43.1) | 1.8 (1.0 to 3.2) | 1.7 (0.9 to 3.1) |
No | 209 (77.4) | 36 | 17.2 (12.1 to 22.4) | 1.0 | 1.0 |
nt, not tested in multivariate model, since p>0.20 in univariate analysis.
In bold: significant (p<0.05); due to rounding to one decimal place, 1.0 is not always significant.
*Adjusted for notified by partner, STI symptoms, urbanisation, number of partners in <6 months and condom use during the last sex contact.
†Characteristic contains missings.
PR, prevalence ratio.