Table 4 Univariate logistic regression model showing the factors associated with rectal chlamydia infection
VariableTotal (n = 397)Rectal (n = 247)Relative risk (95% CI)p Value
Age (years)
    ⩽279966 (66.68)1.35 (0.75 to 2.42)0.4902
    28–3211573 (63.48)1.12 (0.64 to 1.95)
    33–388649 (56.98)0.85 (0.47 to 1.54)
    >389759 (60.82)1
Ethnicity
    Unknown106 (60.00)0.87 (0.24 to 3.15)0.8085
    Other6639 (59.09)0.84 (0.49 to 1.44)
    White321202 (62.93)1
Rectal microscopy
    Negative304194 (63.82)1
    Positive7450 (67.57)1.16 (0.68 to 2.00)0.341
    Missing*193 (15.79)
Urethral chlamydia
    Negative232230 (99.14)1
    Positive16517 (10.30)0.00 (0.00 to 0.00)<0.0001
Gonorrhoea (all sites)†
    Negative337204 (60.53)1
    Positive6043 (71.67)1.63 (0.89 to 2.98)0.1043
Rectal gonorrhoea
    Negative3602141
    Positive37335.37 (1.86 to 15.51)0.0002
Syphilis
    Negative382237 (62.04)1
    Positive1510 (66.67)1.21 (0.41 to 3.61)0.7301
Warts
    Negative365221 (60.55)1
    Positive3226 (81.25)2.79 (1.12 to 6.95)0.0164
HIV
    Negative273153 (56.04)1
    Positive12494 (75.81)2.53 (1.56 to 4.08)<0.001
  • *Missing, microscopy was not performed.

  • †All cases of gonorrhoea. Some men had infection at more than one site.