Table 3.

Concordance of rectal chlamydia and urethral chlamydia between men in all 473 partnerships in which both men were screened for urethral and rectal chlamydia on the same day

	Urethra negative	Urethra positive	Total	Urethral chlamydia positivity % (95% CI)
Rectum negative	884	16	900	1.8 (1.0 to 2.9)
Rectum positive	32	14	46	30.4 (17.7 to 45.8)
Total	916	30	946	3.2 (2.1 to 4.5)
Rectal chlamydia positivity % (95% CI)	3.5 (2.4 to 4.9)	46.7 (28.3 to 65.7)	4.9 (3.6 to 6.4)

(McNemar’s test p = 0.02)

Each man is represented twice: once as a urethra and once as a rectum