Table 3.

Multivariate analysis of demographic covariates for chlamydia infection and any STI in 729 female sex workers

	Chlamydia		Any STI
	aOR* (95% CI)	P	aOR (95% CI)	P
Age (years)		0·042		0·016
16–19	1		1
20–24	0·71 (0·37–1·33)		0·68 (0·37–1·23)
⩾25	0·39 (0·18–0·85)		0·37 (0·18–0·75)
Marital status
Ever married	1		1
Never married	0·76 (0·42–1·35)		0·66 (0·38–1·13)
Education
Elementary/none	1		1
Junior high or above	1·19 (0·68–2·10)		1·34 (0·78–2·29)
Monthly income (yuan†)		0·048		0·010
<3000	1		1
⩾3000	1·58 (1·00–2·50)		1·75 (1·14–2·67)
Origin				0·10
Zhenjiang/Shanghai	1		1
East China, other	2·00 (0·98–4·06)		2·53 (1·26–5·07)
Southwest/South	1·72 (0·83–3·55)		1·99 (0·97–4·06)
Central China	1·37 (0·63–3·01)		2·14 (1·02–4·50)
North	1·25 (0·45–3·41)		1·45 (0·55–3·85)

aOR, Adjusted odd ratio; CI, confidence interval; STI, sexually transmitted infection.

^*Adjusted for the remaining variables in the table.

^†1 Chinese yuan = ~$US 0·16.