Table 3.

Multivariable Cox proportional hazards analysis of risk of new infection during the 1984–1992 Msambweni school-based schistosomiasis control program: multiply-adjusted risk-ratios according to subject characteristic^*

Characteristic	RR	95% CI	P
Age category, years
12–20	1.00	Reference
5–11	1.80	1.38–2.33	< 0.0001
Village of residence
Vingujini	1.00	Reference
Bomani	1.45	1.05–1.99	0.02
Mwaembe	1.49	1.04–2.13	0.02
Sawa Sawa	1.65	1.11–2.44	0.01
Vindungeni	4.66	2.49–8.84	< 0.0001
Kisimachande	2.92	2.05–4.16	< 0.0001
Nganja	4.51	2.69–7.53	< 0.0001
Milalani	5.28	3.55–7.74	< 0.0001
Hematuria at entry
None	1.00	Reference
Trace	1.80	0.74–4.39	0.21
1+	2.82	1.97–4.04	< 0.0001
2+	1.97	0.92–4.20	0.09
3+	2.61	1.07–6.35	0.03

^*RR = relative risk; CI = confidence interval.