Table 2.

Logistic analysis of factors associated with the risk of severe malaria

Factor	The number of cases, N(%)	Odds ratio (95% CI)
		Crude	P-value	Adjusted	P-value
Sex
Female	17(1.69)	reference		reference
Male	991(98.31)	0.138(0.047–0.407)	< 0.001	0.110(0.027–0.442)	0.002
Age (years),mean(SD)	41.28(9.33)	1.027(0.998–1.058)	0.070	1.049(1.015–1.083)	0.004
Occupation
Worker	902(89.48)	reference		reference
Waiter	77(7.64)	2.109(0.958–4.641)	0.064	2.698(1.054–6.906)	0.038
Other	29(2.88)	2.911(0.973–8.705)	0.056	1.746(0.459–6.649)	0.414
Duration of stay overseas (days)
≤ 30	34(3.37)	reference		reference
31–180	180(17.86)	0.885(0.281–2.786)	0.835	3.208(0.828–12.427)	0.092
181–365	237(23.51)	0.330(0.097–1.120)	0.075	1.150(0.280–4.733)	0.846
> 365	525(52.08)	0.328(0.106–1.013)	0.053	1.252(0.329–4.770)	0.742
Missing	32(3.17)	NA	NA	NA	NA
Time from onset to visit (days), median (IQR)	1(0,2)	1.052(1.007–1.098)	0.022	1.061(1.011–1.114)	0.016
Time from visit to diagnosis (days), median (IQR)	1(0,2)	1.084(1.032–1.139)	0.001	1.014(0.946–1.088)	0.690
The level of health facilities for initial medical visit
Private and village clinics	141(13.99)	reference		reference
Primary hospitals	97(9.62)	0.651(0.257–1.650)	0.366	0.966(0.350–2.671)	0.947
County-level hopsitals	297(29.46)	0.300(0.136–0.666)	0.003	0.769(0.299–1.979)	0.586
City-level hospitals	241(23.91)	0.482(0.228–1.020)	0.056	1.193(0.481–2.957)	0.703
Provincial hospitals	227(22.52)	0.398(0.179–0.884)	0.024	1.283(0.488–3.372)	0.613
Other	11(1.09)	NA	NA	NA	NA
The diagnosis result of first medical visit
Malaria	716(71.03)	reference		reference
Other diseases	292(28.97)	4.951(2.851–8.599)	< 0.001	5.167(2.535–10.533)	< 0.001
Previous malaria
No	385(38.19)	reference		reference
Yes	623(61.81)	0.271(0.155–0.476)	< 0.001	0.392(0.212–0.727)	0.003