The risks of malaria infection in Kenya in 2009

BMC Infectious Diseases

Table 2 Results of univariate and multivariate analysis of the ecological and climatic covariates (SI 1) against Kenya PfPR_2-10 data of sample size ≥50 individuals.

	PfPR_2-10
	Number of survey locations	Mean (median) PfPR_2-10, Chi² (P-value)	Univariate regression*: Odds Ratio (95% CI), P-value	Multivariate regression*: Odds Ratio (95% CI), P-value
Categorical covariates
Urban
Rural	1636	27.6 (21.9)	Ref	Ref
Urban	458	15.4 (11.9)	0.48 (0.34, 0.66), <0.001	0.50 (0.36, 0.70), <0.001
		3300, <0.001
Maximum temperature (Degrees Celsius)
≤25	214	7.7 (2.3)	0.20 (0.10, 0.41), <0.001	0.25 (0.12, 0.52), <0.001
25-30	1628	29.8 (25.9)	Ref	Ref
>30	252	16.2 (9.2)	0.46 (0.35, 0.60), <0.001	0.61 (0.44, 0.85), 0.003
		4700.0, <0.001
Minimum temperature (Degrees Celsius)
<16	928	23.5 (17.1)	0.81 (0.66, 0.97), <0.036
≥16	1166	27.6 (21.9)	Ref
		754.7, <0.001
Sets of 3 consecutive months in an average year with precipitation >60 mm
0	1398	13.7 (9.0)	0.37 (0.26, 0.51), <0.001	0.53 (0.35, 0.83), 0.005
1-3	333	19.6 (12.4)	0.56 (0.42, 0.74), <0.001	0.63 (0.46, 0.85), 0.003
>3	363	30.3 (26.1)	Ref	Ref
		8200.0, <0.001
Enhanced vegetation index
> 0.3	1534	16.9 (11.3)	Ref	Ref
≤0.3	560	29.0 (24.4)	0.50 (0.39, 0.64), <0.001	0.78 (0.57, 1.06), 0.114
		3300.1, <0.001
Altitude (m)
0-500	689	22.2 (13.0)	0.59 (0.47, 0.74), <0.001
>500-1500	860	32.6 (29.1)	Ref
>1500	545	19.4 (13.0)	0.50 (0.39, 0.64), <0.001
		4100.2, <0.001
Distance (km) to main water bodies
≤12 mean distance	1306	28.6 (23.5)	Ref
>12 mean distance	788	21.1 (14.5)	0.67 (0.54, 0.82), <0.001	0.62(0.49, 0.77), <0.001
		3300, <0.001

*The category with the highest median PfPR_2-10 is used as the reference class. Therefore the odds ratios are expected to be below 1.00 for all covariates.

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