Skip to main content
. 2017 Jul 17;16:288. doi: 10.1186/s12936-017-1938-1

Table 4.

Relative rate ratios of Anopheles per house, according to multi-covariate geostatistical Poisson regression models

Variable (n) Relative rate ratio (95% CI)
An. arabiensis An. gambiae s.s. An. funestus
Females Males Females Males Females Males
Habitat index a
1 1.00 1.00 1.00 1.00 1.00 1.00
2 0.85 (0.79, 0.93) 0.98 (0.92, 1.04) 0.69 (0.65, 0.72) 1.11 (1.06, 1.15) 2.01 (1.49, 2.72) 1.40 (1.27, 1.53)
3 1.79 (1.54, 2.08) 0.96 (0.90, 1.04) 0.53 (0.50, 0.57) 1.13 (1.08, 1.18) 1.23 (0.85, 1.76) 4.25 (3.50, 5.16)
4 2.24 (1.89, 2.65) 1.75 (1.62, 1.90) 1.38 (1.26, 1.51) 1.35 (1.27, 1.42) 2.30 (1.57, 3.37) 4.66 (3.78, 5.74)
LLIN use
None (130) 1.00 1.00 1.00 1.00 1.00 1.00
Some (81) 0.84 (0.82, 0.86) 1.97 (1.91, 2.04) 0.87 (0.85, 0.89) 0.88 (0.87, 0.90) 0.38 (0.37, 0.40) 0.91 (0.88, 0.94)
All (314) 0.49 (0.48, 0.50) 0.50 (0.48, 0.51) 0.39 (0.39, 0.40) 0.82 (0.81, 0.83) 0.60 (0.58, 0.61) 1.01 (0.99, 1.03)
Cooked
No (342) 1.00 1.00 1.00 1.00 1.00 1.00
Yes (183) 0.26 (0.26, 0.27) 0.32 (0.31, 0.33) 0.47 (0.47, 0.48) 0.37 (0.36, 0.37) 0.57 (0.56, 0.59) 0.42 (0.42, 0.43)
Cattle
No (166) 1.00 1.00 1.00 1.00 1.00 1.00
Yes (359) 2.39 (2.29, 2.50) 2.45 (2.34, 2.58) 2.76 (2.66, 2.85) 1.39 (1.34, 1.43) 0.88 (0.83, 0.94) 0.69 (0.66, 0.73)
Roof
Thatch (161) 1.00 1.00 1.00 1.00 1.00 1.00
Iron (364) 1.25 (1.23, 1.28) 0.77 (0.75, 0.78) 1.21 (1.19, 1.23) 0.77 (0.76, 0.78) 0.63 (0.62, 0.65) 0.46 (0.45, 0.47)
Wall
Mud (280) 1.00 1.00 1.00 1.00 1.00 1.00
Plastered (109) 0.80 (0.78, 0.82) 0.52 (0.51, 0.53) 0.80 (0.79, 0.82) 1.26 (1.24, 1.27) 1.67 (1.62, 1.73) 1.36 (1.33, 1.40)
Other (136) 0.72 (0.70, 0.74) 0.38 (0.37, 0.39) 1.15 (1.13, 1.17) 0.82 (0.81, 0.83) 0.66 (0.63, 0.68) 1.04 (1.01, 1.07)
No. people
(Mean = 3) 0.87 (0.86, 0.87) 0.72 (0.71, 0.72) 1.10 (1.10, 1.11) 1.06 (1.06, 1.06) 1.15 (1.14, 1.16) 0.90 (0.89, 0.90)
Geostatistical parameters
σ 2 0.27 (0.19, 0.38) 0.49 (0.32, 0.76) 0.14 (0.10, 0.19) 0.15 (0.10, 0.22) 1.27 (0.74, 2.20) 0.75 (0.45, 1.25)
φ 0.56 (0.38, 0.83) 0.84 (0.54, 1.31) 0.47 (0.33, 0.67) 0.83 (0.54, 1.26) 1.35 (0.77, 2.37) 1.21 (0.72, 2.05)

LLIN long-lasting impregnated nets. LLIN use, whether none, some or all of the residents used a LLIN the previous night; Cooked, whether residents cooked in the house the previous night; Cattle, whether cattle were present near the house the previous night; Roof, the main material of the roof; Wall, the main material of the walls; No. people, the number of people sleeping in the house the previous night; σ 2, variance parameter of the estimated spatial correlation; φ, scale parameter of the estimated spatial correlation

aAll analyses were done with larval habitat indices as continuous variables, but they are presented here as factors (grouped by quartiles within each habitat index) for a more intuitive interpretation of the effect on the relative rate ratio. The habitat index used for each species and sex is listed in Table 3. A higher value for habitat index indicates a house is more likely to be closer to more larval habitats