Table 3. Logistic regression analysis of the risk factors of Schistosoma haematobium infection.
Model 0 gives the univariate results and Model 1 includes all variables in the model. In Model 2, piped water coverage in the immediate community surrounding each participant has been substituted with household-level piped water covariate.
| Model 0: Univariate | Model 1: Community coverage | Model 2: Household access | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Covariate | aOR | (95% CI) | P-value | aOR | (95% CI) | P-value | aOR | (95% CI) | P-value |
| Community piped water quintiles (vs Lowest)† | |||||||||
| 2 | 0.77 | (0.34, 1.75) | 0.529 | 0.39‡ | (0.23, 0.66) | <0.001 | |||
| 3 | 0.57 | (0.22, 1.50) | 0.250 | 0.30 | (0.15, 0.59) | <0.001 | |||
| 4 | 0.27 | (0.10, 0.71) | 0.009 | 0.16 | (0.08, 0.33) | <0.001 | |||
| 5 | 0.41 | (0.17, 0.99) | 0.048 | 0.12 | (0.06, 0.26) | <0.001 | |||
| Household access to water (vs No) | |||||||||
| Yes | 0.96 | (0.56, 1.64) | 0.870 | 0.54 | (0.33, 0.89) | 0.017 | |||
| Gender (vs Female) | |||||||||
| Male | 2.24 | (1.64, 3.08) | <0.001 | 2.62 | (1.92, 3.59) | <0.001 | 2.41 | (1.77, 3.28) | <0.001 |
| Age testing | |||||||||
| Per unit | 1.19 | (1.07, 1.31) | 0.001 | 1.21 | (1.08, 1.36) | 0.001 | 1.18 | (1.06, 1.31) | 0.002 |
| Grade (vs Grade 5) | |||||||||
| Grade 6 | 0.86 | (0.45, 1.66) | 0.648 | 0.76 | (0.51, 1.11) | 0.149 | 0.77 | (0.47, 1.28) | 0.310 |
| Praziquantel in last 12 months (vs No) | |||||||||
| Yes | 2.18 | (1.05, 4.52) | 0.038 | 1.27 | (0.60, 2.71) | 0.529 | 1.48 | (0.69, 3.16) | 0.307 |
| Altitude Class (vs < 50) | |||||||||
| 50–100 | 0.58 | (0.27, 1.22) | 0.147 | 0.47 | (0.23, 0.96) | 0.039 | 0.50 | (0.23, 1.09) | 0.081 |
| 100–150 | 0.23 | (0.09, 0.60) | 0.003 | 0.20 | (0.09, 0.43) | <0.001 | 0.20 | (0.08, 0.51) | 0.001 |
| 150–200 | 0.13 | (0.04, 0.39) | <0.001 | 0.09 | (0.03, 0.25) | <0.001 | 0.11 | (0.04, 0.33) | <0.001 |
| >200 | 0.14 | (0.04, 0.51) | 0.004 | 0.08 | (0.03, 0.29) | <0.001 | 0.12 | (0.03, 0.44) | 0.002 |
| Landcover class (vs Sparse Shrubland) | |||||||||
| Closed Shrubland | 2.26 | (1.55, 3.28) | <0.001 | 1.56 | (1.05, 2.31) | 0.030 | 2.41 | (1.63, 3.58) | <0.001 |
| Open Shrubland | 1.00 | (0.70, 1.44) | 0.989 | 1.03 | (0.72, 1.47) | 0.863 | 1.44 | (0.96, 2.17) | 0.079 |
| Thickett | 2.71 | (1.28, 5.75) | 0.010 | 1.75 | (0.82, 3.73) | 0.145 | 2.52 | (1.23, 5.18) | 0.012 |
| Slope (square root) | |||||||||
| per unit | 0.98 | (0.83, 1.16) | 0.818 | 1.02 | (0.89, 1.16) | 0.794 | 0.91 | (0.79, 1.04) | 0.159 |
| Distance to water body (vs < 1 km) | |||||||||
| 1–2 km | 1.08 | (0.74, 1.58) | 0.667 | 0.78 | (0.56, 1.08) | 0.131 | 0.99 | (0.69, 1.41) | 0.946 |
| 2–3 km | 0.97 | (0.54, 1.75) | 0.928 | 0.72 | (0.47, 1.12) | 0.143 | 1.04 | (0.62, 1.77) | 0.874 |
| >3 km | 0.41 | (0.23, 0.74) | 0.003 | 0.25 | (0.12, 0.49) | <0.001 | 0.44 | (0.24, 0.79) | 0.007 |
| Toilet in household (vs No) | |||||||||
| Yes | 1.24 | (0.90, 1.72) | 0.186 | 1.24 | (0.87, 1.76) | 0.229 | 1.20 | (0.84, 1.72) | 0.319 |
| Household assets quintile (vs Poorest) | |||||||||
| 2 | 0.74 | (0.50, 1.09) | 0.123 | 0.88 | (0.60, 1.27) | 0.480 | 0.87 | (0.61, 1.25) | 0.459 |
| 3 | 0.73 | (0.49, 1.09) | 0.127 | 0.78 | (0.51, 1.18) | 0.235 | 0.75 | (0.48, 1.16) | 0.186 |
| 4 | 0.69 | (0.42, 1.14) | 0.143 | 0.81 | (0.47, 1.40) | 0.450 | 0.67 | (0.40, 1.11) | 0.118 |
| 5 | 0.72 | (0.41, 1.24) | 0.228 | 0.80 | (0.48, 1.34) | 0.389 | 0.62 | (0.36, 1.05) | 0.075 |
| Missing | 0.69 | (0.39, 1.21) | 0.194 | 0.84 | (0.40, 1.80) | 0.658 | 0.64 | (0.29, 1.40) | 0.258 |
† Computes the proportion of households having access to piped-water in the unique community surrounding each participant in the study (Figure 3). The Quintile (Q) ranges (min–max) are: Q1: 0–36; Q2: 37–59; Q3: 60–75; Q4: 76–92; Q5: 93–100, ‡ Corresponding values for a model in which community-level piped-water coverage is used as a continuous variable: a 1% increase in the coverage of piped-water in the surrounding community, was independently associated with a 2.5% decrease in the odds of a Schistosoma haematobium infection (aHR=0.975; 95% CI: 0.966, 0.985; p-value<0.001).