Table 3.
Multilevel logistic regression results on the joint effect of urbanicity and type of household cooking fuel on childhood anaemia
| Variables | Model 0 | Model I | Model II | Model III | Model IV | ||||
| aOR | 95% CI | aOR | 95% CI | aOR | 95% CI | aOR | 95% CI | ||
| Fixed effects | |||||||||
| Urbanicity-type of cooking fuel | |||||||||
| Clean-urban | 1 | 1 | 1 | 1 | |||||
| Unclean-urban | 1.350*** | 1.286 to 1.418 | 1.229*** | 1.145 to 1.320 | 1.206*** | 1.122 to 1.297 | 1.063 | 0.987 to 1.146 | |
| Unclean-rural | 1.673*** | 1.600 to 1.750 | 1.211*** | 1.129 to 1.299 | 1.115** | 1.032 to 1.205 | 1.120** | 1.033 to 1.214 | |
| Clean-rural | 1.273*** | 1.144 to 1.416 | 1.317*** | 1.136 to 1.526 | 1.239** | 1.067 to 1.438 | 1.256** | 1.080 to 1.460 | |
| Child age | |||||||||
| 0 | 1 | ||||||||
| 1 | 0.803*** | 0.762 to 0.847 | 0.804*** | 0.762 to 0.847 | 0.799*** | 0.758 to 0.844 | |||
| 2 | 0.498*** | 0.471 to 0.362 | 0.500*** | 0.473 to 0.528 | 0.493*** | 0.466 to 0.521 | |||
| 3 | 0.341*** | 0.321 to 0.362 | 0.345*** | 0.325 to 0.367 | 0.342*** | 0.322 to 0.364 | |||
| 4 | 0.261*** | 0.244 to 0.279 | 0.265*** | 0.247 to 0.284 | 0.264*** | 0.247 to 0.283 | |||
| Sex of child | |||||||||
| Male | 1 | 1 | 1 | ||||||
| Female | 0.862*** | 0.834 to 0.891 | 0.861*** | 0.833 to 0.890 | 0.857*** | 0.829 to 0.887 | |||
| Birth order | |||||||||
| 1 | 1 | 1 | 1 | ||||||
| 2 | 1.152*** | 1.092 to 1.216 | 1.124*** | 1.065 to 1.186 | 1.121*** | 1.061 to 1.184 | |||
| 3 and above | 1.397*** | 1.302 to 1.498 | 1.258*** | 1.170 to 1.353 | 1.269*** | 1.179 to 1.367 | |||
| Perceived birth size | |||||||||
| Larger than average | 1 | 1 | 1 | ||||||
| Average | 1.004 | 0.968 to 1.041 | 1.015 | 0.978 to 1.053 | 1.052** | 1.014 to 1.093 | |||
| smaller than average | 1.026 | 0.975 to 1.08 | 1.026 | 0.975 to 1.080 | 1.075** | 1.020 to 1.132 | |||
| Don't know | 1.184* | 1.009 to 1.39 | 1.178* | 1.003 to 1.384 | 1.129 | 0.960 to 1.328 | |||
| Age of mother | |||||||||
| 15–19 | 1 | 1 | 1 | ||||||
| 20–24 | 0.802*** | 0.735 to 0.875 | 0.834*** | 0.763 to 0.910 | 0.869*** | 0.795 to 0.950 | |||
| 25–29 | 0.658*** | 0.600 to 0.722 | 0.689*** | 0.628 to 0.756 | 0.733*** | 0.667 to 0.806 | |||
| 30–34 | 0.586*** | 0.532 to 0.647 | 0.608*** | 0.550 to 0.671 | 0.667*** | 0.603 to 0.737 | |||
| 35–39 | 0.538*** | 0.484 to 0.597 | 0.543*** | 0.488 to 0.604 | 0.602*** | 0.540 to 0.671 | |||
| 40–44 | 0.526*** | 0.469 to 0.59 | 0.526*** | 0.468 to 0.592 | 0.599*** | 0.532 to 0.675 | |||
| 45–49 | 0.497*** | 0.433 to 0.572 | 0.493*** | 0.428 to 0.568 | 0.559*** | 0.484 to 0.645 | |||
| BMI of mother | |||||||||
| Thin | 1 | 1 | 1 | ||||||
| Normal | 0.955 | 0.901 to 1.012 | 0.970*** | 0.915 to 1.028 | 0.923** | 0.870 to 0.979 | |||
| Obese | 0.816*** | 0.765 to 0.871 | 0.841*** | 0.787 to 0.898 | 0.780*** | 0.730 to 0.834 | |||
| Education | |||||||||
| No formal | 1 | 1 | 1 | ||||||
| Primary | 0.531*** | 0.509 to 0.554 | 0.56803 | 0.545 to 0.592 | 0.779*** | 0.745 to 0.815 | |||
| Secondary | 0.502*** | 0.479 to 0.527 | 0.54016 | 0.514 to 0.567 | 0.676*** | 0.642 to 0.713 | |||
| Tertiary | 0.392*** | 0.354 to 0.435 | 0.43671 | 0.393 to 0.485 | 0.534*** | 0.480 to 0.595 | |||
| Marital status | |||||||||
| Never married | 1 | ||||||||
| Married | 1.071 | 0.996 to 1.152 | 1.161*** | 1.074 to 1.255 | 1.030 | 0.951 to 1.116 | |||
| Living with a partner | 0.975 | 0.900 to 1.057 | 1.044 | 0.958 to 1.137 | 1.036 | 0.949 to 1.131 | |||
| Widowed/divorced/separated | 0.979 | 0.893 to 1.072 | 1.062 | 0.968 to 1.165 | 1.102* | 1.003 to 1.211 | |||
| Employment status | |||||||||
| No | 1 | ||||||||
| Yes | 0.968 | 0.934 to 1.004 | 0.982 | 0.947 to 1.018 | 0.911*** | 0.878 to 0.946 | |||
| Antenatal care | |||||||||
| No | 1 | ||||||||
| Yes | 0.912** | 0.857 to 0.969 | 0.940* | 0.884 to 1.000 | 0.931* | 0.874 to 0.991 | |||
| Wealth | |||||||||
| Poor | 1 | ||||||||
| Middle | 0.928** | 0.885 to 0.973 | 0.917*** | 0.874 to 0.962 | |||||
| Rich | 0.830*** | 0.790 to 0.873 | 0.888*** | 0.844 to 0.935 | |||||
| Household size | |||||||||
| Small | 1 | 1 | |||||||
| Medium | 1.109*** | 1.066 to 1.156 | 1.095*** | 1.051 to 1.142 | |||||
| Large | 1.472*** | 1.383 to 1.566 | 1.240*** | 1.163 to 1.321 | |||||
| Age of household head | |||||||||
| Young-aged adults | 1 | ||||||||
| Middle-aged adults | 1.087*** | 1.041 to 1.136 | 1.012 | 0.968 to 1.058 | |||||
| Old-aged adults | 1.088** | 1.026 to 1.153 | 0.966 | 0.910 to 1.025 | |||||
| Sex of household head | |||||||||
| Male | 1 | ||||||||
| Female | 0.945** | 0.903 to 0.989 | 0.966 | 0.923 to 1.011 | |||||
| Access to electricity | |||||||||
| No | 1 | ||||||||
| Yes | 1.090*** | 1.039 to 1.143 | 0.896*** | 0.853 to 0.941 | |||||
| Type of toilet facility | |||||||||
| Unimproved | 1 | ||||||||
| Improved | 0.856*** | 0.824 to 0.889 | 0.927*** | 0.892 to 0.963 | |||||
| Source of drinking water | |||||||||
| Unimproved | 1 | ||||||||
| Improved | 1.046** | 1.008 to 1.085 | 1.046** | 1.008 to 1.086 | |||||
| Geographic region | |||||||||
| Western Africa | 1 | ||||||||
| Eastern Africa | 0.397*** | 0.380 to 0.415 | |||||||
| Central Africa | 0.562*** | 0.532 to 0.595 | |||||||
| Southern Africa | 0.497*** | 0.451 to 0.548 | |||||||
| Random effects | |||||||||
| PSU variance (95% CI) | 0.02 (0.02 to 0.03) | 0.01 (0.02 to 0.03) | 0.02 (0.01 to 0.03) | 0.02 (0.01 to 0.03) | 0.02 (0.01 to 0.03) | ||||
| ICC | 0.007 | 0.007 | 0.006 | 0.005 | 0.005 | ||||
| LR test | 157.11*** | 162.27*** | 33.77*** | 32.09*** | 31.14*** | ||||
| Wild χ2 | Reference | 638.08*** | 5397.49*** | 5699.37*** | 7017.31*** | ||||
| Model fitness | |||||||||
| Log-likelihood | −79 952 | −79 633.85 | −41 560.3 | −41 341.3 | −40 448.4 | ||||
| AIC | 2E+05 | 15 9277.7 | 83 182.53 | 82 764.6 | 80 984.8 | ||||
| Number of clusters | 1382 | 1382 | 1382 | 1382 | 1382 | ||||
*p<0.05; **p<0.01; ***p<0.001.
1, Ref; AIC, Akaike’s information criterion; AOR, adjusted OR; ICC, Intraclass Correlation Coefficient; LR, Likelihood ratio; PSU, primary sampling units.