Table 9 Differentials in infant mortality rates (source: household survey)
From: Health and survival of young children in southern Tanzania
| Â | Category | Deaths | Child-years | Mortality rate per 1000 child-years | RR | 95% CI* | P* |
|---|---|---|---|---|---|---|---|
Year (July–June) | 2001–2 | 184 | 2,218.8 | 82.9 | 1 |  | 0.72 (for trend P = 0.75) |
|  | 2002–3 | 183 | 2,324.7 | 78.7 | 0.95 | 0.8 – 1.2 |  |
|  | 2003–4 | 227 | 2,659.8 | 85.3 | 1.03 | 0.8 – 1.3 |  |
Mother's age at delivery | 20–29 | 261 | 3,398.7 | 76.8 | 1 |  | 0.005 |
|  | 30–39 | 124 | 1,702.2 | 72.8 | 0.95 | 0.8 – 1.2 |  |
|  | 40–49 | 27 | 364.5 | 74.1 | 0.96 | 0.6 – 1.4 |  |
|  | Under 20 | 181 | 1,718.8 | 105.3 | 1.37 | 1.1 – 1.7 |  |
Mother's education | One or more years | 399 | 5,123.9 | 77.9 | 1 | Â | 0.038 |
|  | None | 194 | 2,063.6 | 94.0 | 1.21 | 1.0 – 1.4 |  |
Sex | Girls | 287 | 3,537.7 | 81.1 | 1 | Â | 0.70 |
|  | Boys | 307 | 3,665.5 | 83.8 | 1.03 | 0.9 – 1.2 |  |
Twins | Singleton | 518 | 6,980.1 | 74.2 | 1 | Â | <0.0001 |
|  | Twin | 76 | 223.2 | 340.5 | 4.59 | 3.4 – 6.2 |  |
Age | 0–27 days | 337 | 574.2 | 586.9 | 1 |  | <0.0001 |
|  | 28–365 days | 257 | 6,629.0 | 38.8 | 0.07 | 0.06 – 0.08 |  |
Ethnic group of household head | Makonde | 220 | 3,075.8 | 71.5 | 1 | Â | 0.01 |
|  | Mwera | 246 | 2,867.3 | 85.8 | 1.20 | 1.0 – 1.4 |  |
|  | Yao | 29 | 318.7 | 91.0 | 1.27 | 0.8 – 2.0 |  |
|  | Other | 99 | 926.2 | 106.9 | 1.49 | 1.2 – 1.9 |  |
Gender of household head | Male | 478 | 5,695.9 | 83.9 | 1 | Â | 0.48 |
|  | Female | 116 | 1,493.2 | 77.7 | 0.93 | 0.7 – 1.1 |  |
SES quintile of household | Poorest | 109 | 1,291.1 | 84.4 | 1 | Â | 0.90 (test for trend) |
|  | Very poor | 122 | 1,577.9 | 77.3 | 0.92 | 0.7 – 1.2 |  |
|  | Poor | 102 | 1,182.1 | 86.3 | 1.02 | 0.8 – 1.4 |  |
|  | Less poor | 129 | 1,540.9 | 83.7 | 0.99 | 0.8 – 1.3 |  |
|  | Least poor | 120 | 1,513.7 | 79.3 | 0.94 | 0.7 – 1.2 |  |
Distance to nearest health facility | <5 km | 363 | 4,778.9 | 76.0 | 1 | Â | 0.02 |
|  | ≥ 5 km | 196 | 2,061.2 | 95.1 | 1.25 | 1.0 – 1.5 |  |
Effect of child's age on the relationship between twinning and mortality: | |||||||
Twins under 28 days (neonates) | Singleton | 280 | 556.6 | 503.0 | 1 | Â | <0.0001 |
|  | Twin | 57 | 17.6 | 3,242.6 | 6.45 | 4.5 – 9.2 |  |
Twins over 28 days (1–11 m) | Singleton | 238 | 6,423.4 | 37.1 | 1 |  | <0.0001 |
|  | Twin | 19 | 205.6 | 92.4 | 2.49 | 1.5 – 4.0 |  |
Effect of child's age on the relationship between maternal education and mortality: | |||||||
In neonates: Mother's education | ≥ 1 year | 238 | 407.4 | 584.3 | 1 |  | 0.93 |
|  | None | 98 | 165.9 | 590.8 | 1.01 | 0.8 – 1.3 |  |
In 1–11 month olds: Mother's education | ≥ 1 year | 161 | 4,716.7 | 34.1 | 1 |  | 0.003 |
|  | None | 96 | 1,897.8 | 50.6 | 1.48 | 1.1 – 1.9 |  |
Effect of distance from the health facility on the relationship between maternal education and mortality | |||||||
In those living < 5 km from a health facility: mothers education | ≥ 1 year | 239 | 3,466. | 68.9 | 1 |  |  |
|  | None | 123 | 1,305.3 | 94.2 | 1.4 | 1.1 – 1.7 | 0.005 |
In those living ≥ 5 km from a health facility: mothers education | ≥ 1 year | 140 | 1,421.5 | 98.5 | 1 |  |  |
|  | None | 56 | 637.9 | 87.8 | 0.9 | 0.7 – 1.2 | 0.47 |