Years of birth | Birthweight range | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
500-749 g | 750-999 g | 500-999 g | |||||||||
1979-80 | 1985-87 | 1991-92 | 1979-80 | 1985-87 | 1991-92 | 1979-80 | 1985-87 | 1991-92 | |||
Total livebirths | 129 | 223 | 169 | 222 | 337 | 260 | 351 | 560 | 429 | ||
Survived to 2 years of age (%) | 8 (6.2%) | 21 (9.4%) | 54 (32.0%) | 81 (36.5%) | 191 (56.7%) | 187 (71.9%) | 89 (25.4%) | 212 (37.9%) | 241 (56.2%) |
A. Odds ratio (OR) and 95 % confidence interval (CI) for survival between 500 - 749 g and 750 - 999 g birthweight subgroups. 1979-80, OR 4.9, 95% CI 3.0 to 8.1. 1985-87, OR 7.4, 95% CI 5.2 to 10.5. 1991-92, OR 5.1, 95% CI, 3.4 to 7.5.
B. OR and 95 % CI for survival between eras. 500 - 999 g birthweight: 1985-87vs 1979-80, OR 1.76, 95% CI 1.32 to 2.33. 1991-92vs 1985-87, OR 2.09, 95% CI 1.62 to 2.69. 500 - 749 g birthweight subgroup: 1985-87 vs 1979-80, OR 1.53, 95% CI 0.70 to 3.36, not significant. 1991-92vs 1985-87, OR 4.28, 95% CI 2.57 to 7.10. 750 - 999 g birthweight subgroup: 1985-87 vs 1979-80, OR 2.24, 95% CI 1.60 to 3.14. 1991-92 vs 1985-87, OR 1.93, 95% CI 1.38 to 2.69.