All weights | <1500 g1-150 | 1500–2499 g | ⩾ 2500 g | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Cases | Neonatal survivors | Rate | Rate LAS ⩾ 30% | Cases | Neonatal survivors | Rate | Rate LAS ⩾ 30% | Cases | Neonatal survivors | Rate | Rate LAS ⩾ 30% | Cases | Neonatal survivors | Rate | Rate LAS ⩾ 30% | ||||
1964–68 | 1091-151 | 64866 | 1.68 | 0.98 | 12 | 201 | 59.7 | 29.8 | 23 | 3511 | 6.55 | 3.88 | 73 | 61154 | 1.19 | 0.74 | |||
1969–73 | 76 | 54635 | 1.39 | 0.76 | 6 | 262 | 22.9 | 9.15 | 21 | 3279 | 6.40 | 1.71 | 49 | 51094 | 0.96 | 0.64 | |||
1974–78 | 77 | 45122 | 1.71 | 0.80 | 4 | 145 | 27.6 | 9.18 | 22 | 2473 | 8.90 | 4.29 | 51 | 42504 | 1.20 | 0.56 | |||
1979–83 | 96 | 48079 | 2.00 | 1.47 | 18 | 222 | 76.6 | 75.7 | 21 | 2675 | 8.22 | 6.27 | 57 | 45182 | 1.26 | 0.83 | |||
1984–88 | 109 | 48095 | 2.27 | 1.72 | 23 | 303 | 75.9 | 47.0 | 27 | 2797 | 9.65 | 7.72 | 59 | 44995 | 1.31 | 1.06 | |||
1989–93 | 117 | 47691 | 2.45 | 1.96 | 28 | 350 | 80.0 | 74.2 | 33 | 2795 | 11.8 | 11.5 | 56 | 44546 | 1.26 | 0.83 | |||
χ2 d.f. 5 | p<0.001 | p<0.001 | p<0.05 | p<0.01 | NS | p<0.01 | NS | NS | |||||||||||
χ2 for trend d.f. 1 | p<0.001 | p<0.001 | p<0.01 | p<0.01 | p<0.05 | p<0.001 | NS | NS |