Early clinical characteristics of case and control infants
| Clinical characteristics | Cases n=210 n (%) | Controls n=409 n (%) | p Value |
| Apgar 1 min | |||
| ≤3 | 68/202 (33.7) | 2/405 (0.5) | <0.0001† |
| 4–6 | 116/202 (57.4) | 15/405 (3.7) | |
| ≥7 | 18/202 (8.9) | 388/405 (95.8) | |
| Apgar at 5 min | |||
| ≤3 | 8/185 (4.3) | 1/399 (0.25) | <0.0001† |
| 4–6 | 126/185 (68.1) | 1/399 (0.25) | |
| ≥7 | 51/185 (27.6) | 397/399 (99.5) | |
| Need for any resuscitation | |||
| No | 6/162 (3.7) | 331/378 (85.1) | <0.001 |
| Yes | 156/162 (96.3) | 57/378 (15.1) | |
| Clinical features | |||
| Grade of encephalopathy* | |||
| Mild | 25/210 (11.9) | – | |
| Moderate | 114/210 (54.3) | – | |
| Severe | 71/210 (33.8) | – | |
| Absent suck | 166/209 (79.4) | – | |
| Clinical seizures | 104/210 (49.5) | – | |
| Comatose | 53/210 (25.2) | – | |
| Neonatal case fatality | 70/208 (33.7) | 1/396 (0.3) | <0.001 |
*Encephalopathy graded according to Sarnat & Sarnat.
†chi-squared for trendchi-squared for trend.