Characteristics of patients included in model derivation and external validation
| Characteristic | Derivation | External validation | ||||||
| NETS, n=4840 | SENSS, n=5427* | NETS, n=1443 | SENSS, n=1627* | |||||
| n† | % | n† | % | n† | % | n† | % | |
| Sex | ||||||||
| Male | 2605 | 54 | 2942 | 54 | 850 | 59 | 962 | 60 |
| Missing | 12 | 0.3 | 2 | 0.1 | ||||
| Birth weight (kg) | ||||||||
| <1 | 31 | 0.6 | 32 | 0.6 | 10 | 1 | 10 | 1 |
| 1.0–<1.5 | 115 | 2 | 136 | 3 | 40 | 3 | 45 | 3 |
| 1.5–<2.5 | 1043 | 22 | 1182 | 22 | 316 | 22 | 361 | 22 |
| 2.5–4.0 | 3438 | 71 | 3848 | 71 | 1002 | 69 | 1126 | 69 |
| >4.0 | 204 | 4 | 229 | 4 | 74 | 5 | 85 | 5 |
| Missing | 9 | 0.2 | 1 | 0.1 | ||||
| Mode of delivery | ||||||||
| Spontaneous vaginal | 2697 | 57 | 3107 | 57 | 897 | 63 | 1018 | 63 |
| Assisted vaginal | 1 | 0.02 | 6 | 0.1 | 0 | 0 | 1 | 0.1 |
| Breech | 40 | 1 | 102 | 2 | 19 | 1 | 34 | 2 |
| Caesarean section | 1999 | 42 | 2212 | 41 | 509 | 36 | 574 | 35 |
| Missing | 145 | 3 | 18 | 1 | ||||
| Outborn§‡ | ||||||||
| Yes | 107 | 2 | 123 | 2 | 57 | 4 | 60 | 4 |
| Missing | 0 | 0 | 0 | 0 | ||||
| HIV exposure | ||||||||
| Exposed | 287 | 6 | 338 | 6 | 74 | 5 | 93 | 6 |
| Missing | 277 | 6 | 80 | 6 | ||||
| Outcome | ||||||||
| Alive | 4374 | 90 | 4918 | 91 | 1300 | 90 | 1476 | 91 |
| Dead | 447 | 9 | 509 | 9 | 137 | 9 | 151 | 1 |
| Missing | 19 | 0.4 | 6 | 0.4 | ||||
*Data presented are after multiple imputation. The multiple imputation filled in the missing values while preserving the pattern of distribution observed in the original data sets (online supplemental table 8).
†Denominators for the variables obtained by subtracting the missing data from the sample (4840 for derivation, 1443 for external validation)
‡Outborn refers to neonates admitted to the unit having been born either in another facility, at home or on the way to hospital
NETS, Neonatal Essential Treatment Score; SENSS, Score for Essential Symptoms and Signs.