Table 1

Characteristics of patients included in model derivation and external validation

CharacteristicDerivationExternal validation
NETS, n=4840SENSS, n=5427*NETS, n=1443SENSS, n=1627*
n†%n†%n†%n†%
Sex
 Male2605542942548505996260
 Missing120.320.1
Birth weight (kg)
 <1310.6320.6101101
 1.0–<1.511521363403453
 1.5–<2.51043221182223162236122
 2.5–4.0343871384871100269112669
 >4.020442294745855
 Missing90.210.1
Mode of delivery
 Spontaneous vaginal26975731075789763101863
 Assisted vaginal10.0260.10010.1
 Breech4011022191342
 Caesarean section1999422212415093657435
 Missing1453181
Outborn§‡
 Yes10721232574604
 Missing0000
HIV exposure
 Exposed28763386745936
 Missing2776806
Outcome
 Alive437490491891130090147691
 Dead4479509913791511
 Missing190.460.4
  • *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.