New Ballard Score, expanded to include extremely premature infants

The Ballard Maturational Score was refined and expanded to achieve greater accuracy and to include extremely premature neonates. To test validity, accuracy, interrater reliability, and optimal postnatal age at examination, the resulting New Ballard Score (NBS) was assessed for 578 newly born infants and the results were analyzed. Gestational ages ranged from 20 to 44 weeks and postnatal ages at examination ranged from birth to 96 hours. In 530 infants, gestational age by last menstrual period was confirmed by agreement within 2 weeiks with gestational age by prenatal ultrasonography (C-GLMP). For these infants, correlation between gestational age by NBS and C-GLMP was 0.97. Mean differences between gestational age by NBS and C-GLMP were 0.32±1.58 weeks and 0.15±1.46 weeks among the extremely premature infants (