Validity of New Ballard Score until 7th day of postnatal life in moderately preterm neonates.
OBJECTIVE
The New Ballard Score (NBS) has been evaluated only until 96 h of age. We studied the validity and reliability of NBS for gestational age (GA) assessment on days 1, 5 and 7 of postnatal age (PNA).


METHODS
This prospective, analytical study was conducted in a level III neonatal unit.


METHODS
Neonates born at a GA of 29-35 weeks (based on accurate last menstrual period (LMP)) were eligible. Encephalopathy, malformations, and unstable vitals were exclusion criteria. LMP-based GA was the gold standard. NBS was assessed within 24 h of birth by one rater, and two raters assessed NBS on days 5 and 7. All were blinded to LMP and one anothers' ratings. Recruitment continued until >100 subjects were enrolled with > or =25 in each LMP-based GA group: 29-30 weeks, 31-32 weeks, 33-34 weeks and 35 weeks.


RESULTS
Correlation of GA assessed on day 7 with gold standard.


RESULTS
129 neonates were studied. NBS-based GA on days 5 or 7 did not differ from the gold standard GA by more than 2 weeks in any subject. On day 7, NBS overestimated GA in 26.7% and underestimated GA in 19.8% cases; all discrepancies were < or =2 wks. Compared to gold standard GA, the intra-class correlations (ICCs) of the gold standard GA and the NBS-based GA of the day 1 rater, day 5 rater and day 7 rater were 0.94, 0.94 and 0.92, respectively. ICCs for inter-rater reliability on day 5 and day 7 were 0.97 and 0.96, respectively. Compared to the day 1 rater's raw NBS, the ICCs of day 5 and day 7 raters' total scores were 0.98 and 0.97, respectively; of day 5 and day 7 raters' neurological scores were 0.98 and 0.97; and of day 5 and day 7 raters' physical scores were 0.92 and 0.88. All ICCs mentioned above had p values <0.001.


CONCLUSIONS
NBS is a valid and reliable clinical tool for GA assessment until day 7. It slightly overestimates the GA with increasing PNA. Neurological signs are more reliable than physical ones.
Sasidharan
K
K
Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Dutta
S
S
Narang
A
A
D000886:Anthropometry / Q000379:methods; D005260:Female; D005835:Genitalia / Q000254:growth & development*; D005865:Gestational Age; D006801:Humans; D007230:Infant, Low Birth Weight / Q000254:growth & development*; D007231:Infant, Newborn; D007234:Infant, Premature / Q000254:growth & development*; D008297:Male; D009460:Neurologic Examination; D010808:Physical Examination; D011446:Prospective Studies; D015203:Reproducibility of Results; D012867:Skin / Q000254:growth & development*