Inter-rater reliability of the modified Sarnat examination in preterm infants at 32-36 weeks' gestation

To test the inter-rater reliability of the modified Sarnat neurologic examination in preterm neonates and to correlate abnormalities with the presence of perinatal acidosis.

Prospective study of 32-36 weeks' gestational age infants admitted to the neonatal intensive care unit. Each infant had two Sarnat examinations performed at <6 h, one by a gold standard (GS) study investigator, and the second either by (a) another GS examiner or (b) an attending physician (28 examiners), all blinded to clinical variables. Agreement was calculated using kappa (k) statistics.

One hundred and two (9, fetal acidosis) infants underwent a modified Sarnat examination. Among GS examiners, agreement was excellent (k > 0.8) except for Moro, while among all examiners agreement was very good (k > 0.7) except for both Moro and tone. Subgroup analysis at 32-34 weeks' showed fair/poor Moro compared to excellent agreement at ≥35 weeks. Increasing abnormalities correlated with acidosis (r = -0.6, P < 0.01).

Strong inter-rater reliability for the modified Sarnat was observed except for tone and Moro in preterm infants. Experience of the examiners resulted in improved reliability in tone, while for the Moro agreement improved only beyond 35 weeks. Findings suggest the need of adjustment of the examination form specific for preterm infants.