Development, Reliability, and Testing of a New Rating Scale for Neonatal Encephalopathy.

OBJECTIVE To develop and test the Neonatal Encephalopathy - Rating Scale (NE-RS), a new rating scale to grade the severity of neonatal encephalopathy (NE) within the first six hours after birth. STUDY DESIGN A three-phase process was conducted: 1) design of a comprehensive scale that would be specific, sensitive, brief, and unsophisticated; 2) evaluation in a cohort of infants with neonatal encephalopathy and healthy controls; 3) validation with brain magnetic resonance imaging (MRI) findings and outcome at two years of age. RESULTS We evaluated the NE-RS in 54 infants with NE and 28 healthy infants. The NE-RS had excellent internal consistency (Cronbach`s alpha coefficient: 0.93 [95%CI 0.86-0.94]) and reliability (intra-class correlation coefficient in the NE cohort 0.996 [95%CI 0.993-0.998; P<0.001]). Alertness, posture, motor response, and spontaneous activity were the top discriminators for degrees of NE. The cut-off value for mild vs moderate NE was 8 points (area under the curve [AUC] 0.99, 95%CI 0.85-1.00) and for moderate vs severe NE, 30 points (AUC 0.93, 95%CI 0.81-0.99). The NE-RS was significantly correlated with the MRI score (Spearman Rho 0.77, P < .001) and discriminated infants who had an adverse outcome (AUC 0.91, 95%CI 0.83-0.99, sensitivity 0.82, specificity 0.81, positive predictive value 0.87, negative predictive value 0.74). CONCLUSIONS The NE-RS is reliable and performs well in reflecting the severity of NE within the first six hours after birth. This tool could be useful when assessing clinical criteria for therapeutic hypothermia in NE.