Presented at the Neonatal Society 2012 Spring Meeting.
Harijan P1, Beer C2, Glazebrook C2, Israel C3, Marlow N4, Whitelaw A, Johnson S1
1 University of Leicester, UK
2 University of Nottingham, UK
3 University of Bristol, UK
4 University College London, UK
Background: Early prediction of long-term outcome remains challenging for very preterm infants. Detailed neonatal neurobehavioural assessments of neurobehavioural function may afford improved prediction. This study explored the discriminative, construct and predictive validity of the Neurobehavioral Assessment of the Preterm Infant (NAPI). Ethical approval was granted by the South-West Multicentre Research Ethics Committee and the local Research Ethics Committee in each centre.
Methods: The NAPI was conducted at 35 weeks post-menstrual age for 170 infants born <32 weeks. Cognitive and motor development was assessed at 2 years corrected age using the MDI and PDI of Bayley Scales of Infant Development-II (BSID-II) for 159 infants. Z-scores for NAPI clusters were used to adjust for postmenstrual age at assessment.
Results: Discriminative validity: Only mean NAPI motor and irritability z-scores were significantly different between very preterm (29-32w) and extremely preterm (<28w) infants. Results regarding construct validity were variable: there were weak but significant correlations between NAPI motor z-scores and gestational age (r=-0.23; p=0.003), days in NICU (r=-0.24; p=0.001); NAPI alertness z-scores and days in NICU (r=-0.16; p=0.037); and NAPI irritability z-scores and gestational age (r=0.21; p=0.006). There were no significant associations with other neonatal markers of adverse outcome. Only NAPI irritability z-scores were significantly correlated with MDI scores (r=-0.16; p=0.040). However, these accounted for little additional variance in MDI after adjustment for neonatal factors (ΔR2=0.035; p=0.012).
Conclusion: We found little evidence of the utility of the NAPI as a measure of short-term neurobehavioural function or as a predictor of long-term neurodevelopmental outcomes in very preterm infants. The NAPI may have greater predictive power when used serially to detect delayed neurobehavioural maturation during the neonatal period.
Corresponding author: Dr Pooja Harijan, University of Leicester
Korner AF, Thorn VA. Neurobehavioral Assessment of the Preterm Infant. The Psychological Corporation. Harcourt, Brace & Jovanovich, Inc.; 1990.