Access to intensive neonatal care and neonatal survival in low birthweight infants: a population study in Norway.

This study evaluates the impact of regional differences in access to intensive neonatal care on neonatal survival in geographically defined populations of 4,692 low birthweight births in Norway 1979-81. For infants weighting 1,250 to 2,499 g our results are consistent with the existence of a dose-response association between neonatal survival and the level of immediate access to intensive neonatal care. Although not statistically significant, there was a clear gradient in the risk of mortality within 24 hours. A similar pattern of survival could not be consistently demonstrated for infants weighing less than 1,250 g.