Quality of care of VLBW-neonates: relationship between unit volume and outcome is different between metropolitan and rural regions

Recent studies from predominantly rural areas in Germany show that neonatal outcome of very low birth weight (VLBW) neonates is (on average) inferior with lower NICU (neonatal intensive care unit) volume. However, there are no data available which show that study results of one specific region can be transferred to other areas with possibly different medical infrastructure and needs.It was investigated whether a systematic difference of treatment quality between smaller (1000-2000 births/year; < or =20 neonatal beds) vs. larger neonatal centres in Berlin (>3000 births/year; >20 neonatal beds) exists. Furthermore, the results are compared to data from a rural region in order to discuss transferability between regions.Retrospectively, completely, and for the first time, the data of all centres which treat VLBW neonates (< or =1500 g birth weight) in the city-state of Berlin, Germany, from the years 2003/2004 were reviewed.Our study showed no difference in the treatment quality of smaller vs. larger neonatal units in Berlin. This result differs from those of a study in Baden-Württemberg, a predominantly rural state, with different medical infrastructure than Berlin.The present study suggests that regional investigations on the infrastructure vs. treatment outcome are not transferable between areas. Patient volume/unit appears inadequate for predicting the future treatment quality of neonatal departments. Direct quality indicators are stable for the assessed departments and should be preferably used to organize medical infrastructure.