1. Department of Paediatrics; School of Medicine; University of Eastern Finland; Kuopio Finland
2. Department of Paediatrics; North-Karelia Central Hospital; Joensuu Finland
3. Department of Paediatrics; Kuopio University Hospital; Kuopio Finland
4. Department of Surgery; Kuopio University Hospital; Kuopio Finland
5. Paediatric Research Centre; Tampere University and University Hospital; Tampere Finland