1. Department of Pediatrics, Turku University Hospital, Turku, Finland
2. Centre for Health Economics and
3. Information Unit, National Research and Development Centre for Welfare and Health, Helsinki, Finland
4. Department of Pediatrics, Hospital for Children and Adolescents, Helsinki, Finland
5. Department of Pediatrics, Oulu University Hospital, Oulu, Finland
6. Department of Pediatrics, Tampere University Hospital, Tampere, Finland