1. Diagnostic Clinic, University Hospital of North Norway, Tromsø, Norway
2. NILU–Norwegian Institute of Air Research, Fram Centre, Tromsø, Norway
3. Department of Community Medicine, UIT–the Arctic University of Norway, Tromsø, Norway
4. Norwegian National Unit for Newborn Screening, Women and Children’s Division, Oslo University Hospital, Oslo, Norway
5. Institute of Clinical Medicine, UIT–the Arctic University of Norway, Tromsø, Norway
6. Department of Public Health, University of Pretoria, Pretoria, South Africa