1. Department of Medical Epidemiology and Biostatistics; Karolinska Institutet; Stockholm Sweden
2. Centre for Pharmacoepidemiology, Department of Medicine; Karolinska Institutet; Stockholm Sweden
3. Public Healthcare Services Committee Administration; Stockholm County Council; Stockholm Sweden
4. Department of Pediatrics; Örebro University Hospital; Örebro Sweden
5. Clinical epidemiology unit, Department of Medicine; Karolinska Institutet; Stockholm Sweden
6. Department of Women's and Children's Health, Astrid Lindgren Children's Hospital; Karolinska University Hospital; Stockholm Sweden