Maria Lodefalk1,2, Ola Nilsson1,3. 1. Department of Paediatrics, School of Medical Sciences, Örebro University, Örebro, Sweden. 2. University Health Care Research Center, Örebro University, Örebro, Sweden. 3. Division of Paediatric Endocrinology, Department of Women's and Children's Health, Karolinska Institutet and University Hospital, Stockholm, Sweden.