1. Department of Public Health and Epidemiology; Riga Stradins University; Latvia
2. Department of Health Sciences; University of Jyväskylä; Finland
3. Department of Child and Adolescent Psychiatry, Psychotherapy, and Psychosomatics; University Medical Center Hamburg-Eppendorf; Hamburg Germany
4. Child and Adolescent Health Research Unit; University of St Andrews; UK
5. Ludwig Boltzmann Institute; Vienna Austria
6. Department of Public Health and Paediatrics; University of Torino; Italy
7. Active Living Institute; Faculty of Physical Culture; Palacky University; Olomouc Czech Republic
8. National Institute of Public Health; University of Southern Denmark; Copenhagen Denmark