1. Division of Hygiene and Epidemiology, Medical University of Gdańsk, Gdańsk, Poland
2. Kungsmarken Health Center, Karlskrona, Sweden
3. Division of Preventive Medicine & Education, Medical University of Gdańsk, Gdańsk, Poland
4. Department of Child and Adolescent Psychiatry, Medical University of Łódź, Łódź, Poland