1. Department of Child and Adolescent Psychiatry and Psychotherapy; University of Ulm; Ulm Germany
2. Institute of Epidemiology and Medical Biometry; University of Ulm; Ulm Germany
3. Department of Paediatrics and Adolescent Medicine; Medical University of Vienna; Vienna Austria
4. Department of Paediatrics; Kinderklinik Amsterdamerstr; Cologne Germany
5. Department of Child and Adolescent Medicine; University of Ulm; Ulm Germany