1. Department of Pediatrics; St. Marien-Hospital; Bonn Germany
2. Institute of Medical Biometry; Informatics und Epidemiology (IMBIE); Bonn Germany
3. Children's Hospital; Osnabrück Germany
4. Department for Pediatrics; Helios Klinikum; Aue Germany
5. Children's Hospital; University of Cologne; Cologne Germany
6. Kinderarztpraxis Laurensberg; Aachen Germany
7. Children's Hospital; Hannover Medical School; Hannover Germany
8. Department of Pediatric Pneumology and Immunology; Charité-Universitätsmedizin; Berlin Germany