1. Division of Pediatric Infectious Diseases, Vienna Vaccine Safety Initiative, Berlin, Germany
2. Department of Pediatrics, Charité University Medical Center, Berlin, Germany
3. Division of Epidemiology and Public Health, University of Nottingham, Nottingham, UK
4. Department of Mathematics and Computer Science, Freie Universität Berlin, Berlin, Germany
5. National Reference Centre for Influenza and Other Respiratory Viruses, Robert Koch Institute, Berlin, Germany
6. Clinical Data Standards Interchange Consortium (CDISC), Austin, TX, USA