1. Institute of Medical Informatics and Statistics, Kiel University University Hospital Schleswig‐Holstein Kiel Germany
2. Department of Periodontology, Oral Medicine and Oral Surgery Charité – University Medicine Berlin, Freie Universität Berlin, Humboldt‐Universität zu Berlin, and Berlin Institute of Health, Institute for Dental and Craniofacial Sciences Berlin Germany
3. Department of Conservative Dentistry, Unit of Periodontology University Medical Center Schleswig‐Holstein, Campus Kiel Kiel Germany
4. Department of Periodontology, Clinic of Preventive Dentistry and Periodontology University Medical Center of the Julius‐Maximilians‐University Würzburg Germany
5. Department of Conservative Dentistry, Periodontology and Preventive Dentistry Hannover Medical School Hannover Germany
6. Department of Conservative Dentistry and Periodontology, School of Dentistry Medical University Vienna Vienna Austria
7. Institute of Epidemiology Christian‐Albrechts University Kiel Germany
8. Institute of Clinical Molecular Biology Christian‐Albrechts University Kiel Germany
9. Department of Periodontology and Oral Biochemistry, Academic Centre for Dentistry Amsterdam (ACTA) University of Amsterdam and Vrije Universiteit Amsterdam Amsterdam The Netherlands
10. Department of Periodontology, Operative and Preventive Dentistry University of Bonn Bonn Germany