1. Radboud University Nijmegen Medical Centre; Department of Oral and Maxillofacial Surgery; Nijmegen The Netherlands
2. University Medical Center Utrecht; Department of Oral and Maxillofacial Surgery and Special Dental Care; Utrecht The Netherlands
3. Radboud University Nijmegen Medical Centre; Department for Health Evidence, Section Biostatistics; Nijmegen The Netherlands
4. University Medical Center Utrecht; Julius Center Sciences; Utrecht The Netherlands
5. Radboud University Nijmegen Medical Centre; Scientific Institute for Quality of Health Care; Nijmegen The Netherlands