1. School of Dentistry, The University of Manchester; Cochrane Oral Health Group; JR Moore Building Oxford Road Manchester UK M13 9PL
2. School of Dentistry, The University of Manchester; JR Moore Building Oxford Road Manchester UK M13 9PL
3. University of Dundee; Division of Oral Health Sciences; Dental Hospital & School Park Place Dundee Scotland UK DD1 4HR
4. The University of Manchester; Institute of Population Health, Centre for Primary Care; Oxford Road Manchester UK M13 9PL
5. Faculty of Medicine, University of Ottawa; Department of Medicine; Ottawa ON Canada K1H 8M5
6. University of Ottawa; Bruyère Research Institute; 85 Primrose Street Ottawa ON Canada K1N 5C8