1. School of Medicine, University of Split; Department of Research in Biomedicine and Health; Soltanska 2 Split Croatia 21 000
2. School of Dentistry, The University of Manchester; Cochrane Oral Health Group; Coupland III Building, Oxford Road Manchester UK M13 9PL
3. Faculty of General Dental Practice; Yorkshire Area; Orchard House Tollerton York North Yorkshire UK YO61 1PS
4. MTI Community College; Vancouver BC Canada
5. University of Dundee; Dental Health Services Research Unit; The Mackenzie Building Kirsty Semple Way Dundee Scotland UK DD2 4BF
6. Faculty of Medicine, University of Ottawa; Department of Medicine; Ottawa Ontario Canada K1H 8M5