1. Department of Oral Sciences, Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand;
2. Department of Preventive and Social Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand;
3. Dunedin Multidisciplinary Health and Development Research Unit, Department of Preventive and Social Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; and
4. Community Dental Health Services Research Unit, Faculty of Dentistry, University of Toronto, ON, Canada