1. Department of Pediatric Dentistry and Orthodontics; Faculty of Dentistry; Universidad de La Frontera; Temuco Chile
2. Center for Research in Epidemiology; Economics and Oral Public Health (CIEESPO); Faculty of Dentistry; Universidad de La Frontera; Temuco Chile
3. Universitat Autònoma de Barcelona; Barcelona Spain
4. Iberoamerican Cochrane Centre; Biomedical Research Institute Sant Pau (IIB Sant Pau); Barcelona Spain
5. CIBER Epidemiología y Salud Pública (CIBERESP); Barcelona Spain
6. Faculty of Dentistry; Universidad San Sebastian; Puerto Montt Chile
7. Health Services Research Group; IMIM (Hospital del Mar Medical Research Institute); Barcelona Spain