1. Post-Graduate Program in Epidemiology; Universidade Federal do Rio Grande do Sul; Porto Alegre Brazil
2. Institute for Research and Education, Hospital Moinhos de Vento; Porto Alegre Brazil
3. Internal Medicine Department, School of Medicine; Universidade Federal do Rio Grande do Sul; Porto Alegre Brazil
4. Statistics Department; Universidade Federal do Rio Grande do Sul; Porto Alegre Brazil
5. National Institute of Science and Technology for Health Technology Assessment, CNPq; Porto Alegre Brazil