1. Universidad de Chile, Escuela de Salud Pública, Santiago de Chile, Chile.
2. Send correspondence to Rafael Sepúlveda at dr.rafaelsepulveda@gmail.com or mariela.segura@redsalud.gov.cl
3. King's College London, Health Service and Population Research Department, IoPPN, London, United Kingdom of Great Britain and Northern Ireland.
4. Universidad Diego Portales, Santiago de Chile, Chile.