What is survival analysis, and when should I use it?

1. Divisao de Pneumologia, Instituto do Coracao – InCor – Hospital das Clinicas, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, Brasil. 2. Methods in Epidemiologic, Clinical and Operations Research–MECOR–program, American Thoracic Society/Asociacion Latinoamericana del Torax. 3. Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA. INTRODUCTION