1. American University of Beirut; Department of Internal Medicine; Riad El Solh St Beirut Lebanon
2. American University of Beirut; Faculty of Medicine; Beirut Lebanon
3. Faculty of Medicine, Pontificia Universidad Católica de Chile; Department of Internal Medicine, Evidence Based Health Care Program; Lira 44, Santiago Santiago Región metropolitana Chile
4. Regina Elena National Cancer Institute; Division of Medical Oncology B - Scientific Direction; Via Elio Chianesi 53 Rome Italy 00144
5. Regina Elena National Cancer Institute; Biostatistics-Scientific Direction; Via Elio Chianesi 53 Rome Italy 00144
6. National Cancer Institute Regina Elena; Department of Epidemiology; Via Elio Chianesi 53 Rome Italy 00144
7. McMaster University; Departments of Clinical Epidemiology and Biostatistics and of Medicine; 1280 Main Street West Hamilton ON Canada L8N 4K1