[1] Hosp Clin Univ Salamanca, Salamanca, Spain
[2] Hosp Univ & Politecn La Fe, Valencia, Spain
[3] Hosp Clin Barcelona, Barcelona, Spain
[4] Hosp Univ Virgen del Rocio, Seville, Spain
[5] Hosp Univ Reina Sofia, Cordoba, Spain
[6] Hosp Univ Ramon & Cajal, Madrid, Spain
[7] Hosp Santa Creu & Sant Pau, Barcelona, Spain
[8] Hosp Univ Marques de Valdecilla, Santander, Spain
[9] Hosp Univ La Princesa, Madrid, Spain
[10] Hosp Univ Jerez de la Frontera, Jerez de la Frontera, Spain
[11] Hosp Gen Univ Morales Meseguer, Murcia, Spain
[12] Hosp Univ Cent Asturias, Oviedo, Spain
[13] Hosp Badalona Germans Trias & Pujol, Badalona, Spain
[14] Complejo Hosp Univ Vigo, Vigo, Spain
[15] Hosp Univ Donostia, San Sebastian, Spain
[16] Hosp Reg Univ Malaga, Malaga, Spain
[17] Hosp Univ Vall dHebron, Barcelona, Spain
[18] Hosp Univ Gran Canaria Doctor Negrin, Las Palmas Gran Canaria, Spain
[19] Hosp Univ Puerta Hierro Majadahonda, Madrid, Spain
[20] Merck & Co Inc, Kenilworth, NJ USA
[21] Merck Sharp & Dohme Ltd, Madrid, Spain
[22] Pharmacoecon & Outcomes Res Iberia, Madrid, Spain
[23] Hosp Clin Univ Valencia, Valencia, Spain