[1] Univ Barcelona, H Clin, Inst Invest Biomed August Pi I Sunyer, E-08007 Barcelona, Spain
[2] Corp Sanitaria Parc Tauli Hosp Sabadell, Sabadell, Spain
[3] Hosp Univ Valladolid, Valladolid, Spain
[4] Hosp Univ Virgen Rocio, Seville, Spain
[5] Hosp Reina Sofia, Cordoba, Spain
[6] Hosp Gen Valle Hebron, Barcelona, Spain
[7] Duke Univ, Med Ctr, Durham, NC 27706 USA
[8] Hosp Clin San Carlos, Madrid, Spain
[9] Hosp Son Llatzer, Mallorca, Spain
[10] Hosp Xeral Vigo, Lugo, Spain
[11] Hosp Ramon & Cajal, E-28034 Madrid, Spain
[12] Hosp Princesa, Madrid, Spain
[13] Clin Univ Navarra, Pamplona, Spain
[14] Hosp Marques Valdecilla, Fac Med, Santander, Spain
[15] Bellvitge Hosp, Barcelona, Spain
[16] Hosp Carlos Haya, Malaga, Spain