1. Hospital del Mar-IMIM; Department of Nephrology; Passeig Marítim 25-29 Barcelona Spain 08003
2. The University of Sydney; Sydney School of Public Health; Edward Ford Building A27 Sydney NSW Australia 2006
3. The University of Sydney at Westmead; Centre for Transplant and Renal Research, Westmead Millennium Institute; Westmead NSW Australia 2145
4. The Children's Hospital at Westmead; Cochrane Renal Group, Centre for Kidney Research; Westmead NSW Australia 2145
5. Hospital Ramon y Cajal; CIBER Epidemiologia y Salud Publica (CIBERESP); Ctra. Colmenar km, 9.1 Madrid Spain 28047
6. Unidad de Bioestadística, Hospital Ramón y Cajal; Madrid Spain
7. Ramon y Cajal Institute for Health Research (IRYCIS), CIBER Epidemiology and Public Health (CIBERESP) and Cochrane Collaborating Centre; Clinical Biostatistics Unit; Ctra. Colmenar km 9,100 Madrid Madrid Spain 28034
8. CIBER Epidemiologia y Salud Publica (CIBERESP); Madrid Spain