[1] ErasmusMC, Med Informat, Rotterdam, Netherlands
[2] Clin Epidemiol, Aarhus, Denmark
[3] Jordi Gol Primary Care Res Inst, SIDIAP, Barcelona, Spain
[4] SIMG, HSD, Florence, Italy
[5] Pedianet, Padua, Italy
[6] GlaxoSmithKline, Res & Dev, Res Triangle Pk, NC USA