Keiser, Olivia; Orrell, Catherine; Egger, Matthias; Wood, Robin; Brinkhof, Martin W G; Furrer, Hansjakob; vCutsem, Gilles; Ledergerber, Bruno; Boulle, Andrew; (IeDEA-SA), for the Swiss HIV Cohort Study (SHCS) and the International Epidemiologic Databases(Public Library of Science, 2008)