1 Institute for Medical Technology Assessment, and Institute of Health Policy and Management, Erasmus University Rotterdam, PO Box 1738, 3000 DR Rotterdam, Netherlands. Electronic address: uyl@bmg.eur.nl.
2 Institute for Medical Technology Assessment, and Institute of Health Policy and Management, Erasmus University Rotterdam, PO Box 1738, 3000 DR Rotterdam, Netherlands.
3 Department of Family Medicine and Primary Health Care, Ghent University, University Hospital, Gent, Belgium.