[1] Katholieke Univ Leuven, LUCAS Ctr Care Res & Consultancy, Minderbroedersstr 8,Postal Box 5310, B-3000 Leuven, Belgium
[2] Katholieke Univ Leuven, Acad Ctr Gen Practice, Kapucijnenvoer 33j,Postal Box 7001, B-3000 Leuven, Belgium
[3] Katholieke Univ Leuven, Ctr Sociol Res, Parkstr 45,Postal Box 3601, B-3000 Leuven, Belgium