[1] Maastricht Univ, Dept Hlth Care Studies, Sect Med Sociol, NL-6200 MD Maastricht, Netherlands
[2] Univ Maastricht, Care & Publ Hlth Res Inst, Maastricht, Netherlands
[3] Erasmus Univ, Res Inst Addict, Rotterdam, Netherlands
[4] Univ Maastricht, Dept Gen Practice, Maastricht, Netherlands
[5] Tilburg Univ, Fac Social & Behav Sci, NL-5000 LE Tilburg, Netherlands