[1] Univ Amsterdam, Fac Social & Behav Sci, NL-1012 CX Amsterdam, Netherlands
[2] UCL, Hlth Behav Res Ctr, London, England
[3] Maastricht Univ, CAPHRI, Dept Hlth Educ & Hlth Promot, Maastricht, Netherlands
[4] Newcastle Univ, Inst Hlth & Soc, Newcastle Upon Tyne NE1 7RU, Tyne & Wear, England