[1] Department of Social Medicine,
[2] Faculty of Medicine,undefined
[3] Vrije Universiteit,undefined
[4] van der Boechorstraat 7–9,undefined
[5] 1081 BT Amsterdam,undefined
[6] The Netherlands,undefined
[7] Institute for Research in Extramural Medicine,undefined
[8] Faculty of Medicine,undefined
[9] Vrije Universiteit,undefined
[10] van der Boechorstraat 7–9,undefined
[11] 1081 BT Amsterdam,undefined
[12] The Netherlands,undefined