10 Details of ethics approval
The survey was approved by the local cantonal ethical committees of
Lucerne, Basel, Valais, and Zurich (reference numbers: 1008
[Luzern]; 37/11 [Basel]; CCVEM 015/11 [Valais]; 2012–0049
[Zürich]). Informed consent was obtained from all participants prior
to their participation in the survey.