Questionnaire No. 4

Prior to the 4th questionnaire

About 3 years separate the third from the fourth questionnaire. 

During these years the participants were sent a little something for their birthday. This allowed to check their contact information.  

The 4th questionnaire

This stage consisted in filling in another questionnaire online (a hard copy can be sent by post if wished) during about 45 - 60 minutes.

This questionnaire was very similar to the previous ones. It also was about the participants' socioprofessional and family background, their consumption of alcohol, cannabis and other drugs, as well as their personality and behavioral addictions like, for example, gambling.

The participation was rewarded with a gift voucher of CHF 50.-.

Participants were invited to fill in this questionnaire by email. In this email, they found a personal link to the online questionnaire. Those who prefered to fill in a hard copy could get it by post with a postage prepaid envelope.