The check your cannabis screener: a new online personalized feedback tool.

This brief report describes the development and first year of use of an Internet-based screener for Cannabis users. Two versions of the Check Your Cannabis screener were compared, one linked to an already established harm reduction website for young Cannabis users (as an exercise called "Check how I compare with others," on www.WhatsWithWeed.ca) and the other a standalone version (www.CheckYourCannabis.net). The What's With Weed version attracted ten times more users and had a significantly younger audience as compared to the standalone version, underlining the benefits of targeting a website to a specific audience and linking to websites with already established reputations. Further work is needed to establish any impact on actual Cannabis use from taking the Check Your Cannabis screener.