The investigators will conduct a cluster randomized controlled trial (RCT) in Facebook users (aged 50+) in Ontario. Randomization will be done at the level of the forward sortation area (FSA) - the first three characters of the postal code. All FSAs in Ontario will be randomized to one of six study arms - users assigned to each arm will receive one of the social media messages or no message (control). If users click on the message, a webpage with further information on screening will appear and participants will be asked to indicate intention to get screened for CRC. The primary outcome will be intention to screen and secondary outcomes will include other engagement metrics such as reach, cost-per-click, click-through rates, number of likes, number of impressions, and post comments.
This study will inform the feasibility of using social media for CRC screening and identify the most compelling CRC screening messages for the screen-eligible population.
