The McMaster Optimal Aging Portal (the Portal) is a knowledge translation (KT) tool launched in 2014 to increase public access to trustworthy health information. Citizen-friendly content (blog posts, evidence summaries, web resource ratings) provide easy-to-read 'bottom line' messages appropriate for all audiences. Investigators would now like to know if and how KT strategies used to disseminate citizen-targeted information on cancer prevention impact knowledge, behavioural intentions and health behaviours of Canadian adults.