Ethics approval would probably depend on not collecting identifying data like name, so it would be important to build that into your design. College name would work, but pseudo-randomising by leafleting some colleges would introduce significant confounding, because colleges frequently differ in their make up and culture.
Yes I mention the issues associated with college-based randomization in section 3.1.
Good point about not collecting identifying data, it should just be possible to ask for whatever information was used to decide who to leaflet, such as first letter of last name, which should avoid this issue.
Ethics approval would probably depend on not collecting identifying data like name, so it would be important to build that into your design. College name would work, but pseudo-randomising by leafleting some colleges would introduce significant confounding, because colleges frequently differ in their make up and culture.
Yes I mention the issues associated with college-based randomization in section 3.1.
Good point about not collecting identifying data, it should just be possible to ask for whatever information was used to decide who to leaflet, such as first letter of last name, which should avoid this issue.
Ah sorry, I missed that bit!