There was, however, a significant interaction effect between sex and invitation frame; attendance was higher in men invited using the loss-frame (89%) compared with the gain-frame (77%), and higher in women invited using the gain-frame (94%) compared with the loss-frame (68%).
After 1900 individuals had been invited using the recruitment process detailed above, a second invitation was sent out to give the non-responders another chance to participate and to increase the response rate.
Users can also share recipes they've "liked" via Facebook, as well as create "events" on Facebook, to which friends can be invited, using the menus assembled from Foodily searches.
Target populations were randomly invited using the National Population Registry.
Participating GPs had been invited using a purposive sampling strategy.
Initially, participants from two universities were invited using their official emails.
Trauma centres were invited using a standardised open letter sent by email.
Trial participation is invited using a highly secure automated online mail management system.
The first group of locums were invited using purposeful sampling and the second by a local association of locums.
