2,872
Participants
Start Date
November 15, 2016
Primary Completion Date
February 15, 2017
Study Completion Date
February 25, 2019
Group 1 information
Group 1 prize draw information for participants to win 100% of an Amazon gift card (or currency equivalent) in invitation letter.
Group 2 information
Group 2 prize draw information for participants to win 75% of an Amazon gift card (or currency equivalent) in invitation letter.
Group 3 information
Group 3 prize draw information for participants to win 50% of an Amazon gift card (or currency equivalent) in invitation letter.
Group 4 information
Group 4 prize draw information for participants to win 25% of an Amazon gift card (or currency equivalent) in invitation letter.
Group 5 no information
Group 5 no Information for participants to enter a draw to win an Amazon gift card (or currency equivalent) in invitation letter.
Group A Reminder
One survey reminder at 14 days
Group B Reminders
Two survey reminders one at 14 days and one at 28 days
ThinkWell, Oxford
The BMJ
OTHER
University of Oxford
OTHER
Queen's University, Belfast
OTHER
ThinkWell
OTHER