Three behavior change theory–informed randomized studies within a trial to improve response rates to trial postal questionnaires
IQuaD was funded by the NIHR HTA (project 09/01/45). INTERVAL was funded by the NIHR HTA (project 06/35/99). No additional funding was obtained to conduct the randomised studies with the trials. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health. The Health Services Research Unit is funded by the Chief Scientist Office of the Scottish Government Health and Social Care Directorates. ; Peer reviewed ; Postprint