%0 Journal Article
%T The effect of a monetary incentive on return of a postal health and development questionnaire: a randomised trial [ISRCTN53994660]
%A Sara Kenyon
%A Katie Pike
%A David Jones
%A David Taylor
%A Alison Salt
%A Neil Marlow
%A Peter Brocklehurst
%J BMC Health Services Research
%D 2005
%I BioMed Central
%R 10.1186/1472-6963-5-55
%X The MRC ORACLE Children Study is assessing the health and development of nearly 9000 seven year old children whose mothers' joined the MRC ORACLE Trial. We carried out a randomised controlled trial of inclusion of monetary incentive (five pound voucher redeemable at many high street stores) with the reminder questionnaire to parents. This trial took place between April 2002 and November 2003. When the parents were sent the reminder questionnaire about their child's health and development they were randomly assigned by concealed computer-generated allocation stratified by week of birthday to receive a five pound voucher or no incentive. The population were 722 non-responders to the initial mailing of a 12-page questionnaire. Main outcome measures: Difference in response rate between the two groups.Inclusion of the voucher with the reminder questionnaire resulted in a 11.7%(95% CI 4.7% to 18.6%) improvement in the response rate between the two groups.This improvement in response rate and hence the validity and reliability of results obtained appears to be justified ethically and financially.Postal questionnaires are widely used to collect data in health research, but a poor response rate may reduce the validity and reliability of results. In a systematic review of randomised controlled trials of strategies to improve the response rate to postal questionnaires[1], a monetary reward had a significant effect on response. However, caution was attached to the interpretation of the findings in this review [2]. On further examination of the updated review 20% of the participants included in the analysis of the effect of inclusion of a monetary incentive in the final response came from healthcare settings [3] and none of the studies evaluated the use of monetary incentives for a postal questionnaire to collect data from a follow-up of a clinical trial. To evaluate the impact of such an intervention on response rate in such a setting we undertook a randomised trial.The MRC ORA
%U http://www.biomedcentral.com/1472-6963/5/55