Short report: encouraging GPs to complete postal questionnaires--one big prize or many small prizes? A randomized controlled trial.
BACKGROUND
Low response rates to surveys are a problem in general practice. There is evidence that offering GPs incentives improves response rates to postal questionnaires. However, there is less evidence about the most effective form of incentive.


OBJECTIVE
Our trial aimed to maximize response to a postal questionnaire and to test the most effective form of incentive.


METHODS
The study involved a randomized controlled trial of a postal survey


RESULTS
The incentive of a lottery for six bottles of champagne generated a response rate of 79%. Furthermore, one chance of six bottles generated 9% more responses than six chances of one bottle.


CONCLUSIONS
This study has established that, among incentives for postal questionnaires, one big prize improves the yield more than many small prizes despite the lower odds of winning. It has also confirmed that offering a modest incentive to GPs generates good response rates for postal questionnaires.
Thomson
C E
CE
Faculty of Health and Social Sciences, Queen Margaret University College, Edinburgh,UK. cthompson@qmuc.ac.uk
Paterson-Brown
S
S
Russell
D
D
McCaldin
D
D
Russell
I T
IT
D001291:Attitude of Health Personnel; D015982:Bias; D019538:Health Care Surveys; D006801:Humans; D009042:Motivation; D010816:Physician Incentive Plans / Q000191:economics; D010821:Physicians, Family / Q000523:psychology*; D011177:Postal Service; D013222:State Medicine; D011795:Surveys and Questionnaires / Q000706:statistics & numerical data*; D014040:Token Economy; D006113:United Kingdom