TY - JOUR
T1 - The effects of cash and lottery incentives on mailed surveys to physicians
T2 - A randomized trial
AU - Leung, Gabriel M.
AU - Ho, Lai Ming
AU - Chan, Moon Fai
AU - Johnston, Janice M.
AU - Wong, Fung Kam
N1 - Funding Information:
We thank Marie Chi for her expert secretarial assistance in the preparation of this manuscript. This study was funded through a Research Initiation Grant from the Committee of Research and Conference Grants at the University of Hong Kong.
PY - 2002/8/1
Y1 - 2002/8/1
N2 - Low response rates, especially among physicians, are a common problem in mailed survey research. We conducted a randomized trial to examine the effects of cash and lottery incentives on response rates. A total of 4,850 subjects were randomized to one of three interventions accompanying a mailed survey - no incentive (n = 1,700), cash payment [three levels of Hong Kong dollars (HKD) $10, $20, and $40; N = 50 in each subgroup], or entry into a lottery (three levels of HKD$1,000, $2,000, and $4,000; N = 1,000 in each subgroup) on receipt of the completed questionnaire. The response rates were higher among those offered incentives than those without (19.8% vs. 16.8%, P = .012). Cash was the more effective incentive compared to lottery (27.3% vs. 19.4%, P = .017). Response also increased substantially between the first and second mailings (14.2% vs. 18.8%, P > .001). In addition, those with specialist qualifications were more willing to participate in mailed surveys. We found no significant differences in response outcomes among the various incentive arms. Cash reward at the $20 level was the most cost-effective intervention, in terms of cost per responder. Further systematic examination of the effects of different incentive strategies in epidemiologic studies should be encouraged.
AB - Low response rates, especially among physicians, are a common problem in mailed survey research. We conducted a randomized trial to examine the effects of cash and lottery incentives on response rates. A total of 4,850 subjects were randomized to one of three interventions accompanying a mailed survey - no incentive (n = 1,700), cash payment [three levels of Hong Kong dollars (HKD) $10, $20, and $40; N = 50 in each subgroup], or entry into a lottery (three levels of HKD$1,000, $2,000, and $4,000; N = 1,000 in each subgroup) on receipt of the completed questionnaire. The response rates were higher among those offered incentives than those without (19.8% vs. 16.8%, P = .012). Cash was the more effective incentive compared to lottery (27.3% vs. 19.4%, P = .017). Response also increased substantially between the first and second mailings (14.2% vs. 18.8%, P > .001). In addition, those with specialist qualifications were more willing to participate in mailed surveys. We found no significant differences in response outcomes among the various incentive arms. Cash reward at the $20 level was the most cost-effective intervention, in terms of cost per responder. Further systematic examination of the effects of different incentive strategies in epidemiologic studies should be encouraged.
KW - Data collection
KW - Epidemiologic methods
KW - Incentives
KW - Motivation
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U2 - 10.1016/S0895-4356(02)00442-0
DO - 10.1016/S0895-4356(02)00442-0
M3 - Article
C2 - 12384195
AN - SCOPUS:0036697762
SN - 0895-4356
VL - 55
SP - 801
EP - 807
JO - Journal of Clinical Epidemiology
JF - Journal of Clinical Epidemiology
IS - 8
ER -