Table 1

Sample, response, and response rates
Incentive group Control group
Sample 1 200 1 200
Sample after withdraws 1 161 1 145
Pre-reminder response 558 443
Pre-reminder response rate1 48.1% 38.7%
Reminder response 187 229
Reminder response rate1 187/603 = 31.0% 229/702 = 32.6%
Total response 745 672
Total response rate1 64.2% 58.7%

1 Response rate after withdraws.

Olsen et al.

Olsen et al. BMC Medical Research Methodology 2012 12:52   doi:10.1186/1471-2288-12-52

Open Data