Table 3

Population, incentive and control group respondent characteristics
Variabels Population (aged 21–60) Pre-reminder Total
Mean p-value Mean p-value
Incentive group Control group Incentive vs control group Incentive group Control group incentive vs control group
Gender 1.51 1.44 1.39 0.174 1.47 1.43 0.160
Age 40.89 42.69 43.37 0.313 42.61 42.88 0.643
Education level2 0.23 0.15 0.10 0.024 0.15 0.11 0.015

1 Gender: 1 = woman, 2 = man. 2 Education level: 1 = primary school, 0 = other.

Olsen et al.

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

Open Data