| Intervention | Enhanced control | Control | P | |||
---|---|---|---|---|---|---|---|
n | % | n | % | n | % | ||
First e-mail (n = 6509) | |||||||
 Political party | |||||||
  Democrat | 1167 | 48.6 | 1062 | 45.3 | 788 | 44.6 | .02 |
  Republican | 1233 | 51.4 | 1281 | 54.7 | 978 | 55.4 | |
 Gender | |||||||
  Female | 789 | 32.9 | 687 | 29.3 | 517 | 29.3 | .01 |
  Male | 1610 | 67.1 | 1656 | 70.7 | 1248 | 70.7 | |
 Health background | |||||||
  Yes | 93 | 4.2 | 100 | 4.7 | 86 | 5.0 | .50 |
  No | 2098 | 95.8 | 2038 | 95.3 | 1622 | 95.0 | |
 Race/ethnicity | |||||||
  Non-Hispanic White | 1967 | 85.2 | 1788 | 80.9 | 1360 | 77.5 | <.0001 |
  Not non-Hispanic White | 341 | 14.8 | 422 | 19.1 | 394 | 22.5 | |
Second e-mail (n = 6153) | |||||||
 Party | |||||||
  Democrat | 1164 | 48.7 | 954 | 47.6 | 782 | 44.5 | .03 |
  Republican | 1227 | 51.3 | 1052 | 52.4 | 974 | 55.5 | |
 Gender | |||||||
  Female | 785 | 32.9 | 597 | 29.8 | 514 | 29.3 | .03 |
  Male | 1605 | 67.2 | 1409 | 70.2 | 1409 | 70.7 | |
 Health background | |||||||
  Yes | 93 | 4.3 | 87 | 4.8 | 84 | 5.0 | .57 |
  No | 2090 | 95.7 | 1744 | 95.2 | 1614 | 95.0 | |
 Race/ethnicity | |||||||
  Non-Hispanic White | 1962 | 85.3 | 1499 | 79.1 | 1353 | 77.6 | <.0001 |
  Not non-Hispanic White | 338 | 14.7 | 397 | 20.9 | 391 | 22.4 |