Table 1.
Demographic Information
| All Orders | Survey Responders | Non-responders | p-value | ||
|---|---|---|---|---|---|
| n (%) | n (%) | n (%) | |||
| Age | 0.008* | ||||
| 14-24 | 2,679 (33.5) | 2,412 (33.9) | 267 (30.2) | ||
| 25-29 | 2,406 (30.1) | 2,142 (30.1) | 264 (29.9) | ||
| 30-34 | 1,293 (16.2) | 1,149 (16.1) | 144 (16.3) | ||
| 35-39 | 894 (11.2) | 795 (11.2) | 99 (11.2) | ||
| 40+ | 735 (9.2) | 626 (8.8) | 109 (12.3) | ||
| Geographic Area | 0.050† | ||||
| South | 2,601 (32.5) | 2,328 (32.7) | 273 (30.9) | ||
| West | 1,985 (24.8) | 1,732 (24.3) | 253 (28.6) | ||
| Northeast | 1,780 (22.2) | 1,596 (22.4) | 184 (20.8) | ||
| Midwest | 1,644 (20.5) | 1,469 (20.6) | 175 (19.8) | ||
| Order year* | 0.000† | ||||
| 2011 | 653 (8.1) | 628 (8.8) | 25 (2.8) | ||
| 2012 | 1,206 (15.0) | 1,205 (16.9) | 1 (0.1) | ||
| 2013 | 1,923 (24.0) | 1,914 (26.8) | 9 (1.0) | ||
| 2014 | 1,847 (23.0) | 1,830 (25.7) | 17 (1.9) | ||
| 2015 | 2,390 (29.8) | 1,556 (21.8) | 834 (94.1) |
*
p-value from t-test of continuous age variable, by survey participation
†
p-value from chi-square test of association between variable and survey participation