Table 2 Characteristics of survey responders compared to non-responders
|  | Responders (N = 3330) | Non-responders (N = 6225) | Standardized difference (CI) |
|---|---|---|---|
Site | |||
 A | 2152 (64.6) | 2641 (42.4) | 0.457 (0.414, 0.499) |
 B | 240 (7.2) | 679 (10.9)* | -0.129 (-0.171, -0.087) |
 C | 410 (12.3) | 1683 (27.0)†| -0.377 (-0.419, -0.334) |
 D | 528 (15.9) | 1222 (19.6)§ | -0.099 (-0.141, -0.057) |
Age, years | 73.5 (12.0) | 71.2 (14.8) | 0.177 (0.134, 0.219) |
 Unknown, n | 7 | 1 |  |
Male sex | 1845 (55.6) | 3355 (54.1) | 0.030 (-0.012, 0.072) |
 Unknown, n | 9 | 19 |  |
Non-white race | 106 (3.2) | 699 (11.5) | -0.320 (-0.363, -0.277) |
 Unknown, n | 44 | 130 |  |
Hispanic ethnicity | 34 (1.0) | 139 (2.3) | -0.097 (-0.139, -0.055) |
 Unknown, n | 34 | 83 |  |
Residence | |||
 Metropolitan/urban | 1628 (48.9) | 3171 (51.0) | -0.042 (-0.084, 0.000) |
 Micropolitan/large rural | 1079 (32.4) | 1811 (29.1) | 0.071 (0.029, 0.114) |
 Small town/small rural | 305 (9.2) | 595 (9.6) | -0.014 (-0.056, 0.028) |
 Rural/isolated rural | 317 (9.5) | 642 (10.3) | -0.027 (-0.069, 0.015) |
 Unknown, n | 1 | 6 |  |
Body mass index, kg/m2 | |||
 <25 | 443 (15.3) | 978 (19.6) | -0.115 (-0.161, -0.069) |
 25 to < 30 | 837 (28.8) | 1372 (27.5) | 0.029 (-0.017, 0.075) |
 ≥30 | 1625 (55.9) | 2637 (52.9) | 0.062 (0.016, 0.107) |
 Unknown, n | 425 | 1238 |  |
Smoking status | |||
 Current | 230 (8.8) | 855 (17.5) | -0.262 (-0.309, -0.214) |
 Former | 1105 (42.1) | 2082 (42.7) | -0.012 (-0.059, 0.036) |
 Never | 1288 (49.1) | 1928 (39.8) | 0.189 (0.141, 0.237) |
 Unknown, n | 707 | 1350 |  |
Ejection fraction, % | |||
 <40 | 441 (21.7) | 823 (27.3) | -0.129 (-0.186, -0.073) |
 40–49 | 407 (20.0) | 494 (16.4) | 0.095 (0.039, 0.151) |
 ≥50 | 1183 (58.3) | 1701 (56.4) | 0.038 (-0.018, 0.094) |
 Unknown, n | 1299 | 3207 |  |
Hypertension | 2354 (70.7) | 3542 (56.9) | 0.290 (0.247, 0.332) |
Coronary artery disease | 1537 (46.2) | 2090 (33.6) | 0.259 (0.217, 0.301) |
Cardiac arrhythmias | 2063 (62.0) | 2816 (45.2) | 0.340 (0.298, 0.382) |
Hyperlipidemia | 2043 (61.4) | 2799 (45.0) | 0.333 (0.291, 0.375) |
Stroke | 354 (10.6) | 540 (8.7) | 0.066 (0.024, 0.108) |
Arthritis | 1097 (32.9) | 1458 (23.4) | 0.213 (0.171, 0.255) |
Asthma | 265 (8.0) | 362 (5.8) | 0.085 (0.043, 0.127) |
Cancer | 802 (24.1) | 936 (15.0) | 0.230 (0.187, 0.272) |
Chronic kidney disease | 832 (25.0) | 1372 (22.0) | 0.070 (0.027, 0.112) |
Chronic obstructive pulmonary disease | 508 (15.3) | 773 (12.4) | 0.082 (0.040, 0.124) |
Dementia | 79 (2.4) | 392 (6.3) | -0.194 (-0.236, -0.151) |
Depression | 462 (13.9) | 761 (12.2) | 0.050 (0.007, 0.091) |
Diabetes | 1131 (34.0) | 1538 (24.7) | 0.204 (0.162, 0.247) |
Hepatitis | 27 (0.8) | 63 (1.0) | -0.021 (-0.063, 0.021) |
Osteoporosis | 227 (6.8) | 357 (5.7) | 0.045 (0.003, 0.087) |
Schizophrenia | 18 (0.5) | 74 (1.2) | -0.070 (-0.112, -0.028) |
Substance abuse disorders | 151 (4.5) | 349 (5.6) | -0.049 (-0.091, -0.007) |
Anxiety | 272 (8.2) | 523 (8.4) | -0.009 (-0.051, 0.034) |