Table 1.
Patient characteristics by date of admission relative to implementation of electronic health records (EHRs). Values are numbers (percentages) unless stated otherwise
| Characteristics | Study sample admissions | Control group admissions | |||||
|---|---|---|---|---|---|---|---|
| Pre-EHR | Post-EHR | P value* | Pre-EHR | Post-EHR | P value* | ||
| No of patients | 24 071 | 22 790 | 237 305 | 231 534 | |||
| No of admissions | 28 235 | 26 453 | 284 632 | 276 513 | |||
| Mean (SD) age (years) | 70.6 (14.7) | 70.6 (14.7) | 0.87 | 73.5 (13.4) | 73.8 (13.3) | <0.001 | |
| Mean (SD) length of stay (days) | 5.5 (6.6) | 5.5 (6.3) | 0.80 | 4.8 (5.1) | 4.8 (5.2) | 0.87 | |
| Female | 14 959 (53.0) | 14 162 (53.5) | 0.20 | 160 446 (56.5) | 157 926 (56.9) | 0.01 | |
| Race: | |||||||
| White | 21 325 (75.5) | 19 825 (74.9) | 0.19 | 239 418 (84.3) | 234 646 (84.5) | 0.15 | |
| Black | 5135 (18.2) | 4972 (18.8) | 32 306 (11.4) | 31 150 (11.2) | |||
| Other | 1775 (6.3) | 1656 (6.3) | 12 171 (4.3) | 11 850 (4.3) | |||
| Original reason for Medicare eligibility: | |||||||
| Age ≥65 | 17 263 (61.1) | 16 279 (61.5) | 0.80 | 198 713 (70.0) | 195 676 (70.5) | <0.001 | |
| Disability | 9604 (34.0) | 8899 (33.6) | 79 238 (27.9) | 76 352 (27.5) | |||
| End stage renal disease | 1368 (4.8) | 1275 (4.8) | 5944 (2.1) | 5618 (2.0) | |||
| Chronic illness†: | |||||||
| Alzheimer’s disease | 3953 (14.0) | 3835 (14.5) | 0.10 | 48 544 (17.1) | 47 557 (17.1) | 0.77 | |
| Ischemic heart disease | 11 530 (40.8) | 10 832 (40.9) | 0.80 | 115 210 (40.6) | 112 398 (40.5) | 0.45 | |
| Atrial fibrillation | 4368 (15.5) | 3983 (15.1) | 0.18 | 50 181 (17.7) | 48 931 (17.6) | 0.61 | |
| Congestive heart failure | 8745 (31.0) | 8325 (31.5) | 0.21 | 90 220 (31.8) | 88 724 (32.0) | 0.16 | |
| Chronic kidney disease | 9833 (34.8) | 9335 (35.3) | 0.26 | 94 645 (33.3) | 93 564 (33.7) | 0.004 | |
| Chronic obstructive pulmonary disease | 7031 (24.9) | 6476 (24.5) | 0.26 | 74 973 (26.4) | 73 176 (26.4) | 0.66 | |
| Diabetes mellitus | 8863 (31.4) | 8444 (31.9) | 0.19 | 85 270 (30.0) | 82 965 (29.9) | 0.21 | |
| Hyperlipidemia | 13 124 (46.5) | 12 462 (47.1) | 0.14 | 137 355 (48.4) | 133 630 (48.1) | 0.06 | |
| Hypertension | 17 426 (61.7) | 16 543 (62.5) | 0.05 | 182 369 (64.2) | 177 185 (63.8) | 0.001 | |
| Cancer‡ | 3283 (11.6) | 3003 (11.4) | 0.32 | 39 091 (13.8) | 37 839 (13.6) | 0.13 | |
Control hospitals were assigned the pre-implementation and post-implementation dates of study hospital in same hospital referral region, though they did not have a “go live” date.
*Estimated using two sample t tests or χ2 tests, as appropriate.
†Assessed using indicators from chronic condition warehouse file.
‡Includes presence of any of breast, endometrial, prostate, or colon cancer.