Table 1:
Comparison of Model Parameters in Retrospective and Prospective Validation Data sets
| Variables | Retrospective Validation | Prospective Validation | |||||||
|---|---|---|---|---|---|---|---|---|---|
| N(%) | Readmit (%) | N(%) | Readmit (%) | ||||||
| History with MGH (past year) | |||||||||
| None | 3,583 | (38%) | 221 | 6.2% | 1,347 | (42%) | 75 | 5.6% | |
| Outpatient Only | 2,554 | (27%) | 221 | 8.7% | 693 | (22%) | 53 | 7.6% | |
| Prior Admission | 3,210 | (34%) | 666 | 20.7% | 1,134 | (36%) | 165 | 14.6% | |
| Admission Source | |||||||||
| Physician | 4,345 | (46%) | 355 | 8.2% | 1,431 | (45%) | 96 | 6.7% | |
| Transfer | 1,266 | (14%) | 135 | 10.7% | 450 | (14%) | 48 | 10.7% | |
| Other | 1,942 | (21%) | 294 | 15.1% | 675 | (21%) | 76 | 11.3% | |
| Emergency Med Svc. | 1,582 | (17%) | 276 | 17.4% | 565 | (18%) | 68 | 12.0% | |
| SNF or Rehab | 212 | (2%) | 48 | 22.6% | 53 | (2%) | 5 | 9.4% | |
| Admission Type | |||||||||
| Planned | 2,578 | (28%) | 181 | 7.0% | 821 | (26%) | 46 | 5.6% | |
| Unplanned | 6,769 | (72%) | 927 | 13.7% | 2,353 | (74%) | 247 | 10.5% | |
| Behavioral Issue (Past Year) | |||||||||
| No | 9,009 | (96%) | 1,027 | 11.4% | 3,025 | (95%) | 274 | 9.1% | |
| Yes | 338 | (4%) | 81 | 24.0% | 149 | (5%) | 19 | 12.8% | |
| Elixhauser Comorbidity Count (past year data) | |||||||||
| 0 | 3,949 | (42%) | 272 | 6.9% | 1,517 | (48%) | 86 | 5.7% | |
| 1 | 1,290 | (14%) | 111 | 8.6% | 357 | (11%) | 31 | 8.7% | |
| 2 | 948 | (10%) | 94 | 9.9% | 295 | (9%) | 27 | 9.2% | |
| 3 | 759 | (8%) | 109 | 14.4% | 222 | (7%) | 24 | 10.8% | |
| 4 | 619 | (7%) | 119 | 19.2% | 190 | (6%) | 20 | 10.5% | |
| 5 | 483 | (5%) | 87 | 18.0% | 154 | (5%) | 22 | 14.3% | |
| 6 | 393 | (4%) | 71 | 18.1% | 128 | (4%) | 25 | 19.5% | |
| 7 | 324 | (3%) | 79 | 24.4% | 86 | (3%) | 18 | 20.9% | |
| 8+ | 582 | (6%) | 166 | 28.5% | 225 | (7%) | 40 | 17.8% | |
| Inpatient Bed Days (past year) | |||||||||
| 0 | 6,137 | (66%) | 442 | 7.2% | 2,040 | (64%) | 128 | 6.3% | |
| 1–5 | 862 | (9%) | 122 | 14.2% | 395 | (12%) | 35 | 8.9% | |
| 6–10 | 719 | (8%) | 134 | 18.6% | 241 | (8%) | 32 | 13.3% | |
| 10–20 | 721 | (8%) | 154 | 21.4% | 229 | (7%) | 45 | 19.7% | |
| 20+ | 908 | (10%) | 256 | 28.2% | 269 | (8%) | 53 | 19.7% | |
| Insulin | |||||||||
| No | 6,951 | (74%) | 719 | 10.3% | 2,423 | (76%) | 188 | 7.8% | |
| Yes | 2,396 | (26%) | 389 | 16.2% | 751 | (24%) | 105 | 14.0% | |
| Antipsychotic | |||||||||
| No | 7,854 | (84%) | 877 | 11.2% | 2,399 | (76%) | 218 | 9.1% | |
| Yes | 1,493 | (16%) | 231 | 15.5% | 775 | (24%) | 75 | 9.7% | |
| Other Medication | |||||||||
| No | 7,830 | (84%) | 812 | 10.4% | 2,798 | (88%) | 238 | 8.5% | |
| Yes | 1,517 | (16%) | 296 | 19.5% | 376 | (12%) | 55 | 14.6% | |