TABLE 1.
Descriptive statistics for elective admissions
| Variables | Prepolicy periods | Postpolicy periods | ||||||
|---|---|---|---|---|---|---|---|---|
| (1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | |
| All admissions | CJR | Non‐CJR | p value | All admissions | CJR | Non‐CJR | p value | |
| Total 90‐day episode costs | $24,717 | $25,492 | $24,150 | <0.001 | $21,430 | $21,659 | $21,271 | <0.001 |
| SNF 90‐day costs | $3445 | $3663 | $3285 | <0.001 | $2117 | $2089 | $2137 | <0.001 |
| Inpatient costs (index procedures) | $13,324 | $13,589 | $13,130 | <0.001 | $12,352 | $12,540 | $12,220 | 0.039 |
| Outpatient 90‐day costs | $635 | $624 | $643 | <0.001 | $657 | $651 | $662 | 0.097 |
| Durable medical equipment | $124 | $128 | $120 | <0.001 | $92 | $91 | $92 | 0.759 |
| Home health agency | $2195 | $2242 | $2160 | <0.001 | $2042 | $2122 | $1986 | <0.001 |
| BPCI inpatient 90‐day costs | $1034 | $1070 | $1007 | <0.001 | $961 | $989 | $940 | 0.038 |
| BPCI Part B 90‐day costs | $2983 | $3040 | $2941 | <0.001 | $2748 | $2793 | $2717 | <0.001 |
| Length of stay (days) | 3.67 | 3.66 | 3.68 | 0.180 | 3.31 | 3.17 | 3.41 | <0.001 |
| Number of episode a | 361 | 326 | 385 | <0.001 | 380 | 328 | 416 | <0.001 |
| Mortality (30 days) | 0.23% | 0.25% | 0.22% | 0.045 | 0.20% | 0.20% | 0.19% | 0.869 |
| Mortality (90 days) | 0.48% | 0.50% | 0.47% | 0.130 | 0.40% | 0.40% | 0.40% | 0.870 |
| 90‐day readmission (any reasons) | 9.74% | 9.69% | 9.77% | 0.330 | 9.29% | 9.10% | 9.42% | 0.010 |
| PE | 2.43% | 2.34% | 2.49% | 0.001 | 2.04% | 1.97% | 2.09% | 0.060 |
| DVT | 5.01% | 5.01% | 5.01% | 0.975 | 4.50% | 4.51% | 4.49% | 0.762 |
| Age | 74.08 | 74.17 | 74.02 | <0.001 | 73.71 | 73.75 | 73.69 | 0.023 |
| Female | 62.82% | 63.16% | 62.58% | <0.001 | 61.99% | 62.37% | 61.73% | 0.002 |
| White | 91.19% | 90.54% | 91.66% | <0.001 | 90.32% | 89.79% | 90.70% | <0.001 |
| Black | 4.78% | 4.83% | 4.74% | 0.184 | 4.70% | 4.58% | 4.78% | 0.026 |
| Disabled | 0.70% | 0.68% | 0.71% | 0.445 | 0.63% | 0.61% | 0.65% | 0.349 |
| CCI of 0 | 55.4% | 55.4% | 55.3% | 0.553 | 55.5% | 55.0% | 55.9% | <0.001 |
| CCI of 1 | 26.7% | 26.5% | 26.8% | 0.024 | 25.4% | 25.5% | 25.3% | 0.170 |
| CCI of 2 or higher | 17.9% | 18.1% | 17.9% | 0.067 | 19.1% | 19.4% | 18.9% | <0.001 |
| Age 65–69 years | 28.8% | 28.5% | 29.0% | <0.001 | 30.4% | 30.4% | 30.4% | 0.713 |
| Age 70–74 years | 28.4% | 28.1% | 28.6% | <0.001 | 29.5% | 29.1% | 29.8% | <0.001 |
| Age 75–79 years | 22.1% | 22.3% | 22.0% | 0.038 | 21.6% | 21.7% | 21.5% | 0.425 |
| Age 80–84 years | 13.6% | 13.9% | 13.4% | <0.001 | 12.3% | 12.6% | 12.1% | 0.002 |
| Age 85 years or older | 7.1% | 7.2% | 6.9% | <0.001 | 6.2% | 6.3% | 6.2% | 0.554 |
| Dual eligibility | 6.5% | 7.3% | 6.0% | <0.001 | 5.9% | 6.7% | 5.3% | <0.001 |
| DRG 469 | 2.5% | 2.7% | 2.4% | <0.001 | 2.2% | 2.3% | 2.0% | <0.001 |
| DRG 470 | 97.5% | 97.3% | 97.6% | <0.001 | 97.8% | 97.7% | 98.0% | <0.001 |
| N | 471,651 | 199,251 | 272,400 | 222,624 | 91,554 | 131,070 | ||
Note: Only prepolicy periods included (January 2013–June 2015). Cost variables were adjusted for inflation (2017 dollar value). DRG 469 represents major joint replacement with major complication and DRG 470 represents major joint replacement without major complication.
Abbreviations: BPCI, bundled payment for care improvement; CCI, Charlson Comorbidity Index; CJR, Comprehensive Care for Joint Replacement; DRG, diagnosis‐related group; DVT, deep vein thrombosis; PE, pulmonary embolism; SNF, skilled nursing facilities.
a
The mean volume in each prepolicy and postpolicy was calculated using an identical length of time and accounted for seasonality.