Table 2. Medicare Expenditure and Perioperative and Postoperative Characteristics for Low Users and Super-Utilizers in the Crude Population and the Propensity-Matched Population.
| Variable | Median (IQR) Expenditures | |||||||
|---|---|---|---|---|---|---|---|---|
| Crude Population | Propensity-Matched Population | |||||||
| Total (n = 626 754) | Low User (n = 547 008) | Super-Utilizer (n = 79 746) | Effect Size | Total (n = 52 986) | Low User (n = 35 497) | Super-Utilizer (n = 17 489) | Effect Size | |
| Preoperative outcome | ||||||||
| Sum expenditure, $ million | 3303 | 1961 | 1342 | NA | 465 | 230 | 235 | NA |
| Expenditure per patient, $ thousand | 1.3 (0.4-4.2) | 1.1 (0.3-3.2) | 6.6 (1.8-21.0) | −2.490 | 2.6 (0.8-8.7) | 2.1 (0.7-6.6) | 4.0 (1.1-15.1) | −2.363 |
| Operative outcomes | ||||||||
| Expenditure per patient, $ thousand | 12.7 (11.4-14.9) | 12.4 (11.2-13.9) | 37.4 (20.9-58.9) | −6.016 | 13.5 (11.7-17.0) | 12.9 (11.3-15.3) | 16.0 (12.8-25.6) | −3.926 |
| Length of staya | 3 (2-4) | 3 (2-3) | 11 (6-19) | −0.104 | 4 (3-6) | 4 (3-6) | 4 (3-7) | −0.012 |
| Postoperative outcome | ||||||||
| Sum expenditure, $ million | 7548 | 1016 | 6532 | NA | 1693 | 134 | 1558 | NA |
| Expenditure per patient, $ thousand | 1.3 (0.4-3.8) | 1.1 (0.4-2.4) | 72.8 (52.2-100.1) | −12.179 | 6.2 (1.6-68.1) | 3.0 (0.9-6.3) | 79.7 (68.5-101.1) | −23.782 |
| Complications within 90 d, No. (IQR)a | 0 (0-0) | 0 (0-0) | 2 (1-3) | −0.050 | 0 (0-1) | 0 (0-1) | 0 (0-1) | −0.009 |
| Readmission, No. (%) | ||||||||
| 90 d | 76 376 (12.2) | 16 921 (3.1) | 59 455 (74.6) | 0.728 | 21 383 (40.4) | 12 833 (36.2) | 8550 (48.9) | 0.122 |
| 30 d | 37 447 (6.0) | 10 140 (1.9) | 27 307 (34.2) | 0.455 | 11 464 (21.6) | 7953 (22.4) | 3511 (20.1) | 0.027 |
| Mortality, No. (%) | ||||||||
| 90 d | 9980 (1.6) | 1739 (0.3) | 8241 (10.3) | 0.267 | 1144 (2.2) | 681 (1.9) | 463 (2.6) | 0.024 |
| 30 d | 2942 (0.5) | 805 (0.1) | 2137 (2.7) | 0.123 | 424 (0.8) | 287 (0.8) | 137 (0.8) | 0.001 |
Abbreviations: IQR, interquartile range; NA, not applicable.
a
Used in the propensity-matching analysis.