Table 1. Descriptive Statistics of Medicare Beneficiaries With Rheumatoid Arthritis or Osteoarthritis Residing in Metropolitan Statistical Areas (MSAs) With or Without the Comprehensive Care for Joint Replacement (CJR) Model, 2013.
| Variable | MSAs without CJR model | MSAs with CJR model | Total | P valuea |
|---|---|---|---|---|
| No. of patientsb | 2 421 848 (54.5) | 2 025 357 (45.5) | 4 447 205 | |
| Age, mean (SD), y | 76.98 (7.91) | 77.43 (7.99) | 77.18 (7.95) | <.001 |
| Sex | ||||
| Female, No. (%) | 1 599 361 (66.0) | 1 351 779 (66.7) | 2 951 140 (66.4) | <.001 |
| Male, No. (%) | 822 487 (34.0) | 673 578 (33.3) | 1 496 065 (33.6) | |
| Race/ethnicity, No. (%) | ||||
| Non-Hispanic White | 2 152 536 (88.9) | 1 775 896 (87.7) | 3 928 432 (88.3) | <.001 |
| Non-Hispanic Black | 232 064 (9.6) | 174 683 (8.6) | 406 747 (9.2) | |
| Hispanic | 37 248 (1.5) | 74 778 (3.7) | 112 026 (2.5) | |
| Dual eligibility for Medicaid and Medicare, No. (%) | 306 429 (12.7) | 350 644 (17.3) | 657 073 (14.8) | <.001 |
| Race/ethnicity by dual eligibility, No. (%) | ||||
| Non-Hispanic White NDE beneficiaries | 1 947 596 (80.4) | 1 550 369 (76.6) | 3 497 965 (78.7) | <.001 |
| Non-Hispanic White DE beneficiaries | 204 940 (8.5) | 225 527 (11.1) | 430 467 (9.7) | |
| Non-Hispanic Black NDE beneficiaries | 154 508 (6.4) | 110 898 (5.5) | 265 406 (5.97) | |
| Non-Hispanic Black DE beneficiaries | 77 556 (3.2) | 63 785 (3.2) | 141 341 (3.2) | |
| Hispanic NDE beneficiaries | 13 315 (0.6) | 13 446 (0.7) | 26 761 (0.6) | |
| Hispanic DE beneficiaries | 23 933 (1.0) | 61 332 (3.0) | 85 265 (1.9) | |
| No. of chronic conditions by race/ethnicity, mean (SD)c | ||||
| Non-Hispanic White | 4.37 (2.59) | 4.59 (2.66) | 4.47 (2.63) | <.001 |
| Non-Hispanic Black | 4.94 (2.65) | 4.92 (2.66) | 4.94 (2.66) | .01 |
| Hispanic | 4.74 (2.70) | 5.52 (2.72) | 5.26 (2.74) | <.001 |
| No. of chronic conditions by dual eligibility, mean (SD)c | ||||
| Non–dual eligibility | 4.26 (2.54) | 4.39 (2.58) | 4.32 (2.56) | <.001 |
| Dual eligibility | 5.55 (2.76) | 5.90 (2.76) | 5.74 (2.76) | <.001 |
| Type of surgery, No. (%)d | ||||
| THR | 25 682 (1.1) | 20 425 (1.0) | 46 107 (1.0) | <.001 |
| TKR | 53 977 (2.2) | 40 574 (2.0) | 94 551 (2.1) | <.001 |
| MSAse | ||||
| No. | 104 | 67 | 171 | |
| Total population in 1000s, median (IQR) | 439 (223-961) | 467 (234-1757) | 446 (225-1134) | .56 |
| % of Population >65 y, mean (SD) | 15.26 (4.83) | 14.46 (3.87) | 14.94 (4.48) | .27 |
| % of Females, mean (SD) | 50.81 (0.85) | 51.01 (0.82) | 50.89 (0.84) | .14 |
| % of High school graduates, mean (SD) | 87.79 (4.22) | 88.01 (3.61) | 87.88 (3.98) | .96 |
| Income, mean (SD), $ | 68 675 (12 787) | 69 275 (11 479) | 68 912 (12 257) | .66 |
Abbreviations: DE, dual-eligible; IQR, interquartile range; NDE, non–dual eligible; THR, total hip replacement; TKR, total knee replacement.
a
P values were calculated with Kruskal-Wallis tests (for continuous variables) or χ2 tests (for categorical variables). Kruskal-Wallis and χ2 tested for the differences in the distribution of characteristics across MSAs with vs without the CJR model.
b
Data were from the 2013 Medicare Master Beneficiary Summary File–Base Segment and Chronic Conditions Segment.
c
Mean of 24 chronic conditions included in the Medicare Master Beneficiary Summary File–Chronic Conditions Segment.
d
Data were from the 2013 Medicare Provider Analysis and Review file.
e
Data were from the American Community Survey File.