(b).
| MSSA | MRSA | Noncarrier | p | |
|---|---|---|---|---|
| n (%) | 798 (20.3%) | 177 (4.5%) | 2,952 (75.2%) | |
| Mean age (SD) | 62.3 (11.4) | 63.8 (11.5) | 64.2 (10.9) | <0.01 |
| Gender, n (%) | <0.01 | |||
| Female | 423 (53%) | 99 (56%) | 1,801 (61%) | |
| Male | 375 (47%) | 78 (44%) | 1,151 (39%) | |
| Joint, n (%) | 0.14 | |||
| Hips | 351 (44%) | 76 (43%) | 1,181 (40%) | |
| Knees | 447 (56%) | 101 (57%) | 1,771 (60%) | |
| Mean Charlson Comorbidity Index (SD) | 3.3 (1.7) | 3.6 (1.8) | 3.5 (1.6) | <0.01 |
| Mean body mass index (SD) | 32.4 (7.3) | 32.9 (8.0) | 31.8 (7.1) | 0.02 |
| Previous inpatient stay | ||||
| 0-1 month, n (%) | 32 (4%) | 7 (4%) | 148 (5%) | 0.72 |
| 1-2 months, n (%) | 72 (9%) | 23 (13%) | 295 (10%) | 0.27 |
| 2-3 months, n (%) | 112 (14%) | 41 (23%) | 413 (14%) | 0.01 |
| 3–6 months, n (%) | 200 (25%) | 67 (38%) | 768 (26%) | <0.01 |
| 6–12 months, n (%) | 319 (40%) | 97 (55%) | 1,210 (41%) | <0.01 |
MSSA: methicillin-sensitive Staphylococcus aureus; MRSA: methicillin-resistant Staphylococcus aureus.