Table 1.
Characteristics of the study population
| Primary knee replacement (n = 541) | Primary hip replacement (n = 468) | No primary joint replacement (n = 38,014) | |
| Age of entering the MCCS (years) | 60.3 ± 6.8 | 59.7 ± 7.1 | 54.8 ± 8.6 |
| Age of entering the JR cohort (years) | 68.1 ± 6.9 | 67.3 ± 7.2 | 62.6 ± 8.8 |
| Age on JR (years) | 70.7 ± 6.9 | 70.1 ± 7.2 | |
| Women, number (%) | 344 (63.6) | 283 (60.5) | 22,699 (59.7) |
| Height (cm) | 164.7 ± 9.9 | 165.7 ± 8.8 | 165.0 ± 9.3 |
| Weight (kg) | 80.7 ± 14.9 | 75.5 ± 13.2 | 73.1 ± 13.6 |
| Body mass index (kg/m2) | 29.8 ± 5.1 | 27.5 ± 4.3 | 26.8 ± 4.4 |
| Waist circumference (cm) | 91.7 ± 12.8 | 86.3 ± 12.7 | 85.1 ± 12.8 |
| Waist-to-hip ratio | 0.85 ± 0.09 | 0.84 ± 0.10 | 0.84 ± 0.09 |
| Fat mass (kg) | 32.3 ± 10.4 | 27.8 ± 9.1 | 26.0 ± 9.1 |
| Percentage fat (%) | 39.7 ± 8.6 | 36.5 ± 8.3 | 35.3 ± 8.6 |
| Country of birth, number (%) | |||
| Australia | 429 (79.3) | 383 (81.8) | 25,977 (68.3) |
| United Kingdom | 41 (7.6) | 32 (6.8) | 2,774 (7.3) |
| Italy | 45 (8.3) | 39 (8.3) | 4,999 (13.2) |
| Greece | 26 (4.8) | 14 (3.0) | 4,264 (11.2) |
| Education level, number (%) | |||
| Primary school | 85 (15.8) | 50 (10.7) | 7,107 (18.8) |
| Some high school | 255 (47.3) | 192 (41.2) | 14,422 (38.2) |
| Completed high school | 112 (20.8) | 102 (21.9) | 7,814 (20.7) |
| Degree/diploma | 87 (16.1) | 122 (26.2) | 8,426 (22.3) |
Data reported as the mean ± standard deviation, except where indicated. MCCS, Melbourne Collaborative Cohort Study; JR, joint replacement.