Table I.
Patient characteristics of responders and non-responders
| Responders | Non-responders | p-value (chi-squared test) | |
|---|---|---|---|
| Number (%) | 1992 (87.4) | 286 (12.6) | |
| Female (n, %) | 1088 (54.6) | 165 (57.7) | 0.329 |
| Median age (yrs) (range)* | 68.8 (31 to 80) | 66.9 (32 to 80) | 0.004 (Student’s t-test) |
| Age group (n, %) | |||
| 30 to 49 years | 138 (6.9) | 35 (12.2) | 0.002 |
| 50 to 70 years | 955 (47.9) | 133 (46.5) | 0.649 |
| 71 to 80 years | 899 (45.1) | 118 (41.3) | 0.218 |
| Diagnosis (n, %)†‡ | |||
| Idiopathic osteoarthritis | 1598 (80.6) | 186 (65.3) | < 0.001 |
| Low-impact fractures | 116 (5.9) | 38 (13.3) | < 0.001 |
| Childhood diseases | 113 (5.7) | 16 (5.6) | 0.953 |
| Other arthritis | 53 (2.7) | 18 (6.3) | 0.001 |
| High-impact injuries | 20 (1.0) | 3 (1.1) | 0.945 |
| Atraumatic necrosis of femoral head | 62 (3.1) | 17 (6.0) | 0.015 |
| Other | 20 (1.0) | 7 (2.5) | 0.035 |
| Prostheses design (n, %)‡ | |||
| Uncemented | 1091 (55.0) | 154 (54.0) | 0.749 |
| Cemented | 433 (21.8) | 63 (22.1) | 0.921 |
| Hybrid | 458 (23.1) | 68 (23.9) | 0.779 |
* age of patients on date of dispatch of the patient-reported outcome measures † other arthritis (including rheumatoid arthritis, Bechterew’s disease), childhood diseases (congenital hip dislocation, Calvé-Legg-Perthes, epiphysiolysis, acetabular dysplasia), high-impact injuries (fracture of acetabulum, traumatic hip dislocation) and low-impact fractures (fresh fracture of proximal femur, late sequel from fracture of proximal femur) ‡ data on diagnosis and prosthesis design was only available for 1982 responders and 285 non-responders