Table 3.
Characteristics of the Dutch OKS-APQ
| Items | Item-Total Correlation (pooled sample) | Missing, n (%) (pooled sample) | Floor, n (%) (preoperative sample) | Ceiling, n (%) (preoperative sample) | Floor, n (%) (postoperative sample) | Ceiling, n (%) (postoperative sample) |
|---|---|---|---|---|---|---|
| It is a problem for me to do activities (e.g. sports, dancing, walking) to the level I want, because of my knee | 0.84 | 0 (0.0%) | 64 (89%) | 1 (1.4%) | 19 (32.2%) | 7 (11.9%) |
| It is a problem for me to carry heavy things (e.g. items at work, shopping or a child), because of my knee | 0.83 | 0 (0.0%) | 41 (56.9%) | 1 (1.4%) | 12 (20.3%) | 15 (25.4%) |
| I need to modify my work or everyday activities, because of my knee | 0.92 | 4 (3.1%) | 42 (60%) | 3 (4.3%) | 11 (19.3%) | 18 (31.6%) |
| I need to plan carefully before going out for the day because of my knee (e.g. taking painkillers, using a knee brace or checking that there will be places to sit down) | 0.89 | 0 (0.0%) | 44 (61.1%) | 2 (2.8%) | 9 (15.3%) | 27 (45.8%) |
| It is a problem for me to fully take part in activities with friends and family, because of my knee | 0.85 | 0 (0.0%) | 34 (47.2%) | 1 (1.4%) | 11 (18.6%) | 18 (30.5%) |
| It is a problem for me to walk at the pace I would like, because of my knee | 0.88 | 0 (0.0%) | 62 (86.1%) | 10 (13.9%) | 16 (27.1%) | 12 (20.3%) |
| It is a problem for me to twist or turn, as my knee may give way or be painful | 0.87 | 0 (0.0%) | 46 (63.9%) | 3 (4.2%) | 10 (17%) | 23 (39%) |
| It is a problem for me that I need to take longer to do everyday activities, because of my knee | 0.88 | 1 (0.8%) | 29 (40.9%) | 8 (11.3%) | 7 (12.1%) | 18 (31%) |