Prognostic factors for pain severity† at 3 and 12 months
| 3 months | 12 months | |||
|---|---|---|---|---|
| Variables | β (95%CI) | p Value | β (95% CI) | p Value |
| Age | ||||
| Gender | ||||
| Body mass index | ||||
| Duration of complaints (ref = 1–2 months) | ||||
| 2–6 months | 22.95 (13.53 to 32.36) | <0.001 | ||
| 6–12 months | 12.33 (3.56 to 21.09) | 0.006 | 21.88 (11.60 to 32.15) | <0.001 |
| 12+ months | 11.36 (3.96 to 18.77) | 0.003 | 24.94 (15.78 to 34.11) | <0.001 |
| Allocated preferred treatment (ref = no preference) | ||||
| Not allocated | ||||
| Allocated | ||||
| Recruitment | −17.50 (−25.85 to −9.15) | <0.001 | ||
| Bilaterality | ||||
| Work type (ref=not employed) | ||||
| Sedentary | ||||
| Active | ||||
| Sport | ||||
| Baseline usual/rest pain | ||||
| Baseline worse/on activity pain | 0.45 (0.28 to 0.62) | <0.001 | 0.29 (0.11 to 0.46) | 0.001 |
| Anterior Knee Pain Scale | −0.33 (−0.59 to −0.06) | 0.015 | −0.45 (−0.72 to −0.18) | 0.001 |
| Functional Index Questionnaire | ||||
| R2 | 0.260 | 0.237 | ||
| AUC (cut-off pain at follow-up 40) | 0.534 | 0.631 | ||
| AUC (cut-off pain at follow-up 60) | 0.790 | 0.736 | ||
| AUC (cut-off pain at follow-up 80) | 0.915 | 0.869 | ||
†Measured as worst or activity-related pain on a visual analogue scale; variable ‘treatment’ not presented, but was included in final models (significant in 3-month and 12-month model).
Backward selection: p(IN)=0.05, p(OUT)=0.10.