Baseline characteristics of the participants
| Characteristics | Participants with PDPS | Participants without PDPS | P value | ES |
| Participants, n (%) | 63 (72) | 24 (28) | n/a | n/a |
| Female, n (%) | 46 (73) | 15 (63) | 0.433 | Phi=0.10 |
| Age (years) | 22.0 (IQR 6.0) | 23.0 (IQR 9.3) | 0.242 | r=0.13 |
| BMI (kg/m2) | 23.5 (IQR 4.9) | 21.7 (IQR 4.0) | 0.207 | r=0.14 |
| Sport participation (h/week) | 3.0 (IQR 3.0) | 3.5 (IQR 1.9) | 0.466 | r=0.08 |
| Tegner Score (0–10) | 4.0 (IQR 3.0) | 5.0 (IQR 2.0) | 0.138 | r=0.16 |
| VAS-W (0–10) | 6.0 (IQR 3.0) | 5.0 (IQR 2.0) | 0.212 | r=0.13 |
| Bilateral PFP, n (%) | 45 (71) | 11 (46) | 0.044 | Phi=0.24 |
| Symptom duration (months) | 40.0 (IQR 64.0) | 20.0 (IQR 45.0) | 0.337 | r=0.07 |
| AKPS (0–100) | 74.0 (IQR 14.0) | 86.0 (IQR 11.5) | <0.001 | r=0.41 |
| Item 1 ‘limp’ (0–5) | 5.0 (IQR 2.0) | 5.0 (IQR 2.0) | 0.197 | r=0.14 |
| Item 2 ‘support’ (0–5) | 5.0 (IQR 2.0) | 5.0 (IQR 0.0) | 0.207 | r=0.014 |
| Item 3 ‘walking’ (0–5) | 3.0 (IQR 2.0) | 5.0 (IQR 2.0) | 0.004 | r=0.31 |
| Item 4 ‘stairs’ (0–10) | 8.0 (IQR 3.0) | 8.0 (IQR 5.0) | 0.992 | r=0.00 |
| Item 5 ‘squatting’ (0–5) | 4.0 (IQR 1.0) | 4.0 (IQR 1.0) | 0.009 | r=0.28 |
| Item 6 ‘running’ (0–10) | 6.0 (IQR 2.0) | 7.0 (IQR 2.0) | 0.286 | r=0.11 |
| Item 7 ‘jumping’ (0–10) | 7.0 (IQR 3.0) | 7.0 (IQR 3.0) | 0.090 | r=0.18 |
| Item 8 ‘prolonged sitting’ (0–10) | 6.0 (IQR 4.0) | 10.0 (IQR 0.0) | <0.001 | r=0.51 |
| Item 9 ‘pain’ (0–10) | 8.0 (IQR 5.0) | 8.0 (IQR 0.0) | 0.025 | r=0.24 |
| Item 10 ‘swelling’ (0–10) | 10.0 (IQR 2.0) | 10.0 (IQR 0.0) | 0.077 | r=0.19 |
| Item 11 ‘subluxations’ (0–10) | 10.0 (IQR 4.0) | 10.0 (IQR 0.0) | 0.128 | r=0.16 |
| Item 12 ‘atrophy’ (0–5) | 5.0 (IQR 0.0) | 5.0 (IQR 2.0) | 0.337 | r=0.10 |
| Item 13 ‘flexion deficiency’ (0–5) | 5.0 (IQR 0.0) | 5.0 (IQR 0.0) | 0.357 | r=0.10 |
| TSK (17–68) | 33.0 (IQR 8.0) | 33.0 (IQR 10.0) | 0.853 | r=0.20 |
Data are presented as numbers (percentages) and median (IQR 25%–75% (IQR)).
AKPS, Anterior Knee Pain Scale; BMI, body mass index; ES, effect size; h/week, hours per week; n, number; n/a, not applicable; PFP, patellofemoral pain; TSK, Tampa Scale for Kinesiophobia; VAS-W, Visual Analogue Scale for Worst pain.