Demographics table for participants
| Measure | Control (n=37) | Parkinson’s disease (n=100) | P value |
| Gender (M:F) | 16:21 | 52:48 | ns |
| Age (years) | 66.1 (9.4) | 64.5 (7.7) | ns |
| Years of education | 17.18 (2.35) | 17.04 (2.84) | ns |
| MoCA score (out of 30) | 28.6 (1.4) | 28.0 (2.0) | ns |
| Cats-and-Dogs score | 2.10 (0.58) | 1.91 (0.55) | ns |
| Biological motion score | 14.68 (9.65) | 16.46 (11.49) | ns |
| UPDRS-III | 5.5 (4.7) | 18.9 (13.3) | *** |
| Pelli-Robson contrast sensitivity | 1.81 (0.22) | 1.80 (0.16) | ns |
| Binocular LogMAR visual acuity | −0.08 (0.23) | −0.09 (0.13) | ns |
| D15 hue discrimination total error score | 2.22 (6.46) | 2.60 (4.93) | ns |
| HADS depression score | 1.86 (2.12) | 3.78 (2.81) | ns |
| HADS anxiety score | 3.97 (3.48) | 5.94 (4.12) | * |
| RBDSQ score | 1.84 (1.42) | 4.14 (2.45) | *** |
| Smell test (Sniffin’ Sticks) | 12.43 (2.44) | 7.65 (3.21) | *** |
| Disease duration (years) | N/A | 4.2 (2.5) | na |
| Levodopa equivalent dose (mg) | N/A | 457 (258) | na |
| Motor deficit dominance (left, right, both) | N/A | 41: 54: 5 | na |
Means (SDs) reported.
Sleep Behaviour Disorder Screening Questionnaire. Pelli-Robson: higher score is better contrast sensitivity. Binocular LogMAR: lower score is better visual acuity. D15: lower score is better colour discrimination.
***p<0.001; *p<0.05.
HADS, Hospital Anxiety and Depression Scale; MoCA, Montreal Cognitive Assessment; ns, not significant; RBDSQ, REM (rapid eye movement) Sleep Behaviour Disorder Screening Questionnaire; UPDRS-III, Unified Parkinson's Disease Rating Scale part 3.