Confirmatory factor analysis within the Tracking Parkinson’s cohort showing standardised factor loadings of variables selected from exploratory factor analysis and measures of model fit
| Variable | Factor 1 Psychological well-being | Factor 2 Non-tremor motor |
| MDS-UPDRS I apathy | 0.512 | |
| MDS-UPDRS I fatigue | 0.599 | |
| MDS-UPDRS I pain | 0.544 | |
| BFI—neuroticism | 0.459 | |
| HADS anxiety | 0.795 | |
| HADS depression | 0.863 | |
| QUIP | 0.307 | |
| MDS-UPDRS III speech | 0.420 | |
| MDS-UPDRS III rigidity subscore | 0.535 | |
| MDS-UPDRS III bradykinesia subscore | 0.769 | |
| MDS-UPDRS III postural subscore | 0.609 | |
| CFI=0.909 | ||
| TLI=0.932 | ||
| RMSEA=0.063 |
CFI, TLI and RMSEA are all measures of model fit.
BFI, Big five inventory; QUIP, Questionnaire for Impulsive-Compulsive Disorders in Parkinson's disease.
CFI, Comparative Fit Index; HADS, Hospital Anxiety and Depression Scale; MDS, Movement Disorders Society; RMSEA, root mean square error of approximation; TLI, Tucker-Lewis Index; UPDRS, Unified Parkinson’s Disease Rating Scale.