Abstract
Clinicians require quantitative measures of functional movement to inform care decisions for persons with Parkinson's disease (PWPs). To address this need, we developed the Parkinson's Disease-Functional Movement Battery (PD-FUNC), which includes valid items from existing assessments and evaluates five key areas from the MDS-UPDRS-III: manual dexterity, functional strength, locomotion, static balance, and activities of daily living. This study assessed the PD-FUNC's ability to distinguish between PWPs and healthy controls based on effect sizes and analyzed differences according to disease progression using years since diagnosis and MDS-UPDRS-III scores, as well as Hoehn & Yahr (H&Y) stages. The test was administered to 81 PD patients (H&Y stages 1-3) and 81 age-matched controls. All items, except grip force, discriminated effectively, with dexterity tasks showing the highest sensitivity (effect size r = 0.52-0.63). The PD-FUNC distinguished PD stages well, revealing early symptoms through dexterity tests (p = 0.001) and late-stage symptoms via dynamic stability tests. The PD-FUNC could provide a comprehensive assessment within 30-40 min and could be used to evaluate disease progression and medication effectiveness at home and in clinical settings.