Table 1.

Clinical scales and tests.

Outcome	Outcome Measure	Description
Motor Impairment	Modified Hoehn and Yahr (mH&Y)	mH&Y evaluates the staging of the functional disability due to PD, from 1 (unilateral involvement only) to 5 (wheelchair-bound or bedridden) [28,31].
	Movement Disorders Society—Unified Parkinson’s Disease Rating Scale Part 2 (MDS-UPDRS II)	Self-administered questionnaire focused on difficulties in 13 motor aspects of daily living. Each item is rated from 0 (normal) to 4 (severe) [32].
	Movement Disorders Society—Unified Parkinson’s Disease Rating Scale Part 3 (MDS-UPDRS III)	Assessment of motor signs of PD through the evaluation of 18 aspects rated by the examiner between 0 (normal) and 4 (severe) [32].
Gait and Balance	6-Minute Walk Test (6MWT)	Assessment of walking endurance by measuring the distance walked on a flat hard surface in 6 min [5].
	Timed Up and Go (TUG)	Assessment of mobility and dynamic balance [33]. It requires subjects to rise from a chair, walk 3 m, turn, walk back to the chair and sit down. The score is represented by the time taken to perform the test.
	Postural Instability and Gait Difficulty (PIGD)	Index defined by the mean scores of the MDS-UPDRS items 2.12, 2.13, 3.10, 3.11, 3.12 [34].
Asymmetry	Worst Leg and Best Leg Impairments	Indices derived by summing the MDS-UPDRS III scores related to right and left lower limb (items 3.3, 3.7, 3.8, 3.17). The highest (lowest) index quantifies the worst leg (best leg) impairment.
	Leg Asymmetry Index	Ratio between the difference of the worst and best leg, and the sum of the worst and best leg [35].
Akinesia/ Bradykinesia	Akinesia/Bradykinesia Index	Index evaluating the loss/slowness of spontaneous voluntary limb movement. It is derived by adding the MDS-UPDRS III scores of items from 3.4 to 3.11, 3.13 and 3.14 [36].
Rigidity	Rigidity index	Index defined by summing MDS-UPDRS III scores of item 3.3.
Tremor	Tremor index	Index defined by the mean scores of the MDS-UPDRS items 2.10, 3.15, 3.16, 3.17 and 3.18 [34].
Cognitive Impairment	Montreal Cognitive Assessment (MoCA)	MoCA consists of 16 items assessing different cognitive domains, including visuospatial and executive functions, memory, attention and orientation). The maximum score is 30 points indicating normal cognition. In the present paper, MoCA scores adjusted following Santangelo et al. [28] were also reported.

PD: Parkinson’s Disease.