The<unk>  is a commonly used system for describing how the symptoms of Parkinson's disease progress. The<unk>  allocates stages from 0 to 5 to indicate the relative level of disability.
Stage one: Symptoms on one side of the body only.
Stage two: Symptoms on both sides of the body.  No impairment of balance.
Stage three: Balance impairment.  Mild to moderate disease.  Physically independent.
Stage four: Severe disability, but still able to walk or stand unassisted.
Stage five: Wheelchair-bound or bedridden unless assisted.
Hoehn and Yahr scale
Mallampati score
Tygerberg score
Alvarado score
AMUSE score
Child-Turcotte classification
Malinas score
Rogers score