Table 1

Clinical diagnostic criteria

Criteria for diagnosis of Parkinson’s disease	Criteria for diagnosis of multiple system atrophy
Patients must have a history, or show three or more, of the following clinical features, including at least two of those marked by an asterisk	Patients must have a history, or show two or more, of the following clinical features
Rest tremor*^25–²⁷	Dysarthria³⁵
Asymmetrical onset*^26, ^28–³⁰	Dysphagia³¹
Preserved postural stability*^31, ³²	Facial/cervical dystonia^25, ^35–³⁷
Typical levodopa responsiveness*^26, ^29,^31, ³³	Action myoclonus³⁵
Typical dyskinesias*^25, ²⁸	Stridor/vocal cord palsy^25,^35, ³⁸
Dementia*^25,^28, ³¹	Hand contractures²⁵
Cognitive fluctuations³⁴	Corticospinal tract signs^25, ³⁵
Psychosis^22,^30, ³¹	Gait ataxia³⁵
	Limb ataxia³⁵
	Nystagmus³⁵

Exclusion criterion: ataxia of limb or gait	Exclusion criterion: dementia³¹