The participant has a diagnosis of Parkinson's disease according to the diagnostic criteria of the UK Parkinson's Disease Society Brain Bank. 
The participant has received a levodopa combination drug for >= 1 month and has either of the following. 
Wearing off phenomenon 
Decreased response to levodopa combination drugs 
The participant has received a levodopa combination drug without change in the dose regimen. 
The participant is an outpatient of either sex aged >= 30 and < 80 years. 

NCT02337764_inc_T1
Condition
Parkinson's disease
NCT02337764_inc_T2
Measurement
UK Parkinson's Disease Society Brain Bank
NCT02337764_inc_T3
Drug
levodopa combination
NCT02337764_inc_T4
Temporal
>= 1 month
NCT02337764_inc_T6
Condition
Wearing off phenomenon
NCT02337764_inc_T7
Condition
Decreased response
NCT02337764_inc_T8
Drug
evodopa combination drugs
NCT02337764_inc_T9
Drug
levodopa combination drug
NCT02337764_inc_T10
Qualifier
without change in the dose regimen
NCT02337764_inc_T11
Person
aged
NCT02337764_inc_T12
Value
>= 30 and < 80 years