Defining the Parkinson's disease phenotype: initial symptoms and baseline characteristics in a clinical cohort

The demographic and clinical characteristics of the sample are thought to be phenotypically representative of 'typical' PD and were comparable to other clinic- and population-based cohorts. Initial symptoms reported by patients, including type and body location correlate tightly with initial examination findings for all cardinal symptoms of parkinsonism except rigidity. This corroboration may substantiate inclusion of such data in studies of longitudinal progression in PD.