March 1, 2023
The Scientific Issues Committee on behalf of the International Parkinson and Movement Disorder Society (MDS) is providing this statement regarding the diagnosis of Parkinson’s disease (PD). This statement is based on the current best available evidence.
The MDS in 2015 published the official MDS Clinical Diagnostic Criteria for Parkinson's disease (MDS-PD Criteria)1. These criteria emerged from the work of the MDS task force for the definition of PD, a group of recognized international experts in PD2.
While the MDS-PD Criteria were designed for use in research, the MDS supports their use as a general guide to diagnosis of PD in clinical settings, and the criteria currently represent the global standard for PD diagnosis. Further, these criteria have been validated against the gold standard of expert clinical diagnosis (neurologists with >10 years' experience in PD diagnosis)3.
The prerequisite to apply the MDS-PD criteria is the diagnosis of parkinsonism, which is based on three clinical motor features (bradykinesia, rest tremor, rigidity). Determination of PD as the cause of parkinsonism relies on three categories of diagnostic features: absolute exclusion criteria, red flags, and supportive criteria. The motor features and most of the diagnostic features are determined by appropriate history taking and skilled neurological examination. Therefore, diagnosis of PD requires sufficient training in neurology. Supportive criteria increase the confidence of the diagnosis, but cannot make the diagnosis on their own. The only laboratory test finding included as a supportive criterion for diagnosis of PD is cardiac sympathetic denervation on MIBG scintigraphy. Normal functional neuroimaging of the presynaptic dopaminergic system excludes a diagnosis of PD. Advances in the field will lead to continuous updates in the diagnostic criteria over time. However, there is no reliable scientific evidence to support the use of blood tests or EEG as diagnostic tests for PD and therefore they are not included in the MDS-PD criteria.