Validation of the MDS clinical diagnostic criteria for Parkinson's disease

BACKGROUND In 2015, the International Parkinson and Movement Disorder Society published clinical diagnostic criteria for Parkinson's disease. These criteria aimed to codify/reproduce the expert clinical diagnostic process and to help standardize diagnosis in research and clinical settings. Their accuracy compared with expert clinical diagnosis has not been tested. The objectives of this study were to validate the International Parkinson and Movement Disorder Society diagnostic criteria against a gold standard of expert clinical diagnosis, and to compare concordance/accuracy of the International Parkinson and Movement Disorder Society criteria to 1988 United Kingdom Brain Bank criteria. METHODS From 8 centers, we recruited 626 parkinsonism patients (434 PD, 192 non-PD). An expert neurologist diagnosed each patient as having PD or non-PD, regardless of International Parkinson and Movement Disorder Society criteria (gold standard, clinical diagnosis). Then a second neurologist evaluated the presence/absence of each individual item from the International Parkinson and Movement Disorder Society criteria. The overall accuracy/concordance rate, sensitivity, and specificity of the International Parkinson and Movement Disorder Society criteria compared with the expert gold standard were calculated. RESULTS Of 434 patients diagnosed with PD, 94.5% met the International Parkinson and Movement Disorder Society criteria for probable PD (5.5% false-negative rate). Of 192 non-PD patients, 88.5% were identified as non-PD by the criteria (11.5% false-positive rate). The overall accuracy for probable PD was 92.6%. In addition, 59.3% of PD patients and only 1.6% of non-PD patients met the International Parkinson and Movement Disorder Society criteria for clinically established PD. In comparison, United Kingdom Brain Bank criteria had lower sensitivity (89.2%, P = 0.008), specificity (79.2%, P = 0.018), and overall accuracy (86.4%, P