We are grateful to Dr Quinn for giving us the opportunity to expand on the differences between our study1 and the cited clinicopathological reports. As we pointed out in our report, in contrast to the studies in which the diagnosis was verified at autopsy, in our study we relied chiefly on multifactorial clinical criteria. We appropriately acknowledged the limitations of this method in our article. Our findings are based on the observations of experts who, by virtue of their experience in diagnosing PD, were selected to participate in the Deprenyl and Tocopherol Antioxidative Therapy for Parkinson's Disease (DATATOP) study. We also wish to emphasize that the reported figure of 8.1% is not a misdiagnosis rate, but rather a diagnosis modification rate based on our clinical diagnostic criteria.
Jankovic J, Rajput AH, McDermott M, Perl D. In reply. Arch Neurol. 2001;58(2):316-317. doi: