The main goal of this study was to show that tardive dyskinesia is more likely to develop in patients with pseudoparkinsonian symptoms than in patients not exhibiting such manifestations. This hypothesis was supported by data from three independent studies: (1) observation of neurological changes in 55 schizophrenic patients taken off a regimen of neuroleptic drugs; (2) a study of the evolution of symptoms in 400 subjects on various drug regimens over a one-year period; and (3) a controlled investigation of the effects of gradual removal of neuroleptics in four samples of patients exhibiting a variety of druginduced side effects or no drug related neurological manifestations.
Crane GE. Pseudoparkinsonism and Tardive Dyskinesia. Arch Neurol. 1972;27(5):426-430. doi:10.1001/archneur.1972.00490170058008