Abstract Rated the occurrence of tardive dyskinesia (TD) in 3 kinds of populations—schizophrenics (SCZs) never treated by neuroleptics, SCZs under neuroleptic treatment, and nonpsychotics never treated by neuroleptics. Data indicate that 14% of SCZs already treated by neuroleptics and no one in the other 2 groups had TD. It is concluded the neuroleptic medication, alone or associated with other factors, is responsible for the occurrence of TD. (English abstract) (4 ref) (PsycINFO Database Record (c) 2016 APA, all rights reserved)