The Nithsdale schizophrenia survey: III. Handedness and tardive dyskinesia.

Handedness was assessed in 87 per cent (n = 116) of all known schizophrenics from a discrete geographical area, Nithsdale in Dumfries and Galloway Region. Seventy-three per cent were right-handed, a proportion greater than that found in a normal population. It was especially Feighner positive schizophrenics and non-in-patients who produced the excess of right-handers. Within the Feighner positive group, 68 per cent of mixed or left-handers, but only 29 per cent of right-handers, had tardive dyskinesia.