Table 1.

Results of relevant neuropsychological studies in aggressive schizophrenic patients.

Authors	Sample characteristics	Results of relevant neuropsychological studies
Lafayette et al. [58]	96 schizophrenic patients (34 violent arrests, 23 nonviolent arrest, 39 no arrest)	No significant differences between the groups in the WAIS, Wisconsin Card Sortig Test, Trail Making Test, Verbal fluency Test, Stroop Test, American National Adult Reading Test
Krakowski et al. [59]	32 transiently violent schizophrenic patients, 27 persistently violent schizophrenic patients	No difference in the average performance and verbal IQ on the WAIS-R
Wong et al. [60]	20 male schizophrenic patients who had committed several violent offenses, 19 male schizophrenic patients who had committed only 1 violent offense.	No difference in the WAIS performance between the groups
Silver et al. [61]	35 violent patients with chronic schizophrenia or schizoaffective disorder, 35 nonviolent schizophrenic patients, 46 healthy controls	No difference between violent and nonviolent schizophrenic patients in the cognitive test battery
Fullam and Dolan [62]	33 violent and 49 nonviolent male forensic inpatients with schizophrenia	No difference between violent and nonviolent schizophrenic patients in the cognitive test battery but lower IQ scores in the violent schizophrenic patients
Roy et al. [63]	20 chronic, treatment-resistant inpatients with schizophrenia; (11 violent and 9 low-violent men)	Violent patients outperformed nonviolent patients on the verbal IQ, digit symbol test, block design
Lapierre et al. [64]	31 schizophrenic men (outpatients) and 30 healthy control subjects	Higher level of violence in the more cognitively functional individuals on the Wisconsin Card Sorting Test and Controlled Oral Word Association test
Rasmussen [65]	13 inpatients aggressive schizophrenic patients from a maximum security psychiatric unit, 13 nonaggressive schizophrenic patients, 13 healthy controls	Violent schizophrenic patients outperformed nonviolent schizophrenic patients on the Trail Making Test and showed faster reaction time on all reaction time tests but more failed inhibitions on the Go-NoGo test
Krakowski et al. [66]	28 high, 27 low, and 34 nonviolent schizophrenic patients	High-violent patients were more impaired on the Benton Visual Retention Test, digit symbol test, block design and had lower performance IQ scores on the WAIS-R
Adams et al. [67]	37 male schizophrenic patients	History of violent arrests but not inpatients violence was associated with impairment on the Luria Nebraska neuropsychological battery
Barkataki et al. [68]	13 individuals with a history of serious violence and a diagnosis of antisocial personality disorder, 13 individuals with a history of violence and schizophrenia, 15 individuals with schizophrenia without a history of violent behaviour, 15 healthy control subjects	Violent schizophrenic patients had a higher number of errors in the Wisconsin Card Sorting Test
Foster et al. [69]	1 year prospective study of aggression in 23 male forensic psychiatric inpatients	Scores on Stroop Color Word Tasks, Judgment of Line Orientation Test, Symbol Digit Modalities Test only significantly predicted frequency but not severity
Krakowski et al. [70]	33 psychiatric violent inpatients versus 69 nonviolent psychiatric inpatients	History of community violence was related to impairment on some Wisconsin Card Sorting Subtests, finger tapping, Perdue pegboard

WAIS-R: Wechsler Adult Intelligence Scale-revised.