Journal Article

Magnitude of Impairment in Decisional Capacity in People With Schizophrenia Compared to Normal Subjects: An Overview

Dilip V Jeste, Colin A Depp and Barton W Palmer

in Schizophrenia Bulletin

Published on behalf of Maryland Psychiatric Research Center

Volume 32, issue 1, pages 121-128
ISSN: 0586-7614
Published online September 2005 | e-ISSN: 1745-1701 | DOI:
Magnitude of Impairment in Decisional Capacity in People With Schizophrenia Compared to Normal Subjects: An Overview

More Like This

Show all results sharing this subject:

  • Child and Adolescent Psychiatry


Show Summary Details


The capacity of individuals with schizophrenia to make decisions related to research participation or clinical treatment has received increasing empirical attention. A number of studies have compared patients with schizophrenia to nonpsychiatric comparison subjects (NPCs) on structured measures of decision-making capacity. In this review, we evaluated the magnitude of the difference between schizophrenia and NPC groups reported across these studies, as well as the influence of sample characteristics on observed effect sizes. We also computed the effect sizes of group differences in psychopathology and cognitive deficits. Twelve studies met the search criteria; a majority of them reported data using the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) or for Treatment (MacCAT-T). The mean effect size (evaluated in terms of Cohen's d) for group differences on the Understanding subscale of the MacCAT instruments was 0.88 (SD = 0.40); it was twice as high among inpatient samples as among outpatients. Similar differences were observed in terms of Appreciation and Reasoning subscales, but the effect sizes for Expression of Choice were small (mean d = 0.29, SD = 0.24). Notably, these observed effect sizes were generally smaller than those for differences between schizophrenia and NPC groups in psychopathology (mean d = 2.06, SD = 1.03) and cognition (mean d = 1.01, SD = 0.61). The published studies demonstrate a substantial heterogeneity in decision-making capacity among people with schizophrenia, as well as among NPCs, suggesting that the presence of schizophrenia does not necessarily mean the patient has impairment in capacity.

Keywords: schizophrenia; decisional capacity; competence; consent; cognition; psychosis

Journal Article.  3956 words.  Illustrated.

Subjects: Child and Adolescent Psychiatry

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.