Functional mental capacity is not independent of the severity of psychosis
Abstract
Background Function-specific mental capacities are the legal criteria for competence. These are regarded as superior to clinical assessments of mental state and general function.Aims To determine whether tests of fitness to plead and capacity to consent are independent of each other and independent of mental state and global function in psychosis.Method The MacCAT-T and MacCAT-FP, PANSS and GAF were administered to 102 compulsorily detained forensic patients with psychosis. Criteria for incompetence were inability to express a preference concerning treatment, and independent rating as unfit to plead.Results MacCAT-T, MacCAT-FP totals and sub-scales correlated with each other and with PANSS and GAF. Those independently rated unfit to plead or who were incapable of making a treatment choice scored significantly worse on all rating scales. No test had satisfactory sensitivity or specificity.Conclusions Legal definitions of mind and of functional capacity offer a basis for structured clinical judgement regarding decision-making capacity. However, function-specific measures of understanding, reasoning and appreciation generate much the same results as measures of mental state and global functioning.
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Around 25% of patients were unable to express a choice between two medications or no treatment.
“Regarding the ability to decide between two medications or no treatment, around 25% of patients were unable to express a choice (Dornan et al., 2015;Kennedy et al., 2009;Rutledge et al., 2008)”
From Decision making capacity for treatment in psychiatric inpatients: a systematic review and meta-analysis (2024) · cites this paper as Rutledge et al., 2008
Being able to express a choice was significantly associated with better global functioning, lower positive symptoms and overall psychopathology.
“Through nonparametric analysis, being able to express a choice was also significantly associated with better global functioning (Kennedy et al., 2009;Rutledge et al., 2008), as well as lower positive symptoms and overall psychopathology (Kennedy et al., 2009;Rutledge et al., 2008).”
From Decision making capacity for treatment in psychiatric inpatients: a systematic review and meta-analysis (2024) · cites this paper as Rutledge et al., 2008
Low global functioning predicted incapacity in four studies.
“Finally, low global functioning predicted incapacity in four studies (Dornan et al., 2015;Kennedy et al., 2009;Rutledge et al., 2008;Tor et al., 2020).”
From Decision making capacity for treatment in psychiatric inpatients: a systematic review and meta-analysis (2024) · cites this paper as Rutledge et al., 2008
Cites
Diagnostic and Statistical Manual of Mental Disorders
Williams, J. B. W., & First, M. B. (2013) · Oxford University Press eBooks · doi:10.1093/acrefore/9780199975839.013.104 · Cited by 109,841 · see citing works
The Positive and Negative Syndrome Scale (PANSS) for schizophrenia.
Kay, S. R., Fiszbein, A., & Opler, L. A. (1987) · Schizophrenia Bulletin · doi:10.1093/schbul/13.2.261 · Cited by 21,378 · see citing works
Diagnostic and Statistical Manual of Mental Disorders.
Widiger, T. A. (2000) · Oxford University Press eBooks · doi:10.1037/10518-009 · Cited by 19,767 · see citing works
The MacCAT-T: a clinical tool to assess patients' capacities to make treatment decisions
(1997) · Psychiatric Services · doi:10.1176/ps.48.11.1415 · Cited by 704 · see citing works
Tests of competency to consent to treatment
Roth, L. H., Meisel, A., & Lidz, C. W. (1977) · American Journal of Psychiatry · doi:10.1176/ajp.134.3.279 · Cited by 662 · see citing works
Evaluating Competencies: Forensic Assessments and Instruments
Michalek, W., & Grisso, T. (1988) · The Journal of Criminal Law and Criminology (1973-) · doi:10.2307/1143476 · Cited by 529 · see citing works
Fusion of mental health and incapacity legislation
Dawson, J., & SZMUKLER, G. I. (2006) · The British Journal of Psychiatry · doi:10.1192/bjp.188.6.504 · Cited by 252 · see citing works
Comparison of standards for assessing patients' capacities to make treatment decisions
Grisso, T., & Appelbaum, P. S. (1995) · American Journal of Psychiatry · doi:10.1176/ajp.152.7.1033 · Cited by 250 · see citing works
Evaluating competencies: Forensic assessments and instruments
Homant, R. J. (1987) · Journal of Criminal Justice · doi:10.1016/0047-2352(87)90006-7 · Cited by 210 · see citing works
Prevalence and predictors of mental incapacity in psychiatric in-patients
Cairns, R., Maddock, C., Buchanan, A. W., David, A. S., Hayward, P., Richardson, G., SZMUKLER, G. I., & Hotopf, M. H. (2005) · The British Journal of Psychiatry · doi:10.1192/bjp.187.4.379 · Cited by 165 · see citing works
Reliability of mental capacity assessments in psychiatric in-patients
Cairns, R., Maddock, C., Buchanan, A., David, A. S., Hayward, P., Richardson, G., Szmukler, G., & Hotopf, M. (2005) · British Journal of Psychiatry · doi:10.1192/bjp.187.4.372 · Cited by 135 · see citing works
The MacArthur adjudicative competence study: Development and validation of a research instrument.
Hoge, S. K., Bonnie, R. J., Poythress, N. G., Monahan, J. T., Eisenberg, M. M., & Feucht-Haviar, T. (1997) · Law and Human Behavior · doi:10.1023/a:1024826312495 · Cited by 116 · see citing works
Mental health legislation is now a harmful anachronism
SZMUKLER, G. I., & Holloway, F. A. (1998) · Psychiatric Bulletin · doi:10.1192/pb.22.11.662 · Cited by 89 · see citing works
Assessment of Mental Capacity: Guidance for Doctors and Lawyers
(2004) · Wiley eBooks · doi:10.1002/9780470757345 · Cited by 82 · see citing works
Akinkunmi, A. (2002) · PubMed · Cited by 43 · see citing works
Long-stay forensic psychiatric inpatients in the Republic of Ireland: aggregated needs assessment
O’Neill, C., Heffernan, P., Goggins, R., Corcoran, C., Linehan, S. A., Duffy, D. M., O’Neill, H., SMITH, C. E., & Kennedy, H. G. (2003) · Irish Journal of Psychological Medicine · doi:10.1017/s0790966700007916 · Cited by 40 · see citing works
Self-citationO’Neill, C., Sinclair, H., Kelly, A., & Kennedy, H. G. (2002) · Irish Journal of Psychological Medicine · doi:10.1017/s0790966700006959 · Cited by 32 · see citing works
Self-citationEvaluating Competencies: Forensic Assessments and Instruments, Second Edition
Witt, P. H. (2003) · Psychiatric Services · doi:10.1176/appi.ps.54.6.912-a · Cited by 8 · see citing works
&NA; (1993) · Plastic & Reconstructive Surgery · doi:10.1097/00006534-199308000-00092 · Cited by 1 · see citing works
Flagged first, then by citations
Cited by
Sorted by citations
Naughton, M., Nulty, A., Abidin, Z., Davoren, M., O’Dwyer, S., & Kennedy, H. G. (2012) · BMC Research Notes · doi:10.1186/1756-0500-5-302 · Cited by 62 · see citing works
Self-citationLarkin, A., & Hutton, P. (2017) · The British Journal of Psychiatry · doi:10.1192/bjp.bp.116.193458 · Cited by 57 · see citing works
Healthcare Decision Making and the Law: Autonomy, Capacity and the Limits of Liberalism
(2011) · International Journal of Health Care Quality Assurance · doi:10.1108/ijhcqa.2011.06224eaa.015 · Cited by 53 · see citing works
Mental capacity and consent to treatment in psychiatric patients: the state of the research
Candia, P. C., & Barba, A. C. (2011) · Current Opinion in Psychiatry · doi:10.1097/yco.0b013e328349bba5 · Cited by 38 · see citing works
Capacity assessment under the Mental Capacity Act 2005: Delivering on the functional approach?
Donnelly, M. (2009) · Legal Studies · doi:10.1111/j.1748-121x.2009.00133.x · Cited by 38 · see citing works
Mandarelli, G., Tarsitani, L., Parmigiani, G., Polselli, G. M., Frati, P., Biondi, M., & Ferracuti, S. (2014) · Journal of Forensic Sciences · doi:10.1111/1556-4029.12420 · Cited by 37 · see citing works
Dornan, J., Kennedy, M., Garland, J., Rutledge, E., & Kennedy, H. G. (2015) · BMC Research Notes · doi:10.1186/s13104-015-1547-4 · Cited by 29 · see citing works
Self-citationExtra information about treatment is too much for the patient with psychosis
Kennedy, M., Dornan, J., Rutledge, E., O'Neill, H., & Kennedy, H. G. (2009) · International Journal of Law and Psychiatry · doi:10.1016/j.ijlp.2009.09.006 · Cited by 29 · see citing works
Self-citationThe influence of psychiatric symptoms and cognitive abilities on competence-related abilities
Ryba, N., & Zapf, P. (2011) · International Journal of Forensic Mental Health · doi:10.1080/14999013.2010.550982 · Cited by 26 · see citing works
Pons, E. V., Salvador‐Carulla, L., Calcedo‐Barba, A., Paz, S., Messer, T., Pacciardi, B., & Zeller, S. L. (2020) · Health Science Reports · doi:10.1002/hsr2.179 · Cited by 23 · see citing works
Kennedy, H. G., Mullaney, R., McKenna, P. F., Thompson, J., Timmons, D., Gill, P., O’Sullivan, O. P., Braham, P., Duffy, D. M., Kearns, A., et al. (2020) · BMC Psychiatry · doi:10.1186/s12888-020-02912-6 · Cited by 20 · see citing works
Self-citationThe recovery of factors associated with decision-making capacity in individuals with psychosis
Fernandez, C., Kennedy, H. G., & Kennedy, M. (2017) · BJPsych Open · doi:10.1192/bjpo.bp.116.004226 · Cited by 19 · see citing works
Self-citationMarcó-García, S., Ariyo, K., Owen, G. S., & David, A. S. (2024) · Psychological Medicine · doi:10.1017/s0033291724000242 · Cited by 18 · see citing works
Behavioral and Psychological Symptoms Impact Clinical Competence in Alzheimer’s Disease
Bertrand, E., van Duinkerken, E., Landeira-Fernández, J., Dourado, M. C. N., Santos, R. L., Laks, J., & Mograbi, D. C. (2017) · Frontiers in Aging Neuroscience · doi:10.3389/fnagi.2017.00182 · Cited by 18 · see citing works
Capacity of forensic patients to consent to treatment
Skipworth, J. J., Dawson, J., & Ellis, P. M. (2013) · Australian & New Zealand Journal of Psychiatry · doi:10.1177/0004867412468495 · Cited by 15 · see citing works
Acceptance and insight: incapacity to give informed consent
van Staden, W. (2009) · Current Opinion in Psychiatry · doi:10.1097/yco.0b013e32833168b9 · Cited by 15 · see citing works
Capacity, consent, and mental health legislation: Time for a new standard?
O'Brien, A. J. (2010) · Contemporary Nurse · doi:10.5172/conu.2010.34.2.237 · Cited by 14 · see citing works
Blake, G. A., Ogloff, J. R. P., & Chen, W. S. (2019) · International Journal of Law and Psychiatry · doi:10.1016/j.ijlp.2019.04.007 · Cited by 14 · see citing works
Buizza, C., Strozza, C., Sbravati, G., de Girolamo, G., Ferrari, C., Iozzino, L., Macis, A., Kennedy, H. G., & Candini, V. (2022) · Annals of General Psychiatry · doi:10.1186/s12991-022-00413-2 · Cited by 13 · see citing works
Self-citationCompetence to Consent to Sexual Activity in Bipolar Disorder and Schizophrenic Spectrum Disorders
Mandarelli, G., Zangaro, S., Raja, M., Azzoni, A., Tatarelli, R., & Ferracuti, S. (2011) · Archives of Sexual Behavior · doi:10.1007/s10508-011-9840-3 · Cited by 10 · see citing works
Parmigiani, G., Mandarelli, G., Meynen, G., Carabellese, F., & Ferracuti, S. (2019) · Translational Psychiatry · doi:10.1038/s41398-019-0628-x · Cited by 10 · see citing works
Assessment of decision-making autonomy in chronic pain patients: a pilot study
d’Ussel, M., Sacco, E., Moreau, N., Nizard, J., & Durand, G. (2024) · BMC Medical Ethics · doi:10.1186/s12910-024-01096-y · Cited by 10 · see citing works
Preliminary T urkish study of psychiatric in‐patients’ competence to make treatment decisions
Er, R. A., Şehiraltı, M., & Aker, A. T. (2012) · Asia-Pacific Psychiatry · doi:10.1111/appy.12000 · Cited by 9 · see citing works
Koukopoulos, A. E., Mandarelli, G., Maglio, G., Macellaro, M., Cifrodelli, M., Kotzalidis, G. D., Tarsitani, L., Biondi, M., & Ferracuti, S. (2020) · Journal of Affective Disorders Reports · doi:10.1016/j.jadr.2020.100037 · Cited by 6 · see citing works
Mandarelli, G., Parmigiani, G., Carabellese, F., Codella, S., Roma, P., Brancadoro, D., Ferretti, A., Alessandro, L., Pinto, G., & Ferracuti, S. (2019) · Medicine Science and the Law · doi:10.1177/0025802419865854 · Cited by 5 · see citing works
Marazia, C., Rucci, P., Fangerau, H., Voßberg, D., Rolfes, V., Iozzino, L., Iommi, M., Gosek, P., Heitzman, J., Ferrari, C., et al. (2022) · Schizophrenia Bulletin Open · doi:10.1093/schizbullopen/sgac037 · Cited by 4 · see citing works
Communication in Psychiatric Coercive Treatment and Patients’ Decisional Capacity to Consent
Mandarelli, G., & Parmigiani, G. (2021) · Springer eBooks · doi:10.1007/978-3-030-65106-0_7 · Cited by 3 · see citing works
Frost, K. H., Lincoln, S. H., Norkett, E. M., Jin, M. X., Gonzalez–Heydrich, J., & D’Angelo, E. J. (2015) · Ethics & Behavior · doi:10.1080/10508422.2015.1063425 · Cited by 3 · see citing works
Mandarelli, G., Moscati, F. M., Venturini, P., & Ferracuti, S. (2013) · Rivista di psichiatria · doi:10.1708/1319.14624 · Cited by 3 · see citing works
Davoren, M., O’Reilly, K., Mohan, D. J., & Kennedy, H. G. (2022) · BMJ Open · doi:10.1136/bmjopen-2021-058581 · Cited by 2 · see citing works
Self-citationNeuroethics and Treatment Without Consent
Kennedy, H. G., & Davoren, M. (2025) · Cambridge University Press eBooks · doi:10.1017/9781009587747.029 · Cited by 1 · see citing works
Self-citationKing, C., Pozzo, J. D., Ceballo, D., & Zapf, P. A. (2021) · International Journal of Forensic Mental Health · doi:10.1080/14999013.2021.1876796 · Cited by 1 · see citing works
Capacity assessment in practice
Donnelly, M. (2010) · Cambridge University Press eBooks · doi:10.1017/cbo9780511760679.005
Factors Associated with Decision Making Capacity in Older Adults
Corrigan, M. (2019) · Arrow@dit (Dublin Institute of Technology)
Expertise, Structured Professional Judgement and Risk Assessment
Davoren, M., & Kennedy, H. G. (2024) · Cambridge University Press eBooks · doi:10.1017/9781911623809.007
Self-citationMarcó-García, S., Guilera, G., Ferrer-Quintero, M., Ochoa, S., Escuder-Romeva, G., Rubio‐Abadal, E., Martínez-Mondejar, A., Cacho, N. D., Montalbán-Roca, V., Escanilla-Casal, A., et al. (2025) · Social Psychiatry and Psychiatric Epidemiology · doi:10.1007/s00127-025-02907-2
Buizza, C., Strozza, C., Sbravati, G., de Girolamo, G., Ferrari, C., Iozzino, L., Macis, A., Kennedy, H. G., & Candini, V. (2022) · Figshare · doi:10.6084/m9.figshare.21077622
Self-citationBuizza, C., Strozza, C., Sbravati, G., de Girolamo, G., Ferrari, C., Iozzino, L., Macis, A., Kennedy, H. G., & Candini, V. (2022) · Figshare · doi:10.6084/m9.figshare.21077616
Self-citationBuizza, C., Strozza, C., Sbravati, G., de Girolamo, G., Ferrari, C., Iozzino, L., Macis, A., Kennedy, H. G., & Candini, V. (2022) · Figshare · doi:10.6084/m9.figshare.21077613
Self-citationBuizza, C., Strozza, C., Sbravati, G., de Girolamo, G., Ferrari, C., Iozzino, L., Macis, A., Kennedy, H. G., & Candini, V. (2022) · Figshare · doi:10.6084/m9.figshare.21077610
Self-citationKennedy, H. G., Mullaney, R., McKenna, P. F., Thompson, J., Timmons, D., Gill, P., O’Sullivan, O. P., Braham, P., Duffy, D. M., Kearns, A., et al. (2020) · Figshare · doi:10.6084/m9.figshare.13142152
Self-citationBuizza, C., Strozza, C., Sbravati, G., de Girolamo, G., Ferrari, C., Iozzino, L., Macis, A., Kennedy, H. G., & Candini, V. (2022) · Figshare · doi:10.6084/m9.figshare.21077619
Self-citationKeppeler, H. C., Jabat, M., Machetanz, L., Bossy, M. R., Burrer, A., Vetter, S., Seifritz, E., Kirchebner, J., & Egger, S. (2026) · BMC Psychiatry · doi:10.1186/s12888-026-08401-6
- Authors
- Rutledge, E., Kennedy, M., O'Neill, H., & Kennedy, H. G.
- Affiliations
- Central Mental Hospital (IE)
- Corresponding author
- Kennedy, Harry G.
- ORCID
- Kennedy, Harry G.
- Venue
- International Journal of Law and Psychiatry
- Publisher
- Elsevier BV
- Published
- 2008-01
- Volume
- 31
- Issue
- 1
- Pages
- 9-18
- ISSN
- 0160-2527 (ISSN-L)
- OpenAlex
- W2005077180
- Cited by
- 44
- References
- 19
- Citations by year
- 2026: 1 · 2025: 2 · 2024: 3 · 2022: 8 · 2021: 2 · 2020: 4 · 2019: 4 · 2017: 3 · 2015: 2 · 2014: 1 · 2013: 1 · 2012: 3
- FWCI
- 3.72
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- International Journal of Law and Psychiatry (publishedVersion)
- PubMed (publishedVersion)
- DigitalGeorgetown (Georgetown University Library) (submittedVersion)
- Topics
- Social Sciences › Psychology › Clinical Psychology › Healthcare Decision-Making and Restraints
- Social Sciences › Psychology › Clinical Psychology › Psychopathy, Forensic Psychiatry, Sexual Offending
- Social Sciences › Sociology and Political Science › Criminal Law and Policy
- Keywords
- psychosis, fitness to plead, capacity to consent, decision-making capacity, forensic psychiatry, compulsory detention, PANSS, Global Assessment of Functioning, legal competence, sensitivity and specificity
- MeSH terms
- Adult, Choice Behavior, Cognition, Hospitals, Psychiatric, Humans, Interviews as Topic, Ireland, Psychotic Disorders, Severity of Illness Index, Mental Competency
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