Extra information about treatment is too much for the patient with psychosis
Abstract
Background Case law across jurisdictions requires ever more complete disclosure of material facts when obtaining consent to treatment.Aims To determine whether giving extra information impairs the mental capacity to make decisions about treatment.Method The MacCAT-T, MacCAT-FP, PANSS and GAF were administered to 88 detained forensic patients with psychosis. Two positive and two negative facts were given about each of two anti-psychotic drugs, and no treatment (twelve items). A choice was elicited. The criterion for incompetence was inability to express a choice. Two extra positive and two extra negative facts about each of the three options were given (twelve extra items) and a choice was again elicited, while repeating the MacCAT-T.Results Giving extra information led to a decline in the total score on the MacCAT-T. Twenty one were initially unable to make a choice (24%). After additional information, 33 were incapable (37.5%, Chi-squared p<0.001). Those initially incapable had the lowest scores on all measures of functional capacity and GAF, with highest scores for symptoms. Those able to choose a treatment option had the highest levels of function and least symptoms. Those who became incapable had intermediate scores.Conclusions Giving extra information made an extra 15% unable to choose. Clinical judgement must be exercised concerning the amount of information disclosed. Deciding what is material to the individual is arbitrary when so few items of information can be processed. Greater use of guardianship and independent second opinions is recommended.
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The proportion unable to express a choice increased to 37.5% if more information was given.
“increasing to 37.5% (95% CI [27 -48%]) if more information was given (Kennedy et al., 2009).”
From Decision making capacity for treatment in psychiatric inpatients: a systematic review and meta-analysis (2024) · cites this paper as Kennedy et al., 2009
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 Kennedy et al., 2009
Positive symptoms were found to be associated with incapacity in 8 studies, especially conceptual disorganization, manic symptoms, delusions and unusual thought content.
“Positive symptoms were found to be associated with incapacity in 8 studies (Dornan et al., 2015;Fraguas et al., 2007;Kennedy et al., 2009;Mandarelli et al., 2018b;G. Owen et al., 2009;Skipworth et al., 2013;Spencer et al., 2018), especially conceptual disorganization (G.Owen et al., 2009;Skipworth et al., 2013), manic symptoms (Mandarelli et al., 2014(Mandarelli et al., , 2018b;;Spencer et al., 2”
From Decision making capacity for treatment in psychiatric inpatients: a systematic review and meta-analysis (2024) · cites this paper as Kennedy et al., 2009
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 Kennedy et al., 2009
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 Kennedy et al., 2009
Six studies analyzed the relationship between psychopathological and cognitive variables with the different subscales of the MacCAT.
“Six studies analyzed the relationship between psychopathological and cognitive variables with the different subscales of the MacCAT (Bilanakis et al., 2013;Kennedy et al., 2009;Mandarelli et al., 2014Mandarelli et al., , 2018b;;Rutledge et al., 2008;Seo et al., 2011).”
From Decision making capacity for treatment in psychiatric inpatients: a systematic review and meta-analysis (2024) · cites this paper as Kennedy et al., 2009
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Self-citation
- Authors
- Kennedy, M., Dornan, J., Rutledge, E., O'Neill, H., & Kennedy, H. G.
- Affiliations
- Central Mental Hospital (IE)
- Trinity College Dublin (IE)
- Corresponding author
- Kennedy, Harry G.
- ORCID
- Kennedy, Harry G.
- Venue
- International Journal of Law and Psychiatry
- Publisher
- Elsevier BV
- Published
- 2009-11
- Volume
- 32
- Issue
- 6
- Pages
- 369-376
- ISSN
- 0160-2527 (ISSN-L)
- OpenAlex
- W2038488309
- Cited by
- 29
- References
- 30
- Citations by year
- 2026: 1 · 2025: 2 · 2024: 3 · 2023: 1 · 2022: 8 · 2021: 1 · 2020: 4 · 2019: 2 · 2018: 2 · 2017: 1 · 2015: 2 · 2014: 1 · 2012: 1
- FWCI
- 0.35
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- International Journal of Law and Psychiatry (publishedVersion)
- PubMed (publishedVersion)
- Lenus, The Irish Health Repository (Dr Steevens Hospital Library) (submittedVersion)
- Topics
- Social Sciences › Psychology › Clinical Psychology › Healthcare Decision-Making and Restraints
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Ethics and bioethics in healthcare
- Health Sciences › Medicine › Pediatrics, Perinatology and Child Health › Ethics and Legal Issues in Pediatric Healthcare
- Keywords
- informed consent, treatment refusal, decision-making capacity, psychosis, forensic psychiatric patients, antipsychotic drugs, guardianship, second opinion, functional capacity
- MeSH terms
- Adult, Choice Behavior, Commitment of Persons with Psychiatric Disorders, Decision Making, Female, Humans, Informed Consent, Ireland, Male, Patient Education as Topic, Patient Participation, Psychiatric Status Rating Scales, Psychotic Disorders, Schizophrenia, Schizophrenic Psychology, Mental Competency, Treatment Outcome, Disclosure, Comprehension
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