Relationship of individual cognitive abilities to specific components of decisional capacity among middle-aged and older patients with schizophrenia

Prior empirical studies suggest that cognitive impairment is the strongest predictor of capacity to consent to research among persons with schizophrenia. Yet, despite the frequency and importance of cognitive deficits and impaired decisional capacity in schizophrenia, the scope of neuropsychological testing in most published reports in this area has been relatively narrow. In the present study of 70 people with schizophrenia aged 40 to 70 years we evaluated decisional capacity with the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR). Participants were also evaluated with standardized rating scales of psychopathology and level of insight and with a comprehensive neuropsychological test battery that permitted evaluation of 7 specific cognitive abilities. Results showed that the strongest correlates of capacity (particularly, understanding and appreciation of disclosed information) were cognitive test scores, but there was little evidence of differential relationships between individual cognitive abilities and specific dimensions of capacity. Understanding was also correlated with severity of negative symptoms and of general psychopathology, but not with age, education, severity of positive or depressive symptoms, or level of insight. Understanding improved over successive presentations of consent-relevant information. The results suggest that age and diagnosis should not be viewed as determinants of decisional capacity; investigators should be alert to the presence of cognitive deficits, as well as negative symptoms. Also, an interactive dialogue between patient and investigator with repeated presentation of information is likely to aid understanding of disclosed information among patients with schizophrenia.     

Correlates of treatment-related decision-making capacity among middle-aged and older patients with schizophrenia

BACKGROUND: Antipsychotic medications constitute the backbone of treatment for schizophrenia. Current guidelines require clinicians to obtain patients' informed consent for treatment, but few empirical studies of the capacity of patients with schizophrenia for meaningful consent in this context exist. This issue may be particularly relevant for middle-aged and older patients, as the cognitive changes associated with normal aging may have an adverse impact on decision-making processes. We examined the range, stability, and correlates of treatment-related decisional capacity in this patient population. METHODS: Participants included 59 middle-aged and older patients with schizophrenia or schizoaffective disorder and 38 normal comparison subjects. Baseline measures included the MacArthur Competence Assessment Tool for Treatment (MacCAT-T), psychopathology rating scales, and the Mattis Dementia Rating Scale. Patients also completed a neuropsychological test battery. The MacCAT-T was readministered to patients at a 1-month follow-up. RESULTS: Relative to the comparison subjects, the patients had worse understanding of disclosed material; however, a wide range of performance was observed among patients. Variability in MacCAT-T performance was not predicted by demographic characteristics; there were no significant correlations between psychopathology ratings and MacCAT-T scores. Cognitive test scores were often significant correlates of capacity, particularly in terms of understanding and reasoning. The MacCAT-T scores were stable during the 1-month follow-up. CONCLUSIONS: Overall, middle-aged and older outpatients with schizophrenia had worse understanding of disclosed information than did normal comparison subjects, but such group comparisons obscure remarkable heterogeneity among patients. Differences in capacity appeared more related to cognitive functions than to severity of psychopathology. Such information about barriers to capacity may help in developing more effective methods of providing informed consent.     

Using a brief intervention to improve decisional capacity in schizophrenia research

Studies have shown that individuals with psychiatric or general medical illness can benefit from interventions designed to enhance decisional capacity for research informed consent. In some cases, interventions have been rather lengthy or complex. The current study was designed to determine whether a brief intervention could improve decisional capacity in people with schizophrenia. Thirty individuals with schizophrenia and 30 healthy comparison participants were presented with a hypothetical research scenario. Decisional capacity was assessed with the MacArthur Competence Assessment Tool-Clinical Research version. Those with schizophrenia received a brief intervention aimed at improving understanding of the research protocol, after which decisional capacity was reassessed. A neuropsychological battery and symptom rating scales were also administered. At baseline, the schizophrenia group earned significantly lower scores than the comparison group on 2 aspects of decisional capacity (understanding, appreciation). At follow-up, the schizophrenia group had improved significantly on understanding and was no longer significantly different from the comparison group on any of the 4 dimensions of decisional capacity. Follow-up analyses also showed a significant effect of the intervention on a subset of the schizophrenia group who had performed most poorly at baseline. Participants with schizophrenia earned significantly lower scores than those in the comparison group across multiple neuropsychological domains. These findings add to the existing literature indicating that brief interventions can improve decisional capacity in individuals with schizophrenia, despite the fact that the illness typically causes significant cognitive dysfunction. The use of such interventions will enable a larger number of people with schizophrenia to make informed decisions regarding research participation.     

A preliminary study of interactive questioning methods to assess and improve understanding of informed consent among patients with schizophrenia

Growing recognition of the inadequacy of traditional methods of providing informed consent, especially for individuals vulnerable to impaired decisional capacity, has spurred recent interest in how to assess and improve components of consent-related decision making. In this preliminary study, we aimed to compare different methods of interactive questioning during presentation of research consent information among patients with schizophrenia. Patients were randomized to receive either standard administration (SA) of a consent form or one of two interactive questioning methods: Corrective Feedback (CF), in which the correct answer was provided following the participant's response, or Errorless Learning (EL), in which correct answers were provided just prior to the question. The MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) was used to measure understanding, appreciation, reasoning, and expression of a choice following presentation of the consent form. There was no significant effect of condition (SA vs. EL vs. CF) on any of the components of decisional capacity. Understanding scores measured during the consent process were higher than those measured afterward, but the two scores were highly correlated. Thus, the results of this randomized study suggest that interactive questioning neither helped nor harmed understanding, appreciation, or reasoning among patients with schizophrenia. Other considerations, however, may favor use of such methods in the consenting process.     

A direct comparison of research decision-making capacity: schizophrenia/schizoaffective, medically ill, and non-ill subjects

To characterize predictors of impairment in research decision-making capacity, we undertook a direct comparison of schizophrenia/schizoaffective (n=52), medically ill (diabetic; n=51), and non-ill (n=57) subjects. Scores on the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) were correlated with demographic variables and scores on the Positive and Negative Syndrome Scale (PANSS), Mini-Mental State Examination (MMSE), and Short-Form-36 (SF-36). Across diagnoses, cognitive capacity, physical functioning, and a diagnosis of mental illness had the greatest impact on decision-making capacity, with level of education also having an impact. 69-89% of schizophrenia/schizoaffective subjects attained MacCAT-CR subscale scores achieved by almost all comparison (98-100%) and medically ill (94-100%) subjects. Positive, negative, and general psychotic symptoms correlated with poorer scores. Prior research experience, number of queries used during interview, and emotional functioning also predicted MacCAT-CR scores. These data suggest that investigators and IRBs should consider a number of variables, many of which reach across diagnoses, as they decide which populations and individual subjects may require more intensive screening for decisional impairment or educational interventions to improve their abilities to make capable decisions about research participation.     

Decisional capacity of depressed elderly to consent to electroconvulsive therapy

The purpose of this article is to determine the abilities of severely depressed elderly to consent to electroconvulsive therapy (ECT) and to investigate the impact of educational intervention on their capacity. Forty severely depressed adults referred for ECT, with Mini-Mental State Examination scores greater than 20, were recruited. Using the MacArthur Competence Assessment Tool for Treatment (MacCAT-T), decisional capacities were assessed at baseline and reassessed after education. Between the 2 assessments, all subjects received standard education, and half of the group was subsequently randomized to receive further education. At baseline, the geriatric group scored lower on understanding, reasoning, and choice and higher on appreciation. After education, all MacCAT-T scores increased for both age groups. Depressed elderly in the sample, as a group, had adequate decisional capacities to consent to ECT. They showed greater improvement in decisional capacity with education. The findings highlight the importance of providing education to the elderly to optimize their ability to give informed consent.     

Multimedia consent for research in people with schizophrenia and normal subjects: a randomized controlled trial

Limitations of printed, text-based, consent forms have long been documented and may be particularly problematic for persons at risk for impaired decision-making capacity, such as those with schizophrenia. We conducted a randomized controlled comparison of the effectiveness of a multimedia vs routine consent procedure (augmented with a 10-minute control video presentation) as a means of enhancing comprehension among 128 middle-aged and older persons with schizophrenia and 60 healthy comparison subjects. The primary outcome measure was manifest decisional capacity (understanding, appreciation, reasoning, and expression of choice) for participation in a (hypothetical) clinical drug trial, as measured with the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) and the University of California San Diego (UCSD) Brief Assessment for Capacity to Consent (UBACC). The MacCAT-CR and UBACC were administered by research assistants kept blind to consent condition. Additional assessments included standardized measures of psychopathology and cognitive functioning. Relative to patients in the routine consent condition, schizophrenia patients receiving multimedia consent had significantly better scores on the UBACC and on the MacCAT-CR understanding and expression of choice subscales and were significantly more likely to be categorized as being capable to consent than those in the routine consent condition (as categorized with several previously established criteria). Among the healthy subjects, there were few significant effects of consent condition. These findings suggest that multimedia consent procedures may be a valuable consent aid that should be considered for use when enrolling participants at risk for impaired decisional capacity, particularly for complex and/or high-risk research protocols.     

Brain response correlates of decisional capacity in schizophrenia: a preliminary FMRI study

The capacity of schizophrenia patients to make decisions regarding research consent relates to neurocognition, but the exact nature of the relationship is unclear. The authors examined the correlation of scores on the MacArthur Competence Assessment Tool for Clinical Research with functional magnetic resonance imaging brain response during a verbal learning task. Understanding of a consent form correlated with activation of the right hippocampus during verbal learning and with brain response in a large area that included the bilateral parahippocampus, cerebellum, and thalamus. Reasoning scores were not significantly related to brain activation. Understanding deficits during informed consent relates to particular brain abnormalities among schizophrenia patients.     

Prevalence and correlates of adequate performance on a measure of abilities related to decisional capacity: differences among three standards for the MacCAT-CR in patients with schizophrenia

Despite the availability of structured decision-making capacity assessment tools, insufficient guidance exists for applying their results. Investigators often use cutpoints on these instruments to identify potential subjects in need of further assessment or education. Yet, information is lacking regarding the effects of different cutpoints on the proportion and characteristics of individuals categorized as possessing adequate or impaired decisional abilities for consent to research. To demonstrate the potential impact of different standards, we informed 91 individuals, aged 50 or older with a diagnosis of schizophrenia or schizoaffective disorder, about a hypothetical clinical trial, and assessed their decisional abilities with the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR). Three published MacCAT-CR-based standards were applied to participants' scores to examine the rates and correlates of categorical determinations of adequate performance. The three standards ranged in stringency: the most stringent incorporated cutpoints on all three of the major MacCAT-CR subscales (Understanding, Appreciation, and Reasoning); the other two standards required threshold performance only on the Understanding subscale. The most stringent standard resulted in a 57% rate of impaired performance; the intermediate standard, 19%; and the least stringent standard, 8%. Nearly half of the participants (n=45) were classified as having performed adequately by the least stringent standard yet inadequately by the most stringent. The majority of these 45 were impaired on the Appreciation subscale (n=9), Reasoning (n=15), or both (n=18). Cognitive functioning was correlated with performance status for the more stringent standards. These findings underscore the need for refinement of capacity assessment procedures and for improvements in the use of capacity assessment tools for screening purposes and to assist in categorical capacity determinations.     

Competence to consent to research among long-stay inpatients with chronic schizophrenia

OBJECTIVE: Questions have been posed about the competence of persons with serious mental illness to consent to participate in clinical research. This study compared competence-related abilities of hospitalized persons with schizophrenia with those of a comparison sample of persons from the community who had never had a psychiatric hospitalization. METHODS: The study participants were administered the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR), a structured instrument designed to aid in the assessment of competence to consent to clinical research. The scores of 27 persons who met DSM-IV criteria for schizophrenia who were long-stay patients on a state hospital research ward were compared with those of 24 individuals from the community who were of similar age, gender, race, and socioeconomic status. RESULTS: Significant differences were found between the patients and the community sample on three measures of competence-related abilities: understanding, reasoning, and appreciation. Degree of psychopathology and cognitive functioning were significantly negatively correlated with understanding and appreciation among the patients with schizophrenia. Length of hospitalization was significantly negatively correlated with all measures of decision-making capacities. CONCLUSIONS: The generally poor performance of the long-stay patients with chronic schizophrenia highlights the difficulties this group is likely to encounter in providing consent to research. However, variation across the sample points to the need for individualized assessment and for validated techniques for facilitating decision making in the face of decisional impairments.     

Comparison of two enhanced consent procedures for patients with mild Alzheimer disease or mild cognitive impairment.

OBJECTIVE: The objective of this study was to evaluate the feasibility, acceptability, and preliminary efficacy of two enhanced consent procedures provided to patients with Alzheimer disease or mild cognitive impairment that used either a PowerPoint presentation or an enhanced printed consent form. METHODS: Patients randomly assigned to an enhanced written consent procedure or slideshow presentation were assessed with the MacArthur Competence Assessment Tool for Clinical Research. RESULTS: Verbal reexplanation was associated with improved understanding in both conditions. Level of understanding did not significantly differ between the two consent groups, but administration time for slideshow presentation was less than that for an enhanced written consent procedure. CONCLUSION: Enhanced consent procedures are feasible and useful for consent to research among patients with mild cognitive impairment or mild Alzheimer disease.     

Magnitude of impairment in decisional capacity in people with schizophrenia compared to normal subjects: an overview

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.     

Diminished capacity to make treatment decision for COVID-19 vaccination in schizophrenia

Recent evidence suggests that people with schizophrenia are at high risk for severe COVID-19 and should be prioritized for vaccination. However, impaired decision-making capacities could negatively affect the uptake of COVID-19 vaccination in this population. Capacity to consent to COVID-19 vaccination was assessed in 80 outpatients with schizophrenia. Using the MacArthur Competence Assessment Tool for Treatment, 56.3% of the sample were classified as having diminished capacity to consent to the vaccination. Diminished capacity to consent to COVID-19 vaccination was associated with lower vaccination rates, poorer cognition and higher level of psychotic symptoms. Developing interventions for enhancing informed consent for vaccination is urgent within this population.

     

Assessing decisional capacity for clinical research or treatment: a review of instruments

OBJECTIVE: The need to evaluate decisional capacity among patients in treatment settings as well as subjects in clinical research settings has increasingly gained attention. Decisional capacity is generally conceptualized to include not only an understanding of disclosed information but also an appreciation of its significance, the ability to use the information in reasoning, and the ability to express a clear choice. The authors critically reviewed existing measures of decisional capacity for research and treatment. METHOD: Electronic medical and legal databases were searched for articles published from 1980 to 2004 describing structured assessments of adults' capacity to consent to clinical treatment or research protocols. The authors identified 23 decisional capacity assessment instruments and evaluated each in terms of format, content, administration features, and psychometric properties. RESULTS: Six instruments focused solely on understanding of disclosed information, and 11 tested for understanding, appreciation, reasoning, and expression of a choice. The instruments varied substantially in format, degree of standardization of disclosures, flexibility of item content, and scoring procedures. Reliability and validity also varied widely. All instruments have limitations, ranging from lack of supporting psychometric data to lack of generalizability across contexts. CONCLUSIONS: Of the instruments reviewed, the MacArthur Competence Assessment Tools for Clinical Research and for Treatment have the most empirical support, although other instruments may be equally or better suited to certain situations. Contextual factors are important but understudied. Capacity assessment tools should undergo further empirically based development and refinement as well as testing with a variety of populations.     

Competence to give informed consent in acute psychosis is associated with symptoms rather than diagnosis

To investigate the association between competence to give informed consent to treatment, specific symptomology and diagnostic category, 110 inpatients diagnosed with DSM-IV acute schizophrenia (n = 64), schizoaffective disorder (n = 25) and bipolar affective disorder (n = 21) were interviewed using the MacArthur Competence Assessment Tool for Treatment (MacCAT-T) and the Positive and Negative Syndrome Scale (PANSS). Results indicated no significant difference in competence between the three disorders. Elevated positive, cognitive and excitement PANSS factor scores had lower MacCAT-T scores. Further analyses indicated symptoms that impair cognition; particularly, conceptual disorganisation and poor attention were most consistently related to poor performance on competence tests.     

Assessing decision-making capacity at end of life

Objective

Patients with terminal illness often face important medical decisions that may carry ethical and legal implications, yet they may be at increased risk for impaired decisional capacity. This study examined the prevalence of impairment on the four domains of decisional capacity relevant to existing legal standards.

Method

Twenty-four adults diagnosed with a terminal illness completed the MacArthur Competence Assessment Tool for Treatment, a semi-structured measure of decision-making capacity and measures of cognitive functioning and psychological distress.

Results

Approximately one third of the sample demonstrated serious impairment on at least one domain of decisional capacity. The greatest proportion of impairment was found on subscales that rely heavily on verbal abilities. Decisional capacity was significantly associated with cognitive functioning and education, but not with symptoms of anxiety or depression.

Conclusions

This study is the first to examine decisional capacity in patients with terminal illness relative to legal standards of competence. Although not universal, decisional impairment was common. Clinicians working with terminally ill patients should frequently assess capacity as these individuals are called on to make important medical decisions. Comprehensive assessment will aid clinicians in their responsibility to balance respect for patient autonomy with their responsibility to protect patients from harm resulting from impaired decisional capacity.     

Decisional capacity of severely depressed patients requiring electroconvulsive therapy

OBJECTIVE: The decisional capacity of severely depressed people frequently comes into question. The ability to improve this decisional capacity through educational efforts alone is not known. Our study aimed to determine the decisional capacity of severely depressed people requiring electroconvulsive therapy (ECT), and whether educational interventions improve their ability to provide informed consent for ECT. MATERIALS AND METHODS: Forty subjects with severe depression were recruited. Using the MacArthur Competence Assessment Tool for Treatment instrument, decisional capacity was assessed at baseline and reassessed after education. All of the subjects received standard education. Additionally, half were blindly randomized to receive an experimental educational intervention. RESULT: SAt baseline, there was no statistical difference in the decisional capacity between the standard and experimental intervention groups. After educational interventions, all four areas of decisional capacity improved for both groups (understanding p < 0.001, reasoning p < 0.001, appreciation p = 0.031, choice p = 0.006). However, there was no measurable additional improvement in scores for those randomized to receive additional education. CONCLUSION: Our findings indicate that this group of severely depressed people had good decisional capacities to give informed consent. Education improved their decisional capacity. There is an endpoint beyond which additional educational intervention does not result in measurable improvement in decisional capacity.     

Are non-demented patients with Parkinson's disease able to decide about their own treatment?

IntroductionPatients with Parkinson's disease (PD) are often confronted with difficult medical decisions, which might be hampered by cognitive impairment or chronic stress. Little is known, however, about the capacity to make medical decisions and the influence of cognition and stress on this ability. This study determined whether non-demented Parkinson's disease patients are able to make medical decisions and whether this capacity is influenced by cognition and stress.MethodsForty-six Parkinson's disease patients and 94 healthy controls were assessed with the MacArthur Competence Assessment Tool for Treatment during which participants were presented with deep brain stimulation as a treatment option for a fictional Parkinson's disease patient. Furthermore, all participants were examined with a stress questionnaire and a neuropsychological test battery.ResultsParkinson's disease patients performed better on the total scale and ‘Understanding’ subscale of the MacArthur Competence Assessment Tool for Treatment than healthy controls. Lower performance on the Concept Shifting Test in the Parkinson's disease group and lower performance on Letter Digit Substitution Test in the healthy control group predicted lower medical decision-making capacity. No association was found between stress and medical decision-making.ConclusionNon-demented Parkinson's disease patients show no impairments in medical decision-making compared to healthy controls. In fact, Parkinson's disease patients have a better understanding of their disease and the benefits and risks of treatment options than healthy controls. Psychomotor speed and attention were negatively associated with medical decision-making in both groups. This implies that when these cognitive functions decline, the capacity to make medical decisions also declines.     

Treatment-related decision-making capacity in middle-aged and older patients with psychosis: a preliminary study using the MacCAT-T and HCAT.

The authors conducted a preliminary examination of treatment-related decision-making capacity (DMC) in middle-aged and older psychosis patients. The MacArthur Competency Assessment Tool for Treatment (MacCAT-T) was administered to measure DMC among 16 patients with psychotic disorders and without dementia (mean age: 54.6 [SD 7.2] years). The impact of repeated learning trials on patients' understanding was assessed with the Hopkins Competency Assessment Test (HCAT). Subjects were also assessed with the Positive And Negative Syndrome Scale and Mattis' Dementia Rating Scale. There was a wide range of performance on the MacCAT-T; the levels and range of MacCAT-T scores were similar to those previously reported among younger acutely hospitalized patients in the MacCAT-T validation study. Patients' understanding of disclosed material on the HCAT improved significantly over repeated presentations. Although there were no statistically significant correlations observed between DMC and demographic characteristics, severity of symptoms, or global cognitive deficits, the sample size provided limited power to detect such associations. Results point to the importance of assessing DMC and to the potential modifiability of initial difficulties in understanding.     

Decisional capacity of patients with schizophrenia to consent to research: taking stock

With the growth in recent years of studies of decisional capacity for research among people with schizophrenia, this is an opportune time to ask three questions: What have we learned from these studies? What remains to be learned? And what normative issues still need to be resolved? Among the things learned are that patients with schizophrenia, as a group, have lower scores on measures of decisional capacity than normals, but higher performance than patients with dementia. However, performance is highly variable within the group, correlates most strongly with neuropsychological impairment, and seems susceptible in many patients to successful remediation. The issues that remain in need of exploration include the development of a brief screening instrument for decisional capacity that can be used routinely, and the identification of those patients most likely to benefit from more intensive informational procedures. Finally, among the normative issues still in need of resolution are the degree of capacity needed to consent to research participation, how to deal with fluctuating capacity during research projects, and the legitimate extent of surrogate consent for participation of incompetent patients in research.