There are two ethical principles that dominate the field of capacity assessment. These principles are autonomy (self-determination) and protection (beneficence). What should a person do if his old relative who is frail and dementing begins to make decisions that put himself or herself or others in danger? At what point is a decision that is affected by a neuropsychiatric disease no longer a competent decision? This question is important in the clinical capacity assessment. The term ‘capacity’ is used to refer to a dichotomous (yes or no) judgment by a clinician as to whether a person can perform a specific task (driving independently) or make a specific decision (changing a will). There are eight major capacity domains or relevance to older adults with neuropsychiatric illness, some research think there might be even more. These eight are financial management, independent living, testamentary capacity, research consent, treatment consent, driving, voting and sexual consent. Independent living and general financial management require a broad set of cognitive and procedural skills. The other capacities are narrower in scope and they focus only on a small number of specific decisions. Decisions of capacity fall ultimately in legal judgment cases, but in practice most determinations of diminished capacity are made outside of the courtroom by attorneys, clinicians and protective service workers. An appointed surrogate (like a health care proxy) often has much to say about the capacity of the person. Many situations of diminished capacity are managed without a formal determination of incapacity or appointment of a surrogate. Somebody who is a caregiver to an adult with dementia may assume responsibility for bill paying or disallow driving. There is sometimes a fuzzy line between the family, the clinical role and judicial role in managing diminished capacities in older adults.

Changes and capacity assessment

Capacity assessment has become a topic of national concern. This is somewhat the result of sociodemographic changes. The population is ageing at a high pace and the prevalence of dementia, cognitive ageing and health issues increases largely with age. These physical and cognitive changes are linked with declines in everyday functioning. This includes loss of decision-making skills. Multiple medical conditions can effect decision-making abilities that vary across individuals. Some aspects of decision making are affected while others are not. We also have more attention to capacity issues as a result of large-scale cultural and financial changes. Because of this, courts see a rise in contested wills and guardianships and there is a higher prevalence of elder exploitation by friends and family. Because of these changes, capacity assessment has become an everyday issue that is stuck in different sectors of society. Many disciplines are involved with decision-making capacity and some of these include mental health workers, judges, police, biomedical clinicians, attorneys and relatives. Capacity determination is therefore a complex, cross-disciplinary things which involves knowledge of ethics, medical syndromes, the law and clinical assessment. Capacity assessment is researched by the legal, clinical and behavioural fields.

In the first part of the 20th century, incapacity was determined on the basis of the presence of a diagnosis alone. Sometimes also with the indication of mental status. Then there was a shift from diagnosis to the consideration of functional abilities relevant for specific capacity domains. With the emphasize on function, researchers tried to develop standardized instruments to measure skills in certain domains. For example, there are instruments to assess capacity to consent to treatment and research and instruments to assess financial decision making and to live independently. These assessment instruments try to improve upon the low reliability of more general clinical examinations. These instruments are meant to supplement the clinical judgment about the capacity. This means that a test score alone can’t substitute for a professional clinical judgment. It is difficult to develop an instrument, because there is no generally accepted criterion validity standard for capacity. Because of the development of standardized instruments, there came empirical capacity research. Research has focused on five core issues. Research has focused on the nature of capacity impairment within different groups, the reliability of capacity ratings across clinicians, the nature of capacity impairment within different patient groups, associations between different methods of capacity assessment and the longitudinal course of capacity change and decline.

Consent to medical treatment

Treatment consent capacity is important for personal autonomy. It refers to a patient’s emotional and cognitive capacity to select among treatment alternatives or to refuse a treatment. Consent capacity is important in the medical field and it requires that a valid consent to treatment be informed, voluntary and competent. Consent capacity is the ability to understand risks, benefits and alternatives to proposed health care and to make and talk about healthcare decisions. Treatment capacity is somewhat different than the other seven capacities mentioned at the beginning of this article, because it arises in a medical and not a legal setting and it involves a physician or psychologists and not a legal professional as decision maker about capacity. Also, these judgments are not subject to judicial review.

A US conceptual model of consent capacity outlines four core abilities:

1. Expressing a choice

2. Understanding: the ability to comprehend diagnostic and treatment information. Especially important in this is understanding the risks and the benefits of proposed treatments.

3. Appreciation: the ability to relate treatment and diagnostic information to one’s own situation.

4. Reasoning: the ability to rationally evaluate and compare different treatments.

The writers of this article reviewed 16 studies and they have found that older adults in long-term-care settings have high rates of capacity impairment. Also, older adults with dementia have also a reduced consent capacity. People with dementia are most impaired on measures of understanding, followed by reasoning and appreciation. There is also much agreement between physicians about the capacity. This is especially the case for dementia patients. There is not so much agreement between multiple capacity assessment methods. In some studies, the agreement between instrument-based assessment of capacity and physician-based assessment is poor, while in others it is good. The agreement is good for understanding, but poor for appreciation. In the articles, understanding was associated with conceptualization in Alzheimer’s Disease and executive functions, comprehensions and memory in people with Parkinson’s dementia. Appreciation is related to verbal fluency, visual attention and conceptualization in Alzheimer’s Disease, but no neuropsychological test was related to appreciation in Parkinson’s disease. Reasoning was related to executive functions, attention, memory and flexibility of memory in patients with Parkinson’s disease and with verbal fluency in Alzheimer’s disease. Auditory comprehension and expressing a choice are related in patients with Alzheimer’s disease and expressing a choice is related to memory, attention and executive functions in Parkinson’s disease. A factor study showed that neuropsychological factors predicted understanding, but they had modest to low prediction for the other three things.

Capacity to manage finances

Financial capacity is an important aspect of individual autonomy. Financial capacity differs from medical decision-making capacity, because it’s range is broad from pragmatic, conceptual and judgment abilities, while medical decision-making capacity is largely a verbally mediated capacity. Studies have shown that financial capacity is an advanced activity of daily living in older adults. This is also called an instrument activity of daily living. Instrumental activities of daily living are different from household activities of daily living, like shopping and preparing meals and basic activities of daily living, like dressing and walking. Financial abilities are broad and range from basic skills of counting coins to conducting transactions, balancing a check book and executing a will to higher level abilities of deciding on investments. Financial abilities vary across individuals and it depend on the person’s occupational history, socioeconomic status and overall financial experience.

Although financial capacity is important, there have only been a few working conceptual models of financial capacity. One model that combines clinical aspects and cognitive neuropsychological aspect contains three elements:

1. Declarative knowledge: the ability to describe facts, concepts and events that relate to financial activities, like currencies and concepts like rate or loans.

2. Procedural knowledge: the ability to carry out motor based, practical financial skills, like writing checks.

3. Judgment: the ability to make financial decisions that are consistent with one’s self-interest. This is the case for everyday and new situations.

This model sees financial capacity at three levels: specific abilities, broader areas of activity and overall financial capacity. Only recently has empirical research in the area of financial capacity in older adults emerged. Research that has been conducted has shown that the financial skills of patients with Alzheimer’s Disease are impaired relative to healthy older people. People with mild Alzheimer’s Disease show a deficit in different complex financial abilities and in almost all financial activities. People with moderate Alzheimer’s Disease show a loss of both complex and simple financial abilities and they also show an severe impairment across all financial activity. Research has also found that people with other forms of dementia show impairments in their financial abilities.

Capacity assessment these days

Capacity assessment will become more and more important. This is because of the ageing society. And of course, we are interested in being able to discriminate between impaired and intact function in older adults. There is an increase in longevity, dementia, transfer of wealth between generations and blended families and this will make issues of capacity loss in older people a public policy concern. The past decade capacity assessment in aging as a field of study emerged, as well as promising capacity assessment instruments. There are certain key areas that need more attention. One of these is the assessment of capacity to live independently. This capacity is so broad, that it can include almost all areas of functioning. Another area that deserves and is getting more attention (because of blended families and transgenerational transfer of money) is testamentary capacity and the exploitation of older adults with diminished capacities. A new concept in this field is undue influence, which means that some form of coercion of a vulnerable adult to do something that will benefit the coercer. Sadly, there is an increase in the undue influence cases and there is very little literature or knowledge from the psychological field to draw upon. There are two other areas that are almost without study. These are sexual consent and voting capacity. Can people who have a cognitive impairment vote correctly and consent to having sex with somebody? More research is needed.

Looking at a wider range of capacities is not the only thing that is needed. Researchers should also look within a wider range of older patient groups. Studies should also focus on capacity impairment within dementia subtypes and also look at other neuropsychiatric illnesses, like schizophrenia and depression. Research should also look at capacity issues in developmental disorders, like autism and mental retardation. Studies should also look more into clinical decision making. We should know how clinical judgments of decisional capacity relate to the social dynamics of decision making. These studies should also look how clinicians from different disciplines may vary in their capacity assessment approach. Research should also look into identifying behavioural and cognitive markers of diminished capacity. There must be a solid empirical research base to ensure the accuracy and quality of capacity determination. The clinician’s opinion is currently the accepted clinical standard for capacity determination, but clinical judgments of capacity can be inaccurate, invalid or unreliable. Therefore, capacity assessment training should become a part of the clinical training of physicians, psychologists and other health care workers. Studies should also look at the relationship between legal and clinical models of capacity.