Informed consent. In my experience, capacity to give informed consent is the most commonly requested specific capacity assessment in general medical settings. Informed consent must be knowing, voluntary, and competent. All material information—information that would cause a reasonable person to accept or reject a proposed treatment—should be communicated to the patient. Informed consent requires an understanding of the patient’s condition and indication for treatment, risks and benefits of and alternatives to treatment, and risks of declining treatment.2,3 Exceptions to informed consent include incompetence, medical emergencies, patient waiver of informed consent, and a limited therapeutic privilege (when a physician determines that the information would harm the patient).3
Several instruments can help clinicians assess patients’ capacity to give informed consent. The benefits of using a structured instrument include:
- ensuring that specific information is covered during each evaluation
- systematically recording a patient’s response.5
Disadvantages of using instruments include the fact that no instrument can take into account all aspects of a particular case, and some instruments are time-consuming and require training. Structured instruments can be a useful adjunct to the clinical interview in some cases, but should not substitute for it. In a review of 23 instruments for assessing decisional capacity to consent to treatment or clinical research, the MacArthur Competence Assessment Tool for Clinical Research and the MacArthur Competence Assessment Tool for Treatment had the most empirical support, although the authors noted that other instruments might be better suited to specific situations.7
Psychiatrists may be consulted when a patient refuses treatment or decides to leave the hospital against medical advice. The key issue in both situations is whether the patient has capacity to refuse treatment.8 If there is evidence that the patient is mentally ill and poses an imminent risk of suicide or violence or is unable to provide for his or her basic needs, the psychiatrist should assess whether the patient meets criteria for civil commitment.
Many clinicians employ a “sliding scale” approach to competence, requiring a lower degree of competence for consenting to low-risk, high-benefit interventions and a greater degree of competence for higher-risk procedures.5,9 Family members often serve as informal surrogate decision makers for incapacitated patients, except when there is significant family discord or no family members are available.5
Guardianship. Guardians are appointed by courts to make decisions for individuals who have been found incompetent (wards). Although its purposes are beneficent, the guardianship system could do significant harm.10 Determining that an individual is incompetent is tantamount to depriving him or her of basic personhood. In many cases, the ward loses the ability to consent to or refuse medical care, manage his or her finances, enter into contracts, marry, and determine where he or she will live. On the other hand, failing to recognize incompetence can leave a vulnerable person in danger of physical deterioration, abuse, neglect, or exploitation.
It is critical that guardianship evaluations be conducted carefully. In a review of 298 guardianship cases from 3 states, Moye and colleagues11 found that the quality of the reports was significantly better in Colorado, a state with guardianship reforms, but documentation of functional strengths and weaknesses was “particularly rare” in guardianship evaluations and prognosis often was not included. This information is relevant to judges, who need to determine which areas of function are impaired and how long the impairment is likely to last.
Guardianship evaluations often focus on general rather than specific capacity. In other words, often there is not a specific task such as consenting to surgery that the alleged incompetent person needs to perform. Rather, the question is whether an individual can manage his or her finances or make treatment decisions in general. Appelbaum and Gutheil suggest considering 6 factors when assessing general capacity:
- awareness of the situation
- factual understanding of the issues
- appreciation of the likely consequences
- rational manipulation of information
- functioning in one’s environment
- extent of demands on patient.5
The first 4 are closely related to the elements of specific capacity described above. Functioning in one’s environment and extent of demands on the patient attempt to anticipate the tasks that an individual will need to perform. A patient with mild dementia may be unable to manage a complex estate but can handle a bank account and a fixed income. Similarly, it is important to consider the patient’s support system. An impaired patient may function adequately with his wife’s help but may lose the capacity to live independently if his wife dies or becomes impaired.