Assessment of decision-making capacity in adults
- Jason Karlawish, MD
Jason Karlawish, MD
- Professor of Medicine
- Medical Ethics and Health Policy
- University of Pennsylvania
- Section Editor
- Steven T DeKosky, MD, FAAN, FACP, FANA
Steven T DeKosky, MD, FAAN, FACP, FANA
- Section Editor — Dementia
- Professor of Neurology
- Deputy Director
- McKnight Brain Institute
- University of Florida College of Medicine
The capacity to make one’s own decisions is fundamental to the ethical principle of respect for autonomy and is a key component of informed consent to medical treatment. Determining whether an individual has adequate capacity to make decisions is therefore an inherent aspect of all clinician-patient interactions.
The main determinant of capacity is cognition, and any condition or treatment that affects cognition may potentially impair decision-making capacity. In the presence of cognitive impairment from any cause, determining whether a patient has adequate capacity is critical to striking the proper balance between respecting patient autonomy and acting in a patient’s best interest. A skillful capacity assessment can also help determine the severity of a patient’s cognitive impairments and improve the effectiveness of conversations with patients and their families.
These skills are especially important in the care of adult patients who have diseases that impair cognition. Patients with traumatic brain injury, psychiatric illnesses (eg, schizophrenia, bipolar disorder, and unipolar major depression), and neurodegenerative diseases (eg, Alzheimer disease and Parkinson disease) are at risk for impaired capacity. Hospitalized patients and older adults are also at risk due to cognitive impairment from chronic diseases, cognitive aging, and delirium.
This topic reviews the definition of capacity, predictors of impaired capacity, when and how to assess capacity, and how to incorporate an assessment of capacity into clinical judgments about the ability of patients to choose their treatment. Informed consent, advance care planning, advance directives, and medical decision making at the end of life are discussed separately. (See "Informed procedural consent" and "Advance care planning and advance directives" and "Ethical issues in palliative care" and "Legal aspects in palliative and end of life care".)
Capacity and competency — Capacity describes a person’s ability to a make a decision. In a medical context, capacity refers to the ability to utilize information about an illness and proposed treatment options to make a choice that is congruent with one’s own values and preferences.
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- Capacity and competency
- Informed consent
- How capacity differs from cognition and function
- FACTORS ASSOCIATED WITH IMPAIRED CAPACITY
- General principles
- High risk groups
- - Neurodegenerative disease
- - Psychiatric disorders
- - Traumatic brain injury
- - Hospitalized adults
- - End of life
- WHEN TO ASSESS CAPACITY
- HOW TO ASSESS CAPACITY
- The decision-making abilities
- - Understanding
- - Expressing a choice
- - Appreciation
- - Reasoning
- Semi-structured patient interview
- Validated instruments
- - Patient refuses a capacity assessment
- - Family does not agree with clinician’s assessment
- HOW THE CAPACITY ASSESSMENT INFORMS CLINICAL JUDGMENT
- WHAT TO DO WHEN A PATIENT LACKS CAPACITY