Chapter 10: Decision-Making Capacity



Physicians must respect the autonomous choices of patients; however, illness or medications can impair the capacity of patients to make decisions about their health care. Such patients might be unable to make decisions, or their decisions contradict their best interests and cause them serious harm. Decision-making ability falls along a continuum, with no natural threshold for adequate decision-making capacity.

Nevertheless, for every patient a binary decision needs to be made: either a patient has adequate decision-making capacity and her choices should be respected, or she does not and someone else should decide [1]. The following case illustrates how it might be difficult to decide whether decision-making power should be taken away from a patient.

Case 10.1. Refusal to explain a decision

Mrs. C, a 74-year-old widow with mild dementia, is admitted for congestive heart failure and angina pectoris that has progressed despite maximal medical therapy. In the past 3 years, she has suffered two myocardial infarctions. Her physician recommends coronary angiography and, if possible, angioplasty.

Mrs. C recognizes her primary care physician, but seldom knows the date or the name of the clinic. She has forgotten to come to several clinic appointments. Her mental functioning gets worse when she is hospitalized. A nephew, her only relative, pays a woman to shop, cook, and clean house for her. He reports that Mrs. C enjoys watching television, attending the senior center, and sitting in the park.

When asked about her wishes for care, Mrs. C says that she wants to go home. After many discussions, the cardiology team convinces her to have the angiogram. On the morning of the procedure, however, she changes her mind, saying that she doesn’t want anyone to put a tube into her heart and that she has been in the hospital long enough.

Her nephew believes that angioplasty would be best for her, but is reluctant to contradict her wishes because she has always been independent and stubborn. Mrs. C is generally adverse to medical interventions. She refused mammography, even though she has a family history of breast cancer. She also refused treatment for a cholesterol level of 318 mg per dL.

The team asks a psychiatrist to see her. On a mental status examination, she does not know the date, the name of the hospital, or the city. She recalls only one of three objects and cannot perform serial subtraction. She refuses to talk further with the psychiatrist, saying that she is not crazy.

In this case, Mrs. C’s mental functioning is obviously impaired. Is it so impaired that her nephew should assume the authority to make medical decisions for her? Her refusal did not seem so unreasonable to some physicians and nurses. Furthermore, some nurses asked why her consent to angiography was not questioned, but only her refusal [2].

This chapter analyzes how physicians should assess whether patients like Mrs. C have the capacity to make decisions about their care. This book uses the term competent to refer to patients who have the capacity to make informed decisions about medical interventions. Strictly speaking, all adults are considered competent to make such decisions unless a court has declared them incompetent.

In everyday practice, however, physicians make de facto determinations that patients lack decision-making capacity and arrange for surrogates to make decisions, without involving the courts [3] – [6]. This clinical approach has been defended because routine judicial intervention imposes unacceptable delays and generally involves only superficial hearings. This book uses the phrase lacks decision-making capacity if a physician, rather than a court, determines that the patient is unable to make informed decisions about health care [3].

Ethical Implications of Decision-Making Capacity

Caring for patients whose decision-making capacity is questionable involves two conflicting ethical guidelines. On the one hand, physicians must respect the authority of competent patients to make decisions that others might regard as foolish, unwise, or harmful (see Chapter 11). On the other hand, physicians should act in their patients’ best interests (see Chapter 4). If patients who lack decision-making capacity make decisions that are contrary to their best interests, they need to be protected from serious harm [6]. The patient’s decision-making capacity is therefore crucial. If it is intact, then the patient’s decisions will be respected. If it is seriously impaired, then decision-making power is taken from the patient and given to a surrogate.

Generally, a patient’s decision-making capacity is not challenged if he or she agrees with the physician. On its face, this practice suggests that patients are only incapacitated when they disagree with physicians. It makes sense to raise more questions about decision-making capacity, however, when patients refuse a beneficial intervention than when they consent to it. When Mrs. C accepts angiography, her care would be the same whether or not she has decision-making capacity.

If she has adequate decision-making capacity, her consent to angioplasty would be valid. If she lacks it, her physician and surrogate agree that angiography was in her best interests. Now consider Mrs. C’s refusal of angiography (assuming that she had not previously given an informed refusal). If she has decision-making capacity, then her refusal would have to be respected. If she lacks it, then a surrogate would assume decision-making power. The physician and her nephew agree that angiography is in her best interests.

Hence, if she refuses, then her management hinges on whether her decision-making capacity is considered impaired. Thus, it is appropriate that Mrs. C’s refusal of recommended interventions triggers questions about her capacity to make medical decisions. Such a refusal, however, does not by itself prove that she lacks such capacity.

Legal Standards for Competence

The courts have not articulated clear standards for competency to make medical decisions [4], [5]. Many older legal cases viewed incompetence in general or global terms. Either the patient was competent in all aspects of life or the patient was not competent in any sphere. The courts inferred incompetence from a person’s overall ability to function in life, medical diagnoses, general mental functioning, and personal appearance.

In reality, a person might be capable of performing some tasks adequately but not others [6]; for example, a person might be capable of making informed medical decisions, but not informed financial decisions. A patient with Alzheimer disease who lacked capacity to consent to a clinical trial of a new drug may still have the capacity to appoint a surrogate to make decisions for them. Thus, it is more appropriate to consider a person competent or incompetent for specific tasks rather than in all aspects of life [5].

The modern legal and ethical consensus is that a person should be considered competent to make medical decisions if he or she is capable of giving informed consent [5]; that is, she appreciates the diagnosis and prognosis, the nature of the tests or treatments proposed, the alternatives, the risks and benefits of each, and the probable consequences. Chapter 3 discusses informed consent in detail.

Clinical Standards for Decision-Making Capacity

A patient’s decision-making capacity should be subjected to scrutiny in several situations. As in Case 10.1, the patient might refuse a treatment that the physician strongly recommends or vacillate in making a decision. In other cases, patients might have conditions that commonly impair decision-making capacity, such as dementia, schizophrenia, or depression.

Although these conditions justify closer scrutiny of the patient’s decision-making capacity, they do not necessarily impair decision-making capacity. Physicians need to test directly the individual patient’s ability to give informed consent for the proposed intervention [4] – [8]. Decision-making capacity requires a cluster of abilities (Table 10-1).

Table 10-1.Clinical Standards for Decision-Making Capacity

The patient makes and communicates a choice.
The patient understands the following information and appreciates its

  • relevance to the situation
  • the medical situation and prognosis
  • the nature of the recommended care
  • alternative courses of care
  • the risks, benefits, and consequences of each alternative
Decisions are consistent with the patient’s values and goals.
Decisions do not result from delusions.
The patient uses reasoning to make a choice.

The Patient Makes and Communicates a Choice

A patient must appreciate that he or she—and not the physician or family members—has ultimate decision-making power. In addition, the patient must be willing to choose among the alternative courses of care. A patient who vacillates repeatedly between consent and refusal is incapable of making a decision, let alone an informed one. Such profound indecision must be distinguished from changing one’s mind as the situation changes, as the patient receives more information or advice, or after the patient deliberates.

The patient must communicate his or her choice. A patient who is unable to speak because she is on a ventilator does not necessarily lack decision-making capacity. She might be able to communicate through writing messages, using an alphabet board, or blinking or nodding in response to questions.

The Patient Understands Pertinent Information and Appreciates Its Relevance

A patient needs to understand the medical situation and prognosis, the nature of the proposed intervention, the alternatives, the risks and benefits, and the likely consequences of each alternative. In addition, the patient needs to appreciate that she has the disorder and what the consequences of the intervention (or no intervention) would be for her. The patient needs to appreciate that the information that the physician discussed is relevant to her own situation. In Case 10.1, the health care team could not determine whether Mrs. C understood that angioplasty usually relieves chest pain, but has certain risks.

Decisions Are Consistent with the Patient’s Values and Goals

Choices should be consistent with the patient’s character and core values. If Mrs. C wants to be more active without pain, then refusing surgery or angioplasty would be inconsistent with her goals. Many patients, however, do not have well-articulated values and goals or might have multiple, conflicting goals. Mrs. C might want not only to return home but also to be more active and pain free. A choice might be consistent with some goals, but not with others.

People do not necessarily have a fixed hierarchy of goals and values. Mrs. C might define her goals or set priorities only by deciding about angiography. Thus, physicians should not regard a patient as lacking decision-making capacity merely because that patient cannot articulate a set of general values or goals.

Decisions Do Not Result from Delusions

Some patients have delusions that preclude informed decision making. Delusions are defined as false beliefs or incorrect inferences in the face of incontrovertible or obvious evidence to the contrary. For instance, Mary Northern was an elderly woman who refused amputation of her gangrenous legs, denying that gangrene had caused her feet to be “dead, black, shriveled, rotting and stinking” [9]. Instead, she believed that they were merely blackened by soot or dust.

The court declared her incompetent because she was “incapable of recognizing facts which would be obvious to a person of normal perception” [9]. The court said that if she had acknowledged that her legs were gangrenous but refused amputation because she preferred death to the loss of her feet, she would have been considered competent to refuse the surgery.

The Patient Uses Reasoning to Make a Choice

Processing information logically is another element of decision-making capacity. Patients should compare and weigh the various options for care [7]. This requirement does not require the patient to choose what most people consider reasonable in the situation. Unconventional decisions do not necessarily imply lack of decision-making capacity. Expectations for reasoning must take into account that many people do not deliberate, but instead rely on emotional or intuitive factors in making important decisions.