Informed Consent and the Patient’s Medical Capacity

Submitted by Vicki Conti, MD, Augusta Emergency Physicians

Informed consent includes four major components. The physician must disclose information to the patient; the patient must be able to understand the information; the patient must voluntarily grant consent without coercion; and the patient must have medical decision-making capacity.

The fourth and final item on that list is under primary consideration herein because the medical decision-making capacity of our patients is not always as clear cut as we would like it to be. This is evident in many distinct medical settings. Common examples include patients with cognitive impairment, mental illness or acute delirium (e.g. hypoxia, intoxication, acidosis). It can be especially difficult with patients that have chronic and progressive cognitive deteriorating conditions, such as patients with early dementia and patients with psychiatric diagnoses such as schizophrenia.

Adding to the complexity of our work, the family of the patient might have expectations for medical care that conflict with the patient’s wishes, thereby challenging the legal and ethical standards of our practice of medicine. In such situations the physician’s ability to establish capacity is of the utmost important. Just as we would be compelled ethically and medically to intervene in the decision-making process were an incapacitated patient try to make decisions that would be harmful to her, so, too, must we intervene when a family member attempts to contravene a patient’s lawful wishes.

To establish capacity, the physician must assess the following components of a patient’s decision-making capacity and ascertain if she has the following abilities.

  1. The ability to understand the medical condition and treatment options.
  2. The ability to appreciate how the options apply to their own treatment options.
  3. The ability to reason with the options available.
  4. The ability to communicate their decisions.

These four components allow a patient to retain her autonomy despite the physician’s recommendations. For example, ever if offered a life-saving blood transfusion, a patient who is a Jehovah’s Witness can refuse any blood products, as long as she is able to satisfy the aforementioned four components of capacity.

Moreover, it is important to recognize that capacity is not static. For example, a patient with dementia might be able to make decisions on a daily basis. However, if she presents to the medical establishment as acutely ill, e.g, with a urinary tract infection with delirium, then she at that point in time does not have capacity to make her own medical decisions. Conversely, we can never assume that a patient with a a diagnosis of dementia does not have capacity to make her own decisions.

As a final note, it bears mention, too that many times, and especially in emergency situations, the physician must make an immediate decision about a situation, and often the question of the patient’s capacity is not straightforward. In these circumstances we can not only follow the aforementioned guidelines, but also request the assistance of our colleagues in psychiatry.


  1. Howe, Edward, M.D., J.D. (2009). “Ethical Aspects of Evaluating a Patient’s Mental Capacity.” Psychiatry, 6(7),15–23.
  2. Jesus, John, M.D., Ed. (2012). Ethical Problems in Emergency Medicine: A Discussion-based Review, Hoboken: Wiley-Blackwell.
  3. Karlawish, Jason, M.D. (2017) “Assessment of Decision-Making Capacity in Adults.” UpToDate. [].
  4. Leo, Raphael J., M.D. (1999). “Competency and the Capacity to Make Treatment Decisions: A Primer for Primary Care Physicians.” The Primary Care Companion to the Journal of Clinical Psychiatry, 1(5), 131–141.
  5. Palmer, Barton W., []and Alexandrea L. Harmell [] (2016). “Assessment of Healthcare Decision Making Capacity.” Archive of Clinical Neuropsychol []ogy, 31(6), 530–540.