Informed Consent

Except under extraordinary circumstances, people have the legal right to make decisions about their bodies and their health care. Ideally, these decisions should be made by capable, informed individuals after discussions with their physicians, nurse practitioners, and other members of their healthcare provider team. This basic principle of informed consent is a legal and ethical practice that underlies health care and human research in the US. It is based upon our society’s respect for independence and self-determination for all.

Informed consent involves shared decision making:  The individual and the clinician each use their expertise to make healthcare decisions. The individual’s expertise is on their values, expectations, and goals of care and treatment; the clinician’s expertise is on diagnosis, prognosis, and treatment options.

What is informed consent?

Informed consent is a legal principle stating that people have the power to choose among medically reasonable plans for their healthcare. Carrying out informed consent requires effective communication between people and their healthcare providers.  It also requires that the individual be able to make informed choices and discuss many things, as often as needed, with the healthcare team. These include discussions about:

  • the diagnosis
  • the overall outlook (prognosis)
  • the nature of the recommended tests or treatments
  • the various treatment or care options
  • the risks and benefits of each option
  • likely outcomes of each option

Informed consent does not mean that an individual can or should dictate their care alone. If an individual asks for tests or treatments that the healthcare providers consider useless or harmful, they do not have to do so. The healthcare team has a duty to use their skills for the individual’s benefit and not to harm them. If people and their healthcare professionals disagree about the type of care someone should receive, they should discuss the situation further so their concerns are made clear and they can reach a decision that is mutually acceptable.

Informed consent is implied in a true health emergency, when consent from the individual or surrogate decision maker (the person who has been chosen to make decisions on the individual’s behalf) would cause a delay that would harm the individual.

Decision-Making Capability

There are several common misperceptions about people’s abilities to make decisions about their healthcare. For example:

  • If someone goes against the advice of their healthcare provider, they may still have the ability to make healthcare decisions.
  • Going against professional healthcare advice is not the only reason you might want or need to assess someone’s ability to make healthcare decisions.
  • If someone is not capable of making decisions in one area of life (for example, in their finances), they still may have the ability to make decisions in other areas of life. 
  • Individuals who are cognitively impaired may still be able to make their own healthcare decisions.
  • People who have a diagnosis for a psychiatric disorder may still be able to make their own healthcare decisions.
  • If people can’t make their own healthcare decisions at a particular point in time, they still may be able to make their own decisions again in the future.
  • There are several experts (not just mental health experts) who can assess if someone has the ability to make their own healthcare decisions.
The process of pursuing informed consent makes sense only for people who have the ability to make informed decisions. Adults are assumed to have this ability when they reach the age of majority.  In the US, this is 18 years of age. This does not change unless the individual is determined to be "incompetent or incapacitated" by a court of law. The terms "incompetent or incapacitated" are legal terms and they apply specifically to legal cases in court.

In practical terms, healthcare professionals are sometimes asked to evaluate an individual’s ability to make decisions. If the healthcare professional finds that an individual lacks the ability to make informed decisions about health care, that individual may be considered "incapable." This is significant because it means that decisions may then be made by someone other than the individual.

The term "diminished capacity" generally refers to specific types of decisions, not all decisions. For example, someone may be able to make decisions about their health care, but not about finances, or vice versa. This selective definition of capacity (often referred to as a "sliding scale") provides people with more protection and self-determination. Of course, people who are unconscious or severely mentally impaired may lack the ability to make any decisions.

Judging the capacity to make decisions

Medical decisions

We judge the capacity to make medical decisions based on a person's

  • ability to understand relevant information
  • ability to understand the consequences of the decision
  • ability to communicate a decision

Decisions of Self-Care

We judge the capacity to make self-care decisions based on a person's

  • ability to care for themselves
  • ability to accept needed help to keep oneself safe


We judge the capacity to make financial decisions based on a person's

  • ability to manage paying bills
  • ability to do calculations and keep track of money

Last Will and Testament

We judge the capacity to make decisions about a last will and testament based on a person's

  • ability to remember estate plans
  • ability to express logic behind choices
It's important to remember that the ability to understand situations may change over time. For example, someone with delirium may be mentally clear in the morning, but become confused in the evening.  Another example might be when someone has a high fever that can cloud thinking and makes them feel disoriented. When people are capable of making informed decisions, these choices should be respected. If there are times when someone is not capable of making informed decisions, decisions should be postponed if possible until they regain decision-making capacity.

People may be given standardized tests to check their mental status when their capacity is questioned by healthcare professionals. But, even if someone does poorly on a mental-status test or has impaired memory, they may still have the ability to make informed decisions. In these situations, extra attention may be needed to make sure they understand the risks, benefits, and consequences of the different healthcare options.

Additionally, don't confuse decision-making ability with so-called “rational” decisions. Decisions are often based on cultural, ethnic, or religious values and beliefs that vary from person to person. What is rational to one person might not seem rational to another. Requiring rationality would disqualify people who make highly personal or unconventional decisions. Beliefs that seem "unwise, foolish, or ridiculous" to others do not make a person incompetent.

If someone is determined to have the ability to make healthcare decisions, and is fully informed of the risks, benefits, and alternatives of a given treatment, they have the right to refuse that treatment, even if refusal of treatment may shorten their life.


Last Updated June 2017