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Overview of Medical Decision Making


Michael Joseph Pistoria

, MEng, DO, Lehigh Valley Hospital - Coordinated Health

Reviewed/Revised Aug 2021 | Modified Apr 2023

People and their doctors must make many decisions about medical issues. People must decide whether and when to see a doctor When to See a Doctor The decision regarding when to see a doctor or other health care professional may vary, depending on whether the visit is for preventive care (routine visits), for medical problems, or for an... read more . Doctors and other primary care practitioners (PCPs) must decide what to advise people to do in order to stay well or become well. They both must make decisions about which tests, if any, should be done and which treatment, if any, should be done.

Medical testing decisions Medical Testing Decisions Because many different diseases can cause the same symptoms, it can be challenging for doctors and other primary care practitioners to identify the cause. Doctors first gather basic information... read more and medical treatment decisions Medical Treatment Decisions Before recommending treatment, doctors weigh the potential risk of harm from a treatment against its potential benefit. (See also Overview of Medical Decision Making and The Science of Medicine... read more can be complex, and they require that doctors balance their knowledge of diseases, tests, treatments, and the individual person to help people meet their health-related goals. Making decisions about medical care is most effective when doctors and patients work together. The best and most appropriate decisions are reached when the doctor’s experience and knowledge of medicine are combined with the patient’s knowledge, wishes, and values.

Defining goals

Before doing complicated, expensive, and/or potentially dangerous tests, doctors typically have a detailed conversation with people regarding the goals of the diagnostic and treatment plan. The typical goals of a diagnostic and treatment plan are to identify and then cure a disease. However, it may not always be desirable to make a diagnosis. The following are just two instances in which this might be true:

  • People do not want treatment for a certain disease.

  • There is no good treatment for a certain disease.

For example, if a person in very poor health did not want to have chemotherapy or surgery if a cancer were to be diagnosed, it might not be appropriate for that person to risk the complications of an invasive diagnostic test, such as a biopsy, to diagnose cancer.

Sometimes people don't want to have a test because they are worried about the treatment for a disease. A common example is cancer, which often requires unpleasant and sometimes dangerous treatment. Doctors may remind people that they might feel differently if they knew they had the disease and that getting tested does not commit them to getting treated.

Similarly, people may not want to have tests for diseases that have no known treatment. An example is Huntington disease Huntington Disease Huntington disease is a hereditary disease that causes random, flowing movements that are involuntary and cannot be suppressed (called chorea). Sometimes a muscle or a group of muscles jerk... read more , which is an inherited, progressive, fatal neurologic disorder. Some people with a family history of Huntington disease would prefer not to know whether they have the gene that causes the disease. Other people would like to be tested to help guide life-planning decisions for themselves or family members, who also may benefit from genetic or other testing.

Doctors and other primary care practitioners must judge the potential effects on their patients of any diagnostic or treatment recommendations. They must help people weigh the consequences of overlooking a serious condition, even if the diagnosis is unlikely. The same type of reasoning is used in making treatment decisions. Doctors will probably not recommend treatments for people who have a mild condition if those treatments may have serious side effects. However, if the condition is grave but cure is possible, the doctor may advise people that the potential side effects may be worth the risk.

Problems may arise when doctors and the people they treat do not share the same perceptions of risk, particularly regarding treatment. A person who hears about a possible serious side effect of a drug may be very concerned, regardless of how rarely the side effect occurs. The doctor may not be as concerned if the possibility of that side effect is remote. Alternatively, the doctor may not understand that what might seem to be a relatively minor side effect for most people may cause great problems for a particular person. For example, a person who drives for a living may be more concerned about taking a drug that can cause drowsiness or that may be forbidden by regulations.

Often, the balance between the risk of the disease and its treatment is not clear-cut. A doctor may judge the risks—and benefits—of a treatment differently than the person being treated does. People should discuss these differences in judgment with their doctors. Understanding risks can also help a person weigh options. A doctor may outline several approaches and ask the person to help decide among them. By evaluating the risks of the various choices and then factoring in personal values, a person can make more informed choices about medical care.

People should also be clear in expressing their choices to their doctors, especially if they have conditions, such as a terminal illness, that may make it impossible for them to express their wishes at some point later on (see Advance Directives Advance Directives Health care advance directives are legal documents that communicate a person’s wishes about health care decisions in the event the person becomes incapable of making health care decisions. There... read more ).

Standard of care and second opinions

For symptoms and disorders for which many studies have been done, there is usually a standard of care. The standard of care refers to tests and/or treatments that doctors generally agree have proven effective and thus should typically be recommended to people.

However, there is not a standard of care for some disorders, particularly those that are complex and hard to diagnose and treat. There may be no standard of care because studies that have been done show different results or similar results with different treatments. Or there may be no standard of care for very rare diseases, because large clinical studies have not been done. When there is no standard of care, there is no one "correct" approach or treatment. One doctor might propose a treatment that is different from that proposed by another doctor. Either might be right, or both might be wrong.

The standard of care changes as new research is done. For example, in the past, doctors gave a drug called lidocaine to every person who had a heart attack. Giving lidocaine was the standard of care because studies had shown that it helped prevent a potentially fatal heart rhythm disorder called ventricular fibrillation Ventricular Fibrillation Ventricular fibrillation is a potentially fatal, uncoordinated series of very rapid, ineffective contractions of the ventricles (lower chambers of the heart) caused by many chaotic electrical... read more Ventricular Fibrillation . However, studies later showed that even though lidocaine helped prevent ventricular fibrillation, people with heart attacks who were routinely given lidocaine were more likely to die. Then the standard of care became not to give lidocaine routinely.

When there is no standard of care, particularly with rare or serious disorders or with disorders that have not responded to treatments, people may also want to consult with another doctor, particularly one who has additional expertise (that is, get a second opinion Getting a Second Opinion Despite many similarities in training, doctors may vary in their opinions about how to diagnose or treat certain disorders. Such differences can occur among the best of doctors. Differences... read more ).

Information sources for doctors

Most doctors rely on their education and experience: what they have learned from their training, from their colleagues, and from diagnosing and treating people with similar problems. Doctors also read medical books and journals, consult with colleagues, and refer to other resources, such as authoritative health websites, to get more information about specific problems and to keep up with new information generated by medical research. They also review recommendations (practice guidelines) published by groups of experts.

As new research findings are published, doctors evaluate the studies and consider how their findings might best be applied. Different types of studies provide different types of information. However, while research studies provide information only about the average risk of harm and benefit, the average effects do not always tell doctors how a particular person will respond to a treatment.

A clinical trial is considered the most accurate type of study. In a controlled clinical trial, people entering the study are divided randomly (by chance) into two or more groups. One group of people receives a particular treatment or test, while the other groups (called control groups) receive different treatments or tests or no treatment or test at all. The random assignment ensures that the different groups are as similar as possible. That way, any difference in outcome is likely to be due to the treatment or test being studied rather than to an underlying and potentially unknown difference between the groups. Researchers try to design trials so that people being studied, as well as the investigators themselves, do not know which group is getting what treatment, a process called double-blinding. This decreases the likelihood that someone's expectations might affect the results.

Information sources for people

Although many people rely solely on their primary care practitioners for information, it is often helpful for people to obtain additional information about a recommended test or treatment before making a decision (see Researching a Disorder Researching a Disorder When a disorder is first diagnosed, the doctor or other health care professional often gives a handout that summarizes key points of information. (See also Introduction to Making the Most of... read more ). Information can be obtained from

  • Pamphlets, brochures, and other materials doctors provide

  • Publications, such as books, newsletters, and magazines, designed to explain medical information to consumers

  • Credible online health resources

Did You Know...

  • The quality of medical information available on the Internet can vary greatly.

The quality of on-line medical information can vary greatly. Forums in which people describe their experiences with illnesses and provide suggestions can sometimes contain information that is inaccurate or even harmful. Other on-line resources may describe conspiracy theories or solicit money with promises of providing miracle cures that, in reality, have no benefit. When researching an illness or symptom, a person should seek information from reputable websites, such as those from major medical societies (for example, the American Cancer Society or the American Heart Association) or medical institutions. The following three reputable sources are particularly helpful:

A doctor can also help a person determine whether information found on the internet is accurate.

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