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  • Writer's pictureRajani Katta MD & Jenny Li-Wang BA

Introduction to Basic Medical Ethics for the Casper Test, MMI, and Medical School Interview

Updated: Aug 25, 2022

Introduction To Basic Medical Ethics

Here's what one of my students once asked me: I'm not in medical school yet! Why do I need to know about medical ethics?

To start with, you may be asked questions related to medical ethics during your interviews. As a medical school professor and the creator of the course Medical School Interviewing 101, I've worked with many premedical and medical students...and this is an area where prior experience or common sense just isn't enough. You need to learn the vocabulary and be able to discuss concepts such as autonomy and non-maleficence.

Beyond the interview, medical ethics play an integral role in how we provide medical care, and medical schools have a strong interest in ensuring our nation's future physicians have a strong grounding in these principles.

If you're looking for more help applying to medical school, we offer our online course Medical School Interviewing 101. Our expert strategies and insider tips on the admissions process can help you become a standout applicant.

What are medical ethics?

Medical ethics are the values, beliefs, and principles that help us practice moral medical care.

Health care workers make difficult decisions every day regarding the health of their patients, themselves, and general society. While medical ethics don’t necessarily offer direct solutions, they can help decision-makers better understand the different ethical considerations at play in a challenging situation.

Why do premed and other pre-professional students need to learn the basics of medical ethics? It’s because medical schools and other professional schools want to know that you can approach patient care and the many complex issues that arise during patient care in a professional and ethical manner.

How do medical schools evaluate your ethical decision-making skills? Some do it via the traditional medical school interview, others via the MMI (Multiple Mini Interview), and others via the Casper test.

While learning the basics of medical ethics will help you in interview prep, they’re critical in understanding many of the issues that you’ll eventually face in your medical career.

Image of student learning about medical ethics before interview
Learning the basics of medical ethics will help you prepare for your medical school interview or MMI

While we provide an overview of basic medical ethics below, you can also hear a quick explanation of these principles by listening to two of my podcast episodes on this topic. These are episodes that were recorded for the Step 2 Success Podcast, which is used to help medical students prepare for the USMLE step 2 exam.

What are the main principles of medical ethics?

There are four main principles which should govern medical decision-making:1

1. Respect for autonomy

2. Beneficence

3. Non-maleficence

4. Justice

Some call these principles prima facie, which basically means “the principle is binding unless it conflicts with another moral principle—if it does we have to choose between them.” In essence, although these are the main principles underlying the practice of ethical medical decision-making, it’s important to recognize that sometimes these principles will contradict each other. Oftentimes, the most difficult situations will force you to decide between multiple potential courses of action, each with their own associated advantages and disadvantages.

In the setting of an exam, if you were presented with a case that just focused on patient autonomy, it would be easy to decide the best course of action. However, most interview and exam cases are designed to place different ethical principles in tension. For example, a classic ethical dilemma for doctors lies in end-of-life care. When is it acceptable to stop treating a patient? When, if ever, is it acceptable to let a patient die?

In your responses, it’s important to understand and then verbalize the principles that are involved. Then, you should identify any conflicts between these principles.

The Four Core Principles of Medical Ethics

1. Respect for autonomy

Respect for autonomy (in the most basic medical terms) means that in our healthcare system, adult patients get to decide what happens to their bodies.

Autonomy is defined as the capacity to “make our own decisions on the basis of deliberation.” Respect for autonomy is “the moral obligation to respect the autonomy of others in so far as such respect is compatible with equal respect for the autonomy of all potentially affected.”

  • How do healthcare workers uphold the principle of autonomy? Informed consent and patient-physician confidentiality are two examples.

  • Autonomy is applicable to adult patients who have the capacity to understand and make decisions. It’s important to note that patient autonomy refers very often to only adults and those with capacity. We’ll discuss these concepts more later on.

Example of a dilemma that centers on patient autonomy vs public health:

  • An elderly patient comes to you to ask for a doctor’s note exempting her from wearing a mask in public. She says wearing a mask is difficult due to her COPD. What would you do for this patient?2

2. Beneficence

Beneficence refers to the obligation of doctors to provide “net benefit to patients.”1 This means that doctors must act in their patient’s best interest at all times.

3. Non-Maleficence

Non-maleficence describes the obligation of doctors to perform care “with minimal harm.”1 This is the principle of “first, do no harm.”

It’s crucial to practice beneficence with non-maleficence. Most medical interventions are associated with benefits as well as risks. Physicians need to weigh multiple factors in order to decide the best course of action to recommend to the patient.

Example of a dilemma that highlights the tension between patient autonomy and non-maleficence:

  • A patient needs surgery that may require a blood transfusion during the operation. However, the patient is a Jehovah’s Witness and requests that no blood transfusions be administered, regardless of medical risk. How would you respond to this patient?3

4. Justice

Justice is about making our healthcare system fair. Issues of fairness in medicine include problems such as how to ensure accessibility to medical care and how to distribute resources in a fair manner. Public good is a concept closely related to justice. It’s important to recognize that justice is not only about individuals, but also about the safety of society.

Example of justice dilemma:

  • A hospital ICU is reaching capacity due to a surge in COVID-19 patients. Hospital administrators must begin to prioritize patients who receive ICU beds. How would you go about prioritizing patients for ICU beds?4

An Overview of Common Tensions in Medical Ethics

The Tension Between Autonomy and Beneficence

In general, autonomy will take precedence over beneficence when the patient:

  • Is an adult

  • Has the mental capacity to understand and communicate medical decisions

Doctors have an obligation to provide the best care to their patients without harming them (beneficence). However, they must also respect the decisions of fully-informed and mentally capable patients (autonomy).

What does this mean? It means that if an adult patient (with capacity) does not want to undergo a medically necessary treatment, then healthcare workers must defer to their decision and respect their autonomy. For example, if a woman with breast cancer decides to forgo all cancer treatment, and she understands the consequences of refusing cancer treatment, then the healthcare team must respect that decision. Having said that, the healthcare team can, and should, follow-up with the patient and support her in other ways.6

The Tension Between Autonomy and the Public Good

The COVID-19 pandemic is an excellent example of how challenging it can be to balance public health concerns with individual autonomy.

Different countries have used different approaches to address the pandemic. Almost globally, there’s been extensive discussion about the use of mask mandates, self-imposed vs. forced quarantine, and surveillance/tracking movements.7

An individual may assert their right to autonomy in declining to wear a mask, but the principle of autonomy needs to be weighed against the concept of the public good. During the pandemic, the tensions between these important principles have been brought to the forefront.

Another issue highlighted by the pandemic is that of vaccine distribution. Vaccine distribution brings up some important ethical issues, especially justice. Globally, less affluent countries are not receiving equitable access to COVID-19 vaccines. This access is further stratified by class and wealth within these countries. The WHO has proposed a strategy to increase global vaccine distribution through COVAX and AVAT, with a target of 40% vaccination rates in every country by the end of 2022.8

The Tension Between Patient Privacy and The Public Good

Patient confidentiality is a major tenet of healthcare. HIPAA, the Health Insurance Portability and Accountability Act of 1996, is a federal law that protects patient health information.

Examples of protected patient health information include:

  • Patient’s name and other demographic information

  • Details about a patient’s case

  • Patient’s diagnosis

  • Planned treatment

However, there are certain cases when it is permissible (and sometimes required) for healthcare workers to breach patient confidentiality. In these cases, it’s felt that the public good outweighs the right to privacy.

Examples of when doctors may breach confidentiality for the public good:

  • Reportable diseases

  • Child or elder abuse

  • Injuries that could relate to criminal conduct

By state or national law, doctors must report certain diseases to public health departments or the CDC.9 Reportable diseases include certain STDs, infectious diseases, and other illnesses that pose a significant public health threat.

Other Important Facets of Medical Ethics

The Decision-Making Powers of Adults vs. Minors

In general, adults get to decide what medical care they receive. Minors do not.

In the case of minors, parents are legally given the right to make medical decisions for their children, unless they keep their child from receiving a life-saving or crucial intervention.

Can minors ever receive medical care without parental consent? Yes, in certain specific situations. However, it’s important to remember that laws vary greatly from state to state.

In some states in the US, minors are allowed to seek certain specific services without parental consent. These include:

  • STD testing

  • Treatment for substance abuse

  • Outpatient mental health services

  • Contraception and pregnancy care

  • Abortion services

Ethical Considerations Regarding Patients with Capacity vs. Those who are Incapacitated

Capacity refers to patients who…

  • Can cognitively understand the diagnosis, prognosis, and risks/benefits of treatment and alternatives

  • Can make a choice about their treatment

  • Can communicate that choice

In contrast, incapacitated patients are patients who…

  • May have cognitive impairments which limit their ability to understand and communicate effectively (e.g. advanced dementia)

  • May have severe mental illness that impairs their decision-making (e.g. severe depression)

A patient is presumed to have capacity unless a doctor can demonstrate otherwise. How would a physician document a lack of capacity? This may be done either by testing or medical opinion.

What happens if a patient is incapacitated? In these cases, someone else is appointed to make their medical decisions. I’ll discuss this more later.

The importance of advance directives in medical decision-making

What are advance directives? These are legal documents that allow patients to make medical decisions “ahead of time” by detailing the care that they would want in case they ever become incapacitated.

Some important definitions and examples of advance directives:

  • Advance directive

A legal document that details what the patient would want in case they ever become incapacitated. These can be simple or as comprehensive as the patient wishes. In other words, a patient may decide to include directions about the use of CPR, ventilation, feeding tubes, or many other medical interventions. They may address one or many of these interventions in their advance directive.

  • Living wills

A type of advance directive that expresses what medical care a patient would or wouldn’t want.

  • DNR orders

A type of advance directive that states whether the patient would want to be resuscitated if their heart were to stop or if they were to stop breathing.

  • Durable power of attorney for healthcare

A type of advance directive that identifies the person that the patient chooses to make medical decisions on their behalf if they ever become incapacitated.

How do we make decisions for incapacitated patients?

There is a process for how doctors make medical decisions for patients who are incapacitated:

  • Last-known wishes

Assuming a patient had the mental capacity to understand and communicate, the patient’s last-known wishes about their own care should be followed. Last-known wishes take precedence over advance directives.

  • Living wills

If the patient’s last-known wishes are unknown, refer to the patient’s living will.

  • Family member/ loved ones

If there’s no advance directive about the particular medical issue or intervention, doctors may turn to a surrogate to make the decisions. Surrogates are members of the patient’s family or other loved ones who would know the patient’s wishes.

The order of medical decision-making power is assigned as follows: spouse, adult children, parents, siblings. If loved ones disagree on treatment, the next course of action is to consult the hospital ethics committee.

Who makes decisions for incapacitated patients without advance directives or surrogates?

Unrepresented patients are a vulnerable population in healthcare. Some estimate there may be over 100,000 unrepresented patients in the U.S. These are patients who have “no available friends or family to make medical decisions as ‘default’ surrogates.”

Unrepresented patients may be:

  • Homeless

  • Mentally ill

  • Those who do not have family or friends

  • Elderly individuals who have outlived family and friends

For these unrepresented patients, some believe doctors should take charge of the patient’s medical decision-making. Others believe hospital ethics committees should take this role. Although some laws require that ethics committees be involved in decision-making, not all require it.5)

Image of unrepresented patient in medicine
There may be over 100,000 unrepresented patients in the U.S.

The Bottom Line

There’s an infinitely large number of challenging scenarios in medicine. A general introduction to the main principles of medical ethics—respect for autonomy, beneficence, non-maleficence, and justice—will help you identify the main concerns and tensions in any situation.

Decision-making in medicine is often complex. The goal is not to have the perfect solution, but instead to carefully consider the implications of different courses of action and to then make a decision that aligns best with medical ethics.


Dr. Rajani Katta is the creator of Medical School Interviewing 101, the course that teaches students how to ace their interviews. She is also the author of the Multiple Mini Interview: Winning Strategies from Admissions Faculty, the Casper Test Prep Guide, and The Medical School Interview. Dr. Katta is a practicing dermatologist and served as a Professor of Dermatology at the Baylor College of Medicine for over 17 years.

Jennifer Li-Wang is the author of The Casper Test Prep Guide and a graduate of Rice University with a double major in English and the Study of Women, Gender, and Sexuality (SWGS). Jenny grew up in Los Alamos, New Mexico and in her free time enjoys reading and running her small crochet business.

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