Modern medical ethics are built upon the concept of informed consent. This is not, however, as straightforward a concept as it may seem.

Physicians and health care providers have a duty to provide informed consent to their patients or their patients’ guardians, which means that they have to inform them appropriately about the risks and benefits of their recommendations and interventions. This includes informing them about the risks of not treating an illness.

This principle is, in turn, based largely upon the principle of autonomy – people have the right to control their own lives, and one cannot have control without information.

This is all simple enough, but where it becomes tricky is in deciding how much information to give patients, and how to present it.

A recent study looks at how physicians talk to vaccine-hesitant parents about vaccinating their children. The study found two interests things – the first is that when physicians began their discussion with, “Your child needs to get his shots,” (presumptive style) the success rate (percentage of hesitant parents who accepted vaccines) was significantly higher than when they began, “what do you want do to about giving shots?” (participatory style).

In both cases physicians were meeting both the letter and spirit of the requirement for informed consent, and parents ultimately made the decision. The difference was in presentation style. Therefore, within the parameters of ethical informed consent, there is wide room for different behaviors that have a significant effect on the ultimate decision made by parents.

One might think of this as manipulative, which is true in the trivial sense that all social interaction is potentially psychologically manipulative. In any case, no one style is objectively more ethical than the other, and both have a psychological effect on decision-making.

This brings up the deeper point – is the duty of the physician only to provide information or is it also to steer their patient toward what they think is the best decision? How much “steering” is ethically acceptable? At some vague and fuzzy point a recommendation becomes pressure, and at some point pressure becomes unethical.

I don’t think the presumptive approach constitutes undue pressure. It is simply one way of a physician to state their recommendation, which is as much part of their duty as informed consent.

Let me give another example – how much do you disclose to patients about your differential diagnosis? It’s generally accepted that you do not mention the most horrible and scary things on the list up front, especially when they are unlikely. If a patient presents to me with headache, it is very unlikely that they have a brain tumor. Still, if they meet criteria, I will order imaging to rule out a tumor or other underlying cause. What if the patient refuses imaging?

Certainly I am not going to tell every one of my headache patients that there is a very small chance they may have brain cancer. I’ll just get the MRI scan and rule it out. This is a case in which giving a patient more information will only serve to cause unnecessary anxiety. But if the patient refuses imaging, for whatever reason, then my duty changes. Now I have to tell them how important it is that we image their brain. I am, in fact, obligated to keep increasing the amount of information I give the patient to more and more scary details until either they agree to the scan or I have done everything I can to convince them to get it.

Style and context therefore matter to informed consent. Another significant factor is – how much information is enough? When I prescribe a drug to a patient I discuss with them common side effects, any potentially serious side effect, and other options, including not treating at all. However, I have to choose from professional experience and judgement which details are important. There are not enough hours in the day, let alone time in an office visit, to discuss the entire list of potential interactions and side effects of every possible treatment option. To some extent the patient relies upon the physician to hit the highlights.

If the patient is still uncertain, or they want more information, then I can direct them to the package insert or to online information where they can read up to their heart’s content all the information they want. I can then help them put that information into clinical perspective.

Also – and this is very tricky – it is possible that more information may cause unnecessary anxiety and actually confuse decision-making. Marketing research shows that people want choices and information, but too many choices and too much information causes anxiety and paralyzes their decision-making.

In the context of medicine, a patient may read about a rare but scary side effect of a medication and decide not to take it, even though the risks of not taking the medication vastly outweigh the risk of that potential side effect. People do not necessarily weigh risks rationally.

This brings us to the ultimate context of this topic of informed consent – the notion of informed consent assumes that people are rational actors who will make the best decisions in their own self-interest if they are properly informed. I agree, from an ethical standpoint, this is a reasonable approach.

However, a century of psychological research has shown that this is not true. People are not rational actors, we are psychosocial actors. We make decisions from a host of cognitive biases, motivations, and social influences. This includes, most pertinent to medical decision-making, risk aversion and loss aversion. People, for example, may expose themselves to a greater risk because they are averse to a much smaller but psychologically more dramatic risk.

The role of the health-care provider in terms of informed consent, therefore, is not only to provide raw information to their patients but to present it in a way that puts that information in the proper context, including psychological context. The physician is the lens that puts that information into proper scale and focus.

Of course, for this to be the case the physician has to first have the information in proper context, which means stepping back from all the cognitive biases of human psychology and looking at the information from a rational and statistical perspective. Physicians have to understand their own psychology and biases as well as those of their patients.

In short, good physicians need to be skeptics. Informed consent requires nothing less.

Posted by Steven Novella

Founder and currently Executive Editor of Science-Based Medicine Steven Novella, MD is an academic clinical neurologist at the Yale University School of Medicine. He is also the president and co-founder of the New England Skeptical Society, the host and producer of the popular weekly science podcast, The Skeptics’ Guide to the Universe, and the author of the NeuroLogicaBlog, a daily blog that covers news and issues in neuroscience, but also general science, scientific skepticism, philosophy of science, critical thinking, and the intersection of science with the media and society. Dr. Novella also contributes every Sunday to The Rogues Gallery, the official blog of the SGU.