Have you ever wondered why it is that two different doctors, presented with the exact same information, would come to two entirely different conclusions? Whether they’re evaluating a medical study or determining the safest option for treatment, medicine is rife with disagreement. And hearing differing expert opinions can make a decision even more difficult for a patient considering whether or not to undergo a procedure, take a medication or decide between competing options to treat a disease (or the risk of one). We know that the science is uncertain, but why can’t experts make up their minds?

I’ve assumed in the past that this had to do with people’s respective medical backgrounds, or perhaps one expert isn’t as up-to-date on the latest research or as experienced as the other. But while attending the Health Journalism 2013 conference in Boston last month, I heard endocrinologist Pamela Hartzband and oncologist Jerome Groopman present a different case while speaking to a packed auditorium of conference attendees. Even though they both attended Ivy League medical schools, completed their residencies at Massachusetts General and eventually got married, their opinions on medical treatments are as different as night and day.

Why is that? Groopman and Hartband actually discussed their different temperaments in a book they co-wrote, Your Medical Mind: How To Decide What’s Right For You. In the book, and the talk they gave, they define four different temperaments that affect the way decisions are made and information is interpreted—both in a patient and in a healthcare worker. While these temperaments can change situationally and over time, being aware of the fact that people view medical decisions through these frameworks was eye opening.

Doubter vs. Believer

Many of us start out as believers, with an inherent trust of the medical system. We do what our doctors tell us and believe strongly that any medication we are given or procedure we go through will have great results. Believers strongly feel that there is a successful solution for each problem.

Doubters may have had a bad experience with the medical system, or may simply have a distrusting disposition. These are our skeptics, people who are more risk-averse, and who weigh the potential side effects of a drug carefully before choosing whether or not to take it. Sometimes, doubters believe, the benefits do not outweigh the costs. A doubter, especially a minimalist doubter (we’ll talk about that next) won’t immediately reach for over-the-counter meds in the event of a headache.

Maximalist vs. Minimalist

These are your ‘more is better’ folks. The maximalist wants the doctor to do every possible thing to treat a medical condition or even risk factors. They’re not satisfied being at the cutoff for healthy blood pressure numbers, for example. They want to be right in the middle or towards the healthiest range, and are willing to take extra medication to do it, despite additional side effects.

Minimalists look at side effects of drugs closely. They sometimes ask if they can take lower amounts of a given medication, believing that less is more. They avoid treatment whenever possible, since they believe that the side effects or other complications can be far more risky than the benefits offered.

Technologist vs. Naturalist

We all know naturalists. They’re the people extolling the virtues of white willow bark, which contains salicylic acid, an early form of aspirin. They will explain all of the benefits of using chemicals derived from plants, rather than synthetic versions made in a lab. When naturalists are also maximalists, they’ll have a fridge full of natural supplements and appointments with acupuncturists, naturopaths or herbalists. Naturalists who are also minimalists may be less likely to follow through on a treatment protocol, even an herbal one, or they’ll take lower doses of a drug than recommended. In general, naturalists are orientated towards allowing the body to cure itself, whether they decide to do so with medical intervention or not.

Technologists are the people who would rather use the synthetic version of a drug found in a plant, even after knowing that the ingredient is chemically identical. They have an inherent trust towards cutting-edge science and technology. They may want to try an experimental treatment, forgoing any risks involved for the perceived benefits of being an early adopter. If they’re maximalists, they may be interested in innovative new procedures even if they’re not yet recommended. Technologists are more likely to embrace a new medication if the last one didn’t work or had side effects.

(A chart of the different medical mindsets listed above, compiled by Laurie Levy and Kim James, is available online)

Now What?

Those of you who know me well could probably guess my medical disposition. I am a doubter, and a minimalist with a disposition towards naturalism. I avoid doctors whenever possible, and let them know in advance that I may not fill certain prescriptions. Good physicians work with me, explaining the different options and letting me make an informed decision. For my part, I need to make sure not to automatically assume the worst in any given situation; to actually look at the information in front of me instead of relying on anecdotes from friends or online.

On the opposite spectrum, a believer who is a maximalist with a technology orientation may need to temper their expectations of a given treatment based on the information available, and also look at the information in front of them rather than relying on raving testimony of just a few individuals.

Analyzing Information

But if your mindset automatically skews your judgment in a certain way, how do you even look at a difficult decision in a more rational way? After all, even medical experts looking at the same data from the same clinical study, and with knowledge of the same risks and benefits, often see things in a way reflecting their own mindset and preferences.

Here are a few strategies using numbers and statistics, as presented by Groopman and Hartband in their talk and in their book.

• Know the number needed to harm and the number needed to treat. The number needed to harm will tell you how many patients have to be exposed to a risk factor to cause harm in a single patient who would not otherwise have been harmed. The number needed to treat is an average number of patients who need to be treated to prevent one additional bad income. Although some debate exists about using these numbers for decision-making, combining research and statistics with anecdotal evidence can help you make more informed choices.

• Flip the numbers. Whether you’re looking at the success rate of a treatment or the percentage chance that a current condition will lead to further problems, it’s important to see how the numbers are framed and to flip them. For example, if you know that 25% of all people are cured using a specific therapy, it’s equally true that 75% of people die even with the therapy. Knowing that a drug works in the majority of patients is different than hearing that 49% of the people given that treatment do not respond to it.

• Contextualize the stories you hear. Using the numbers as a backdrop, now look at the anecdotes you’ve compiled in context. Although science is uncertain and decisions are often not clear-cut, looking at information in context may help make decisions a little bit easier. Beware the tendency to seek out stories to confirm what you already believe, amplifying your pre-existing mindset. Instead, seek to integrate the stories you hear into a wider body of information you’ve compiled.

• Be aware of grey areas. Recommendations from committees of experts change regularly. Expert opinions are often overturned. Guidelines often have a subjective component, and physicians from different countries or cultural backgrounds have different opinions on when benefits of a treatment outweigh the risks.

• Dispositions change. Even a naturalist who is a minimalist and a doubter may eagerly line up for the latest exploratory treatment when diagnosed with a particularly harrowing condition. And a maximalist who is a believer and has a technology orientation may decide they have tired of surgeries and medications. Your own circumstances can drastically change the way you approach medical care.

For more information, check out Dr. Groopman and Dr. Hartzband’s book, Your Medical Mind: How To Decide What is Right for You.