Medical Practice

What is “Evidence-Based Medicine”?

By June 28, 2016 January 28th, 2020 No Comments

When patients go to a doctor, they want the best possible diagnosis and treatment. But how does that doctor know exactly what to do in any particular circumstance?

Medical school (of course) is the first part of the answer to this question. Clinical experience is the second part. This combination of formal training and day-to-day practice is what helps a physician to build the expertise and judgment they need to be good at their work.

However, even the very best education and most extensive professional experience cannot prepare a doctor perfectly for any situation. The simple truth is that the human body is so complex that no one physician can possibly know everything about it or about every health condition or potential treatment option. This is one reason that today’s doctors often choose to specialize, consult with each other and pursue continuing education. It’s also one reason why the healthcare community is working to pool its knowledge and develop treatment protocols based on its collective experience about what has worked best for patients in the past. This systematic approach is called “Evidence-Based Medicine”.

Evidence-based medicine has been described as “the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients.” Such evidence is based on randomized controlled trials to ensure an unbiased and entirely objective analysis of each study. The aim of evidence-based medicine (EBM) is to provide both quantitative and qualitative assistance in the clinician’s decision making process.

Proponents of the EBM approach realize that no system is perfect for all cases. They know that patient preferences and values can play an important part. They know, too, that not every patient is going to fit into the definitions described by a randomized controlled trial. Individual pathology and physiology may differ and not every patient will respond to the same treatment.

Trisha Greenhalgh and epidemiologist Anna Donald extended and clarified the EBM definition. They wrote that evidence-based medicine is, “the use of mathematical estimates of the risk of benefit and harm, derived from high-quality research on population samples, to inform clinical decision-making in the diagnosis, investigation or management of individual patients.”

One of the key objectives of EBM is to help make medical decision-making more objective in order to achieve better results for each individual patient.

The concept of evidence-based medicine has gained wide acceptance in most parts of the healthcare community. However, it does also have its practical limitations.

  • The results upon which EBM is based may not prove relevant in all situations. This is because much of the quantitative research produced by EBM depends on randomized controlled trials (RCTs).
  • Not every medical problem has been thoroughly investigated, making the body of evidence incomplete.
  • Certain groups remain under-researched, and thus generalizing from RCT findings becomes imperfect at best.
  • Research topics are strongly controlled by the sponsor’s interests. After all, RCTs are expensive and are rarely, if ever, conducted on methodologies that possess little or no profit incentive. In other words, traditional, alternative and holistic approaches remain largely under-represented.
  • There is always a delay—sometimes substantial—between the time an RCT is conducted and the actual publication of its findings.
  • There is also a delay between the publication of RCT results and the proper application of those results.
  • Some corporations have stifled the publication of RCT findings when the results proved detrimental to the public view of one or more of their products. This becomes particularly problematic when a former employee of the corporation in question becomes an editor at the peer-reviewed journal which would carry those research findings. Such corporate intervention jeopardizes not only the integrity of the body of scientific evidence, but also jeopardizes the health of the patients which EBM is supposed to benefit.

While evidence-based medicine certainly presents its share of challenges, it’s the best hope we have today for applying our growing body of healthcare experience to individual cases. As researchers and clinicians continue to collect data and make it more widely available and easier to access, EBM will offer more opportunities for physicians to treat their patients based on the best, most up-to-date information.