Evidence-based medicine


Shared decision-making

Martin (Marty) Mayer, DMSc, MS, PA-C

What is evidence-based medicine (EBM)?

Contrary to what some may think, EBM is not "one size fits all" medicine dictated by data, research, or statistics. Evidence certainly plays a pivotal role in EBM (hence the name), but evidence by itself is never enough.

In 1996, Sackett and colleagues offered a great description of what EBM is and what EBM isn't, and their description remains just as accurate today as it was when they published it. Importantly, true EBM is medicine that utilizes the best-available evidence, clinical expertise, and – of great importance – a patient's values and preferences. It is only when these three elements are working together to the fullest extent possible that one is truly practicing EBM. Therefore, true EBM helps ensure optimized and individualized decisions for each patient based on the best-available evidence, clinical judgment, and the patient’s values and preferences.

Okay, then what is shared decision-making (SDM)?

In the simplest sense, it's the "patient's values and preferences" part of EBM. Therefore, arguably, SDM is a necessary part of EBM. However, SDM is often discussed as an individual topic, so I also emphasize both in line with that convention.

"Nothing about me without me" is perhaps the simplest and most potent conceptualization of SDM, coming from Valerie Billingham in 1998 during the Salzburg Global Seminar Session Through the Patient's Eyes: Collaboration between Patients and Health Care Professionals. Additionally, although not speaking directly to SDM, Robin Williams as Patch Adams in the namesake movie offered a poignant portrayal of the heart of medicine and the importance of maintaining proper focus (i.e., remembering patients are people, not just diagnoses or chief complaints); this was perhaps best expressed during a portion of the film when he offered the profound sentiment: "You treat a disease, you win, you lose. You treat a person, I guarantee you, you'll win, no matter what the outcome." This mindset is crucial to SDM. I have described SDM as "a partnership between the [clinician] and patient that involves: (1) informing the patient about his/her condition(s) and the evidence surrounding the treatment options available, (2) informing the patient in a manner that is understandable to him/her, and (3) exploring and respecting the patient's values and preferences in order to reach a personalised, informed decision regarding the best approach for his/her particular case." Although it's much wordier than Billingham's quote, I feel this is also a good "nutshell" definition. Another good description comes from the National Learning Consortium (of the Office of the National Coordinator for Health Information Technology): "Shared decision making is a key component of patient-centered health care. It is a process in which clinicians and patients work together to make decisions and select tests, treatments and care plans based on clinical evidence that balances risks and expected outcomes with patient preferences and values." There are also other resources available that offer additional insights into SDM here, here, here, and here.