The terms “hospital medicine” and “evidence-based medicine” (EBM) are both recent arrivals in the history of medicine. Both have spread through medicine at a rapid pace, highlighting the attraction and fundamental soundness of their core ideas. Much has been written about the benefits of the hospitalist movement regarding quality, patient throughput and financial indicators. The next phase in the revolution of patient care is the confluence of technology, EBM, and hospital medicine. One of the pillars for the continued success of the hospital medicine movement will be EBM. EBM must become an integral part of the skill set for all hospitalists.
EBM is an analytical approach with a fundamental knowledge base and a set of tools. The exponential growth of clinical information requires that physicians use an analytical approach for answering clinical questions and keeping up-to-date. This may be easier if you work at an academic center rather than a non-teaching hospital, although this is not guaranteed. Regardless of the working environment, an analytical approach will be needed if we are to build on initial success and unrealized potential to improve quality and patient safety.
The term “EBM” was introduced by a group of clinician researchers and educators at McMaster University during the early 1990s. It was initially defined as “a systemic approach to analyzed published research as the basis of clinical decision making.” Subsequently, as the EBM movement matured as a discipline, the early proponents and developers provided a more complete definition: “Evidence based medicine is the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients. The practice of evidence-based medicine means integrating individual clinical expertise with the best available external clinical evidence from systematic research (1).”
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Figure 2. EBM queries can be constructed using the PICO method. This table was borrowed from the Centre for Evidence-Based Medicine web site: www.cebm.net.
Of course, the concept of practicing medicine based on the scientific method has been around for years. The days of bloodletting with leeches are behind us, but rigorous scientific evaluation of medicine reached critical mass only in the last century. The first double-blind randomized controlled trial (RCT) was conducted in 1931; the study tested the use of sanocrysin for treatment of tuberculosis (2). Since then, there has been an exponential growth in clinical trials. This information explosion requires new approaches to integrating the ever-increasing knowledge with patient care; the concurrent revolution in information technology provides opportunities limited only by our own imaginations.
EBM is not without its critics: “It is cookbook medicine,” “It focuses on cost efficiency,” “I can’t find an RCT that fits my patient,” and “It doesn’t take into account the clinician’s experience” are often argued points. If EBM is not used effectively, all the criticisms are appropriate. Sacket, one of the earliest proponents and likely EBM’s most eloquent champion, refuted the claim that EBM is “cookbook medicine.” He argued that EBM requires a bottom-up approach that integrates the best external evidence with individual clinical expertise and patients’ choice. External clinical evidence informs, but does not replace, individual clinical expertise. The physician must decide whether the external evidence applies to the individual patient at all and, if so, how it should be integrated into a clinical decision (1).
Neither is EBM strictly about RCTs and meta-analysis. It’s about tracking down the best available evidence for your question and, thus, your patient. Sometimes a cohort study is best when you want to find the prognosis of a certain illness. Similarly, a cross-sectional study may be most appropriate when you’re trying to determine the sensitivity and specificity of a test. If a disease once thought universally fatal is proven otherwise in a case report, then a randomized control trial is hardly necessary. Finally, an RCT or meta-analysis is not always going to be available for the disease process you are dealing with, but EBM gives us the skill set to look down the evidence pyramid and find the next best thing (Figure 1).