Why Evidence Based Medicine May Be Bad for You and Your Patients

Abstract

Evidence based medicine (EBM) has inveigled itself into almost every aspect of medical practice in the last decade (or more) with promises of better delivery of health care and a more rational basis by which to deliver that care. Thus, an appropriate question at this time might be: How does the evidence for the so-called “evidence” of EBM stack up? This review argues that the basis of EBM is so deeply flawed that in many cases it cannot usefully inform clinical practice, reflected in fact by the current majority outcome of most trials as “no-blood,” or no result. The illusion that knowledge can be created using only empiric data from large randomised controlled trials (RCTs) that test single hypotheses and draw conclusions from multi-variate regression correlations is examined. Particular attention is paid to how this idea undermines the advancement of in-depth, fact-based medical knowledge and, as a result, patient care. The flawed logic behind the EBM rationale of treating risk, as determined by probabilistic outcome measurements, means EBM will never be equipped to identify individual benefit or harm. Thus, it can never usefully inform the attending clinician about titrating therapy to the individual case. Hence, the results of EBM can never improve a single patient’s care, only the averaged odds faced by that patient being treated by a statistical outcome correlation based therapeutic choice, at best. Finally, despite its emphasis on large trials utilising inherently flawed logic, EBM is ruling the “mindshare” of medical and administrative thinking, precluding other lines of thought and stifling scientific debate. Clinicians need to re-think how they gather, interpret and act on evidence. and, in fact, what defines “evidence” outside the definition of trial size, randomisation and blinding. Through its implicit emphasis on treating risk, and not disease, EBM paradoxically risks much more. The monotonous march of performing large RCTs, crunching the statistics and presenting the results for the latest journal issue, has come to define medical research. As a result, it has stifled the idea that reasoned evidence, based on the complementary use of both hypothesis-based trials and logic-based reasoning has any contribution to make in this brave new world. Forgetting of course that it was just such complementary forms of research engagement that drove the last several hundred, if not thousand, years of scientific and medical research – until now. So, enter, if you will, this editorial on the state of the evidence, or lack thereof, in medical research today. The authors claim no competing interests outside the biases that they entered the room with.