Evidence Based Practice 101

  •   August 14, 2014
  •  Leanne Loranger, PT, Practice Advisor

What is evidence based practice (EBP)? The reality is that there are many answers to this question. David Sackett has long been credited as the grandfather of Evidence Based Medicine (EBM). He and his co-authors defined EBM as the “conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients/clients” (cited by Law and MacDermid)1. I was in the midst of my first year of practice when that definition was published and when I read that definition for the first time, my heart sank. To me it meant that only research evidence mattered, and since it is hard to create a double-blinded randomized controlled trial of a physiotherapy intervention, I believed EBP was impossible.

However, years later I discovered Law’s (2004) comment: “…EBP can be considered to be a combination of information from what we know from research, what we have learned from clinical wisdom and what we learned from information from the client and their family. This combination of information enables us to work together with clients and families to make the best use of knowledge.”1 What a relief! Suddenly the clinical experience that I had spent years accumulating meant something and had a place in the triad of evidence. The reality is that evidence based practice means combining research evidence with the knowledge of clinicians and the patient’s experience and preferences to formulate a client-centered approach to care.

The research foundation of how and why a physiotherapy intervention works is exactly that: a foundation, upon which the other relevant information is constructed into a plan of care. Making sure that this foundation is solid is of critical importance. As pointed out in the Sicily statement “health care delivered in ignorance of available research evidence, misses important opportunities to benefit patients and may cause significant harm.”2

Greenhalgh provides a number of examples where the failure to implement evidence into practice and the reliance on ‘expert’ opinion has led to unnecessary suffering and death3. Woolf and Johnson demonstrated that “in many cases, we would add more value by increasing our efforts to implement this evidence than by doing more research to develop a different drug”4 (or other treatment.) Expert opinion can, in the words of Mulrow, be “criticized as haphazard and biased, subject to the idiosyncratic impressions” of the expert.5 “In extreme cases, an ‘expert opinion’ may consist simply of the lifelong bad habits… of an ageing clinician.”3 In short, evidence and evidence based practice matter when it comes to improving patient outcomes and separating respected health-care professionals from ‘snake-oil salesmen’.

As Greenhalgh states, “Evidence-based medicine is about coping with change, not about knowing all the answers before you start. In other words, it is not so much about what you have read in the past but about how you go about identifying and meeting your ongoing learning needs and applying your knowledge appropriately.”3 The critical part of the statement is not in knowing the answers, but in knowing the relevant questions for your area of practice and knowing how to find the answers to those questions. It also means making linkages to those who conduct clinical research in order to help formulate research questions that matter for clinicians and for patients.

Does EBP matter to you? How do you apply EBP to your practice? Share your comments via email to lloranger@physiotherapyalberta.ca or on twitter @PTAlberta.

Related Reading
Trisha Greenhalgh

  • “How to Read a Paper: The Basics of Evidence-based Medicine”
  • Various British Medical Journal publications

Physiotherapy Alberta is introducing a new series of articles to our newsletter aimed at helping members read and appraise research literature. In a recent survey, members identified the need for support to assist them to sort through the piles of research published each week and to identify ‘good evidence’ that applies to practice. Through Research in Focus articles and the Evidence Corner we aim to provide high quality evidence to inform practice, but what if you need to answer a research question on your own? Do you know how to formulate an effective research question? Do you remember how to determine if the research is of high quality?

The focus of the evidence based practice article series is to address questions, and to create a dialogue between Physiotherapy Alberta and members on the subjects of evidence based practice and knowledge translation. Our intent is not to be the expert lecturer on the topic, but rather to be a knowledgeable voice in the conversation.


  1. Law M, MacDermid J. Introduction to evidence-based practice. Evidence-based rehabilitation: A guide to practice. Thorofare: SLACK Incorporated. 2008.
  2. Dawes M, Summerskill W, Glasziou P, Cartabellotta A, Martin J, Hopayian K, Porzsolt F, Burls A, Osborne J. Sicily Statement on evidence-based practice. BMC Medical Education 2005; 5(1): 1-7. Available from: http://www.biomedcentral.com/content/pdf/1472-6920-5-1.pdf
  3. Greenhalgh T. Why read papers at all? How to read a paper: The basics of evidence-based medicine. Hoboken: Wiley-Blackwell BMJ Books, 2010.
  4. Woolf SH, Johnson RE. The break-even point: When medical advances are less important than improving the fidelity with which they are delivered. Annals of Family Medicine 2005; 3(6): 545-552
  5. Mulrow CD. Systematic Reviews: Rationale for systematic reviews. BMJ 1994; 309: 597