PEPs - Clinical Quality and Evidence

Module 2 - Evidence

Evidence-based medicine

“The practice of evidence-based medicine means integrating individual clinical expertise with the best available external clinical evidence from systematic research.” ¹

Clinical information comes from two principal sources, the individual patient and research. To provide effective care both types of information are needed. Evidence-Based Medicine (EBM) is the method by which we gain the current best evidence taken from scientific and clinical research in order to make decisions about the care of patients.  EBM aims to apply the best available evidence gained from the scientific method to clinical decision making.

EBM helps you to:

Ask the right questions

As a clinician you’ll need to be able to narrow down all the information in a clinical scenario to the questions that are most appropriate for your individual patient, such as: “Will this particular treatment benefit my patient?” or “What side effects might be expected in my patient?”

Look for evidence

You’ll also need to be able to look in the right places for the best available evidence that addresses those specific questions about particular patients. There is a vast amount of evidence out there – of varying degrees of quality. The medical information used by doctors should always come from the medical or scientific literature, where rigorous methods have been used for collecting and analysing the data which are then presented in an unambiguous, interpretable style. However, getting valid information from published research can be confusing and time-consuming, if you don’t know the best way to approach it.

Interpret the evidence

Even information published in a medical journal could be biased or incorrect. The problem is that “many papers published in medical journals have potentially serious methodological flaws.” ²  A major focus of EBM is to assess the strength of evidence of the risks and benefits of treatments (including lack of treatment) and diagnostic tests. The ability to make these judgements is called critical appraisal (an assessment based on careful analytical evaluation).

Critical appraisal of evidence is not as difficult as it sounds, and there are online checklists to help you (e.g., Centre for Evidence Based Medicine - University of Oxford). If you are not a research academic, the purpose of this will often be to assess what is the best management for the patient in front of you: individual evidence-based decision making. This is not a process you do alone, but in partnership with the patient.

This can be structured using “The Six ‘A’s” ³

1) Acquire enough information to understand the patient’s concern.

2) Ask a clinically relevant question.

3) Access information to answer the question.

4) Assess the quality of information.

5) Apply the information to the clinical question

6) Assist the patient to make a decision

So, overall, EBM is about trying to improve the quality of the information on which decisions are made. It is relevant to all aspects of Medicine, and it’s a skill that you will (or should) use throughout your career.

Have a look at this short video introducing the importance of an evidence-based approach to health care, in an amusing and informative way.

In EBM in Years 1 & 2, you were introduced to fundamental skills such as searching the literature for high quality evidence and critically appraising such evidence. How confident are you at these skills? You can refresh your memory by looking back at the Year 1 & 2 EBM content inside Blackboard.

Also, the University of Manchester library provides some online tutorials on how to find and appraise evidence – they are very helpful.

Take some time to view the tutorials titled:

  • Planning your literature search.
  • Getting started with health science databases.
  • Exploring the health science databases.
  • OVID online
  • Critical appraisals

You can improve your skills further by attending library courses on search strategies, reference managers and on dealing with information overload. You can book these via the MyLearning Essentials training calendar in your online library resources.

The BMJ also provides an online module/test that covers these key concepts.

  1. Sackett, D. (1996) Evidence based medicine: what it is and what it isn't, BMJ, 312, 71-72
  2. Greenhalgh, T. (1997) How to read a paper: getting your bearings (deciding what the paper is about), BMJ, 315, 243-246
  3. Meza JP, Passerman DS. (2011) Integrating Narrative Medicine and Evidence-based Medicine: The Everyday Social Practice of Healing. London: Radcliffe Publishing