Evidence Based Medicine Dr Reza Nasr MD MRCOG

Evidence Based Medicine Dr. Reza Nasr MD MRCOG DFFP Consultant in Obstetrics and Gynaecology University of London

Definition • Conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients • "the use of mathematical estimates of the risk of benefit and harm, derived from high-quality research on population samples, to inform clinical decision-making in the diagnosis, investigation or management of individual patients

• The practice of evidence based medicine can be divided into the following components : • Identifying a problem or area of uncertainty Asking a relevant, focused, clinically important question that is answerable Selecting the most likely resources to search Searching, and appraising the evidence found Assessing the clinical importance of the evidence Assessing the clinical applicability of the evidence Acting on and appropriately applying the evidence Assessing the outcomes of your actions Authoring-summarizing and storing records for future reference

What is evidence-based medicine? “Evidence-based medicine is the integration of best research evidence with clinical expertise and patient values” Sackett DL Patient Concerns EBM Best research Clinical Expertise evidence

WHY Evidence Based Medicine (EBM)? • Best for Patients • Protect Doctors (medico-legal cases)

What Pushes Us … ? Toward Away • • • Risk of patient harm Want to do better Avoid litigation Curiosity Prove colleagues wrong • Anxiety • Internet informed patient • • • Time We already know the answer Fatigue Access Inferiority complex-anxietyafraid of admitting knowledge gaps Laziness Lack of support Previous failure at searching Lack of resources No one else does it Fear of change

• The need for EBM • Medical research is continually discovering improved treatment methods and therapies • Research findings are often delayed in being implemented into clinical practice • Clinicians must stay current with changing therapies • Evidence-based practice has been shown to keep clinicians up to date

The Five Steps of Evidence Based Practice 1. Asking Focused Questions: translation of uncertainty to an answerable question 2. Finding the Evidence: systematic retrieval of best evidence available 3. Critical Appraisal: testing evidence for validity, clinical relevance, and applicability 4. Making a Decision: application of results in practice 5. Evaluating Performance: auditing evidence-based decisions

• • • Step 1: ASKING focused clinical questions that arise in caring for patients. Step 2: ACQUIRING the best available evidence through electronic searching. Step 3: APPRAISING the quality of the evidence acquired against explicit methodological criteria. Step 4: APPLYING the evidence appropriately to the clinical management of individuals. Step 5: ASSESSING performance in relation to the previous four steps.

EBM practice requires: 5 A’s • Asking • Acquiring • Appraising • Applying • Assessing

1. Asking Focused Questions: translation of uncertainty to an answerable question • Anatomy of a well articulated question 1. 2. 3. 4. the patient or problem being addressed the intervention or exposure being considered the comparison intervention or exposure, when relevant the clinical outcomes of interest

The Patient • Start with the patient: a clinical problem/ question arises out of the care of the patient. The Question • Construct a well-built question derived from the case.

• Pauline is a new patient who recently moved to the area to be closer to her son and his family. She is 67 years old and has a history of congestive heart failure brought on by several myocardial infarctions. • She has been hospitalized twice within the last 6 months for worsening of heart failure. At the present time she remains in normal sinus rhythm. She is extremely diligent about taking her medications (enalapril, aspirin and simvastatin) and wants desperately to stay out of the hospital. She lives alone with several cats. • You think she should also be taking digoxin but you are not certain if this will help keep her out of the hospital. You decide to research this question before her next visit.

• The next step in this process is to take the identified problem and construct a question that is relevant to the case and is phrased in such a way as to facilitate finding an answer. This is called "constructing a well built clinical question". •

• For our patient, the clinical question might be : • In elderly patients with congestive heart failure, is digoxin effective in reducing the need for rehospitalization ?

• Type of question • Two additional elements of the well-built clinical question are the type of question and the type of study. This information can be helpful in focusing the question and determining the most appropriate type of evidence. • The most common types of questions related to clinical tasks are:

Diagnosis how to select and interpret diagnostic tests Therapy how to select treatments to offer patients that do more good than harm and that are worth the efforts and costs of using them Prognosis how to estimate the patient's likely clinical course over time and anticipate likely complications of disease Harm/Etiolo how to identify causes for disease gy (including iatrogenic forms (

• For our patient, the clinical question is : • In elderly patients with congestive heart failure, is digoxin effective in reducing the need for rehospitalization ? • It is a therapy question and the best evidence would be a randomized controlled trial (RCT). If we found numerous RCTs, then we might want to look for a systematic review

Anatomy of a good clinical question • 1 - Patient or problem • How would you describe a group of patients similar to yours? What are the most important characteristics of the patient? This may include the primary problem, disease, or co-existing conditions. Sometimes the sex, age or race of a patient might be relevant to the diagnosis or treatment of a disease.

• 2 - Intervention, prognostic factor, or exposure • Which main intervention, prognostic factor, or exposure are you considering? What do you want to do for the patient? Prescribe a drug? Order a test? Order surgery? What factor may influence the prognosis of the patient? Age? Co-existing problems? What was the patient exposed to? Asbestos? Cigarette smoke?

• 3 - Comparison • What is the main alternative to compare with the intervention? Are you trying to decide between two drugs, a drug and no medication or placebo, or two diagnostic tests? Your clinical question does not always need a specific comparison

• 4 - Outcomes • What can you hope to accomplish, measure, improve or affect? What are you trying to do for the patient? Relieve or eliminate the symptoms? Reduce the number of adverse events? Improve function or test scores ?

Patient / Problem congestive heart failure, elderly Intervention digoxin Comparison, if any none, placebo Outcome primary: reduce need for hospitalization; secondary: reduce mortality

• PRACTICE

2. Finding the Evidence: systematic retrieval of best evidence available Look for secondary sources: • • • Guidelines: UK National Library for Health, NICE, SIGN; US National Guidelines Clearinghouse; Canadian Medical Association; New Zealand Guidelines Group. Royal college of Obstetricians and Gynaecologists (www. rcog. org. uk), ACOG, ﻭﺯﺍﺭﺕ ﺑﻬﺪﺍﺷﺖ CATs: CAT Crawler Evidence-Based Summaries: Bandolier, Clinical Evidence Structured Abstracts: EBM Online, ACP Journal Club Systematic Reviews: Cochrane Library To search several of the databases simultaneously you can use: www. tripdatabase. com Search for Primary Sources e. g. Pub. MED

Royal College of Obstetricians and Gynaecologists www. rcog. org. uk

www. nice. org. uk National Institute for Clinical Excellence

www. thecohcranelibrary. com

3. Critical Appraisal: testing evidence for validity, clinical relevance, and applicability • Secondary sources e. g. RCOG guidelines – Appraisal has been performed with level of evidence clearly written next to each statement • Primary sources e. g. Pubmed – Appraisal kits available on www. cebm. net , CATmaker is a computer-assisted critical appraisal tool

4. Making a Decision: application of results in practice • Internal validity refers to the extent a study properly measures what it is meant to. • External validity refers to the extent to which we can generalize the results of a trial to the population of interest

5. Evaluating Performance: auditing evidence-based decisions • Auditing your process and/or results

Interested to learn more ? • http: //www. cebm. net/ • Centre for Evidence Based Medicine

Masters Programme

Common mistakes in teaching EBM • Teaching EBM fails: – When learning how to do research is emphasised over how to use it – When learning how to do statistics is emphasised over how to interpret them – When teaching EBM is limited to finding flaws in published research

Common mistakes in teaching EBM • Teaching EBM fails: – When it humiliates learners for not already knowing the ‘right’ fact or answer – When it bullies learners to decide to act based on fear of others’ authority or power, rather than on authoritative evidence and rational argument – When the amount of teaching exceeds the available time or the learner’s attention

Coping with the overload: three possible things you might try A. Read guidelines & evidence-based abstraction journal (and cancel other journals) B. Keep a logbook of your own clinical questions C. Run a case-discussion journal club with your practice

Take home messages • EBM should be the language of medicine • EBM should be taught in medical schools and hospitals • EMB should be taught to patients! • Look for the answerable questions in secondary sources first (UK RCOG, NICE, ACOG, SOGC, RCOG for AUS and NZ • Challenge colleagues by asking for evidence • Explain to patients the evidences for treatments and investigations

Thank You