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

3. 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

4. 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

5. 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
Clinical
Expertise
Best research
evidence
EBM
Sackett DL, Rosenberg WMC, Gray JAM, Haynes RB, Richardson WS: Evidence based medicine: what it is and what it isn’t. BMJ 1996;312:71-2.
This definition of what EBM is and isn’t has gained wide acceptance and made it easier for us to get our points across.

7. WHY Evidence Based Medicine (EBM)?
Best for Patients
Protect Doctors (medico-legal cases)
Judgement and expert opinion should be based on EBM

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

9. 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

10. 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

11. 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.

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

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

16. 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.

17. 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.

18. 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."

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

20. 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:

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

22. 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

23. 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.

24. 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?

25. 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

26. 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?

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

30. PRACTICE

41. 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 ( 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: 
Search for Primary Sources e.g.  PubMED

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

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

45. وزارت بهداشت، درمان و آموزش پزشكي http://www.behdasht.gov.ir
وزارت بهداشت، درمان و آموزش پزشكي

46. Secondary sources e.g. RCOG guidelines
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 , CATmaker is a computer-assisted critical appraisal tool

47. 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
Internal validity : Basically, how much can we trust the results based on what the investigators did.

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

49. Interested to learn more ?
Centre for Evidence Based Medicine

51. Masters Programme

53. 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

54. 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

55. Coping with the overload: three possible things you might try
PRESENTATION ONE
Coping with the overload: three possible things you might try
27/08/2018
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
Introduction to Evidence-Based Practice

56. 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

57. Thank You