Evidence Based Medicine Dr. Mansour AlZahrani SB-FM,ABFM,MRCGP[INT] Assistant professor of Family Medicine Head of Family Medicine Department

Definition Evidence-based medicine requires the integration of the best research evidence with our clinical expertise and our patient’s unique values and circumstances. Patient Values Clinical Expertise Best research evidence EBM Straus SE, Richardson WS, Glasziou P, Haynes RB. Evidence-based medicine: how to practice and teach EBM 3d ed. London: Churchill Livingstone, 2005

S TEPS IN E VIDENCE B ASED R ESEARCH 1.Asking answerable questions 2.Finding the best evidence 3.Critically appraising the evidence 4.Applying a decision 5.Evaluation Heneghan C, Badenoch D. Evidence-based medicine toolkit. 2d ed. Malden, MA: Blackwell, 2007

The Answerable Question

S TEP 1 Asking answerable questions – focused, searchable, clinical PICO Patient, Problem, Population (subjects) Intervention or therapy – may include coalition- building and/or collaborative programs (study groups) Comparison, Control, Context (study groups) Outcome (results)

Asking the Precise Question Background questions Basic aspect of a disease Pathophysiology Etiology Basic treatment Who, what, when, how Foreground questions Specific knowledge Have 4 parts: Patient/problem Intervention Comparison intervention Clinical outcomes

Background or Foreground? Is prednisone helpful in asthma? What are the newest medication for asthma? Does ventolin used acutely make you feel better? What is asthma?

Background or Foreground? What is asthma? (B) What are the newest medication for asthma? (B) Does atrovent used acutely make you feel better? (F) Is prednisone helpful in asthma? (F or B) Foreground if compare to other drugs Background if interested in how it works

Can You Identify PICO? In children under 6 months, how does sleeping on back compared to sleeping on the stomach in terms of risk of SIDS? In children under 6 months (P), how does sleeping on back (I) compared to sleeping on the stomach (C) in terms of risk of SIDS (O)?

Can You Form a PICO Question? Clinical scenario: 5 yo with moderate persistent asthma now in severe acute asthma exacerbation. Intern gave 2x ventolin and pulmicort with good improvement. Intern asks how good is pulmicort for prevent hospitalization?

S TEP 2 Finding the best evidence with which to answer the question through structured searches and understanding the literature Primary Studies Clinical trials Randomized Controlled Trials Multicenter studies Secondary (synthesized, summarized) Studies Reviews Meta-analyses

MEDLINE The world’s largest biomedical database Over 5,000 journals indexed, with worldwide coverage Covers all aspects of biosciences and healthcare Database of 16+ million journal citations, 1950 to the present 90% are in English ; 79% have abstracts The primary component of PubMed

So What Is PubMed? PubMed is a tool to search: MEDLINE (1950 to present) Produced by NCBI National Center for Biotechnology Information, part of NLM Accessible worldwide on the Web at no charge

Accessing PubMed Directly at: Or, National Library of Medicine’s homepage:

PubMed Screen Layout Feature Tabs Query Box aka Search Box Blue Sidebar

Searching PubMed Let’s use this search: What’s the evidence for the use of beta blockers to prevent atrial fibrillation after bypass surgery

Enter Your Search in Query Box

Results Screen

The Details Tab Details Tab tells you how PubMed has translated your search

When to Limit? There are many reasons for refining a search strategy. You may want to: Exclude foreign language titles Look for articles published within a certain timeframe Retrieve articles that focus on specific populations Look only at clinical research studies

The Limits Tab

Other Ways To Limit Your Search Add additional terms to query box Use Boolean Connectors AND, OR, NOT stress AND depression depression OR sadness OR unhappy depression NOT manic

Working with Results The Display bar is used with the following pull-down menus: Summary lets you select other formats, such as Abstract, Brief or Citation format Show and Sort By offer additional display options Send to lets you print, save, , order documents or the Clipboard (a temporary holding bin)

What Are Those Icons?

This PubMed feature allows you to: Save search strategies and set-up automatic updates Save bibliographies Select filters that customize and sort your search results and more…

Saved Searches My NCBI box lets you Sign in or for first time users, Register. After a search is run, click on the Save Search link to save the search strategy.

Saved Searches After you sign in, the Save Search box displays. 1) Enter a name for your search (something meaningful), 2) click Yes or No for automatic updates and 3) click OK after you have made your selections.

More tutorial please see

STUDIES, STUDIES, STUDIES

STUDIES Research Design Case Studies/Reports Community TrialCross Sectional Research Cohort Case-Control Correlational Observational Qualitative Study Interview Experimental Descriptive Randomized Clinical Trial Non-Randomized Clinical Trial Analytical Cambron JA. Study Design. Lombard: National University of Health Sciences; 2008.

Good questions are the backbone of practicing EBM. It takes practice to ask the well-formulated question.

The nature of the question asked is critically experience dependent. GENERAL KNOWLEDGE SPECIFIC KNOWLEDGE TYPE OF QUESTION CLINICAL EXPERIENCE

L EVELS OF E VIDENCE Kramer BS. Weighing scientific evidence. Washington DC: National Academies Press; 2009

S TEP 3 Critically appraising the evidence for its validity (closeness to the truth), impact (size of the effect) and applicability (usefulness in clinical practice) Is it valid? Is it important? Can it help?

S TEP 4 Applying a decision - Combining findings to make a recommendation, placing the evidence into context, incorporating recommendation into a specific patient situation, clinical setting or organization How much will it help a patient or population? Does it meet their values and goals? Is it cost-effective?

S TEP 5 Evaluation - Determining and measuring the effectiveness of the practice change over time How could it be done better next time? What is the outcome of using (or not using) particular information and its impact on clinical practice?