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PHARM 3823 Health & Biostats Evidence-Based Medicine PICO. Frederic Murray Assistant Professor MLIS, University of British Columbia BA, Political Science, University of Iowa Instructional Services Librarian Al Harris Library frederic.murray@swosu.edu. Today’s Class.
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PHARM 3823Health & BiostatsEvidence-Based MedicinePICO Frederic Murray Assistant Professor MLIS, University of British Columbia BA, Political Science, University of Iowa Instructional Services Librarian Al Harris Library frederic.murray@swosu.edu
Today’s Class • Learn about EBM and how to formulate a good clinical question using PICO • How to research PICO questions • Understand the hierarchy of resources available to Pharmacy Students
Databases & Search Engines • A large, regularly updated file of digitized information related to a specific subject or field. • Computer software designed to help the user locate information available at sites on the World Wide Web by selecting categories from a hierarchical directory of subjects (example: Yahoo!) or by entering appropriate keywords or phrases (Google).
Databases • Using Keywords • Thesaurus • Using Limiters • Narrow or Specify your search
Evidence Based Medicine • Evidence-based medicine (EBM) is using and carrying out practices based on the best available knowledge. Clinical Expertise EBM Best Research Patient Preferences
Why Evidence Based Medicine? • Exponential Growth in Medical Literature • Impossible for Medical Practitioners to keep up • http://tinyurl.com/d9dvuz5
Why Evidence Based Medicine? • There are 7827 articles relevant to family practice published every month • That’s 260 articles a day (every day) to keep up….
Why Evidence Based Medicine? • There are a lot of Evidence Based Review Sources that Synthesize and critically appraise healthcare literature • They can be found in Your Library • Also….you’ll be needing this again in Pharm 4302 Drug Information
RCT- Gold Standard • Randomized controlled trials are the most rigorous way of determining whether a cause-effect relation exists between treatment and outcome • Random allocation to intervention groups • Patients and trialists should remain unaware of which treatment was given until the study is completed-although such double blind studies are not always feasible or appropriate • All intervention groups are treated identically except for the experimental treatment
Yale University School of Medicine Filtered Information Appraises the quality of studies and often make recommendations for practice UnfilteredEvidence is not always available via filtered resources. Searching the primary literature may be required
Step 1: Formulating a well-built question • Step 2: Identifying articles and other evidence-based resources that answer the question • Step 3: Critically appraising the evidence to assess its validity • Step 4: Applying the evidence • Step 5: Re-evaluating the application of evidence and areas for improvement
The fundamental skill necessary to conduct evidence-based medicine is learning to design a Well-Built Clinical Question.
Step 1: Well Built Question • With clinical cases, there is often a barrage of details to digest. • To effectively search EBM resources, you need to decide what details are important.
Step 1: Well Built Question • what about the Population? • what about the Intervention? • what about the Comparison? • what about the Outcome? PICO P The patient’s disorder or disease I The intervention or finding under review C A comparison intervention (if applicable) O The outcome
Pico: Example • “In a 55-year-old man with a 35-year-old history of chronic smoking, would the administration of bupropion as compared to a nicotine replacement therapy (NRT) be a better therapy in causing long-term abstinence from smoking?
PICO Example • “In a 55-year-old man with a 35-year-old history of chronic smoking, would the administration of bupropion as compared to a nicotine replacement therapy (NRT) be a better therapy in causing long-term abstinence from smoking?
PICO: A State of Mind • A systematic way to identify important concepts in a case • Formulate a question for searching • Often you will often not have a comparison intervention
Framing Good Questions • Describe the subject • How would I describe a group of patients similar to this one?” • Define which intervention • x-ray versus an MRI • Define the type of outcome • changes in a physical sign • outcome of a diagnostic test • response to therapy
PICO: Case 1# • A nine-year-old girl presents in the ER with diffuse abdominal pain and loss of appetite. You suspect appendicitis, and need to decide which imaging modality is best for making the diagnosis—CT or ultrasound.
PICO: Case 2# A middle aged obese Japanese man comes to your clinic for his annual physical exam. He brings in a bottle of Chitosan, an OTC dietary supplement. He has family history of cardiovascular disease and colon cancer. He wants to lose weight to reduce his risk. His daily diet is high in carbohydrates including rice and noodles.
PICO: Case 1# P Child with suspected appendicitis I CT C Ultrasound O Reliable diagnosis of appendicitis Is ultrasound or CT better for diagnosing appendicitis in a child?
PICO: Case 2# P Middle aged obese Japanese male I Chitosan C No treatment (placebo) O Weight loss In a middle aged, obese Japanese male, what is the safety and efficacy of Chitsosan vs. no treatment for weight loss?
Step 2: Database/Resource Searching These resources generally fall into two categories • Filtered resources • Unfiltered resources
MeSH : Build a Broader Lexicon: • MeSH is the National Library of Medicine's controlled vocabulary thesaurus • Search MeSH to find new entry terms i.e. ultrasound: echography echotomography ultrasonography
Filtered Resources • Used to decide on a course of action for a patient (diagnosis, treatment, etc.) • Clinical experts pose a question and then synthesize "evidence" to state conclusions based on the available research. • The literature has been searched and results evaluated to provide an answer to a clinical question
Filtered Resources • National Guideline Clearinghouse • Cochrane Database of Systematic Reviews (CDSR) • Annual Reviews Online
Unfiltered Resources • Search the unfiltered resources to see if any new research has been done • Unfiltered resources provide the most recent information…but • Not designed for answering clinical questions • Evaluation takes time, effort and expertise
Unfiltered Resources • Medline • Medline PubMed • CINAHL • OVID
Research Exercise Is ultrasound or CT better for diagnosing appendicitis in a child? P Child with suspected appendicitis I CT C Ultrasound O Reliable diagnosis of appendicitis
Research Exercise:Search Appendicitis Database: National Guideline Clearinghouse Keyword: appendicitis Age of Target Population: Adolescent Guideline Category: Evaluation Sex of Target Population: Female
National Guideline Clearinghouse Clinical policy: critical issues in the evaluation and management of emergency department patients with suspected appendicitis. 2000 (revised 2010 Jan). NGC:007643American College of Emergency Physicians - Medical Specialty Society.
Research Exercise:Search Appendicitis Database: Cochrane Database of Systematic Reviews Keyword: appendicitis Limiter: Full Text Limiter: Protocol
Cochrane Database of Systematic Reviews • Wild, J. (2013). Ultrasonography for diagnosis of acute appendicitis. Cochrane Database Of Systematic Reviews, (2), doi:10.1002/14651858.CD010402 • Rud, B. (2012). Diagnostic accuracy of Computed Tomography for Appendicitis in Adults. Cochrane Database Of Systematic Reviews, (7), doi:10.1002/14651858.CD009977
Step 3: Critical Appraisal • If the study is from a primary source (one that provides original data on a topic with no commentary) • Do a “validity” (closeness-to-truth) check Dachs, R., Darby-Stewart, A., & Graber, M. (2012). Antibiotics for acute otitis media in young children: the case of the shifting end points. American Family Physician, 85(2), 104.
Step 3: Critical Appraisal • Diagnosis • Therapy • Harm • Prognosis
Step 3: Critical Appraisal Diagnosis Was the assignment of patients to treatment groups randomized? Were all enrolled patients accounted for at the conclusion of the study? Were the treatment groups similar at the start of the study? Therapy • Did patient sample include appropriate spectrum of patients to those found in general practice? • Was the gold standard applied to all cases?
Step 3: Critical Appraisal Harm Prognosis Was the patient sample representative? Was the length of the follow-up adequate? Was the follow-up complete? • Were exposures and outcomes measured similarly? • Was the follow-up adequate?
III. Class Exercise: Therapy Questions Dachs, R., Darby-Stewart, A., & Graber, M. (2012). Antibiotics for acute otitis media in young children: the case of the shifting end points. American Family Physician, 85(2), 104. • Was the assignment of patients to treatment groups randomized? • Were all enrolled patients accounted for at the conclusion of the study? • Were the treatment groups similar at the start of the study?
Step 4: Applying the Evidence • Decide how the study and/or other information applies to your question • Diagnosis • Therapy • Harm • Prognosis
Step 4: Applying the Evidence Diagnosis Therapy According to the study results how much would my patient benefit from the treatment? • Is the test available, accurate and affordable? • Can I estimate the pretest probability of the disease in question?
Step 4: Applying the Evidence Harm Prognosis How will the evidence influence my choice of treatment? • Can the study results be applied to my patient? • Are there alternative therapies? • What is my patient’s risk for adverse effects?
Step 5: Re-evaluating the Evidence • Was the diagnosis and treatment successful? • Is there new information/data in the literature? • How can I improve and/or update my clinical decisions? HOW TO MANAGE ALL THIS INFORMATION?
V. Class Exercise Worksheet 2# • Develop PICO Questions for the case studies • Search filtered/unfiltered database to answer your question (1 source) • List Citation (APA)
Questions? • Contact me: • Frederic Murray • 774-7113 • frederic.murray@swosu.edu