PHARM 3823 Health & Biostats Evidence-Based Medicine or Please Pass the PICO… Frederic Murray Assistant Professor MLIS, University of British Columbia BA, Political Science, University of Iowa Instructional Services Librarian Al Harris Library [email protected] Peer Reviewed Evidence Based Medicine • Evidence-based medicine (EBM) is using and carrying out practices based on the best available knowledge. EBM Clinical Expertise Best Research Patient Preferences Why Evidence Based Medicine? • Exponential Growth in Medical Literature • Impossible for Medical Practitioners to keep up Why Evidence Based Medicine? • There are 7827 articles relevant to family practice published every month • That’s 17 articles a day (every day) to keep up…20 hours a day reading. 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 Yale University School of Medicine Filtered Information Appraises the quality of studies and often make recommendations for practice Unfiltered Evidence is not always available via filtered resources. Searching the primary literature may be required Evidence-Based Medicine Five fundamental steps • 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 what what what about about about about the the the the Population? Intervention? Comparison? 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-yearold 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 Example 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 I Class Exercise: Worksheet 1a# • 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. I Class Exercise: Worksheet 1a# P I C O Child with suspected appendicitis CT Ultrasound Reliable diagnosis of appendicitis Is ultrasound or CT better for diagnosing appendicitis in a child? Step 2: Database/Resource Searching These resources generally fall into three categories • General information (background) resources • Filtered resources • Unfiltered resources. Build a Broader Lexicon: (MeSH) Worksheet 1b# • Use MeSH to discover new terms • Search MeSH to find new entry terms for ultrasound… (in class we’re only concerned with the C in PICO…[for now]) MeSH is the National Library of Medicine's controlled vocabulary thesaurus General Resources • Stedman's Online Medical Dictionary – Database • Current Diagnosis and Treatment – Ebrary • Drug information handbook –Lexi-Comp – 2nd floor Library 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 • Annual Reviews Online • Cochrane Database of Systematic Reviews (CDSR) • National Guideline Clearinghouse National Guideline Clearinghouse • Hypertension – Age of Target Population – Guideline Category – Intended Users 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 Search Example II. Class Exercise: Search Otitis Media • Cochrane Database of Systematic Reviews (CDSR) Filtered • MedLine Plus Unfiltered • Stedman's Online Medical Dictionary General 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 Therapy Diagnosis • Was the assignment of • Did patient sample patients to treatment include appropriate groups randomized? spectrum of patients to those found in general • Were all enrolled patients practice? accounted for at the conclusion of the study? • Was the gold standard applied to all cases? • Were the treatment groups similar at the start of the study? Step 3: Critical Appraisal Harm • Were exposures and outcomes measured similarly? • Was the follow-up adequate? Prognosis • Was the patient sample representative? • Was the length of the follow-up adequate? • Was the follow-up complete? 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 Therapy Diagnosis • According to the study • Is the test available, results how much would accurate and affordable? my patient benefit from • Can I estimate the the treatment? pretest probability of the disease in question? Step 4: Applying the Evidence Harm • Can the study results be applied to my patient? • Are there alternative therapies? • What is my patient’s risk for adverse effects? Prognosis • How will the evidence influence my choice of treatment? 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? IV. Class Exercise Worksheet 1c# – Research the PICO Question: Is ultrasound or CT better for diagnosing appendicitis in a child? – Select two filtered & one unfiltered database – Record your findings ( hint: use the abstracts) 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 • [email protected] Thanks!