The document provides guidance on using evidence-based medicine (EBM) to effectively answer clinical queries. It differentiates between background and foreground questions and introduces the PICO method for refining questions to determine the appropriate study type for various clinical scenarios. Additionally, it outlines resources for finding answers and emphasizes the importance of comparing the quality of evidence when researching clinical questions.

1. Using EBM to Answer Clinical Queries Robin Featherstone Clinical Medicine Librarian [email_address] http://www.slideshare.net/featherr

2. Agenda Background vs. Foreground questions Clinical evidence Study types Searching exercises Using PICO to refine questions Searching down the levels of evidence Questions

3. EBM REFRESHER

4. Two Broad Question Categories Background = basic information about a subject What is strabismus? What is a screening test for strabismus? Foreground = specific to a clinical scenario Is Botulinum Toxin (Botox) more effective than surgery to improve cosmetic appearance for a patient with advanced strabismus?

6. Sources for Background Questions Resource Example Textbook Robbins basic pathology Handbook Adolescent medicine: a handbook for primary care Manual The Washington manual of surgery Encyclopaedia Encyclopedia of respiratory medicine Dictionaries Dorland’s pocket medical dictionary

7. Refine Foreground Questions using PICO P = Patient or Problem I = Intervention or Exposure C = Comparison O = Outcomes

8. Determine your Question Type 1,2 Aetiology: What is the cause of the disease and its mode of operation? Diagnosis: How accurate is this diagnostic test? Prognosis: What is the probable course of the disease? Therapy: Is one intervention more effective than another? Prevention: How to reduce the risk of this disease? Cost-effectiveness: Is one intervention more cost-effective than another? Quality of life: What will be the patient’s quality of life? 1 Heneghan, Carl, and Douglas Badenoch. Evidence-Based Medicine Toolkit. 2nd ed. Malden, Mass.: BMJ Books/Blackwell Pub., 2006. 2 Glover, Jan, and Lei Wang. Find it Fast: The Clinical Question : www.med.yale.edu/library/education/guides/screencasts/finditfast/finditfast_2/

9. Studies to Answer Each Type 1,2 1 Heneghan, Carl, and Douglas Badenoch. Evidence-Based Medicine Toolkit. 2nd ed. Malden, Mass.: BMJ Books/Blackwell Pub., 2006. 2 Glover, Jan, and Lei Wang. Find it Fast: The Clinical Question : www.med.yale.edu/library/education/guides/screencasts/finditfast/finditfast_2/ Type of Question Type of Evidence Aetiology Randomized controlled trials Case-control or cohort studies Case series Diagnosis Diagnostic validation studies Prospective studies / blind comparison to a gold standard Prognosis Inception cohort studies Case control studies Case series Therapy Randomized controlled trials Systematic reviews / meta-analyses Prevention Randomizes controlled trials Cohort studies, case control studies Systematic reviews / meta-analyses Cost-effectiveness Economic analyses Quality of life Qualitative studies

10. Level of Evidence Pyramid Qualitative Studies

11. CASE STUDIES AND SEARCHING EXERCISES

12. Case study 1 Refine this case into a question and identify the best study type to answer that question. Your patient travels regularly on business and suffers frequently from the effects of jet lag. They’ve tried tomato juice and exercise but neither seems to help. They ask if there is anything else they can do?

13. Create an answerable question What are the most clinically effective preventative measures for reducing the symptoms of jet lag? P atient, Problem, or Population Jet lag I ntervention C omparison O utcome(s) Reduced symptoms

14. Identify your question type 1 Heneghan, Carl, and Douglas Badenoch. Evidence-Based Medicine Toolkit. 2nd ed. Malden, Mass.: BMJ Books/Blackwell Pub., 2006. 2 Glover, Jan, and Lei Wang. Find it Fast: The Clinical Question : www.med.yale.edu/library/education/guides/screencasts/finditfast/finditfast_2/ Type of Question Type of Evidence Aetiology Randomized controlled trials Case-control or cohort studies Case series Diagnosis Diagnostic validation studies Prospective studies / blind comparison to a gold standard Prognosis Inception cohort studies Case control studies Case series Therapy Randomized controlled trials Systematic reviews / meta-analyses Prevention Randomizes controlled trials Cohort studies, case control studies Systematic reviews / meta-analyses Cost-effectiveness Economic analyses Quality of life Qualitative studies

15. Select a resource Qualitative Studies

16. Exercise Select one of the following resources to answer the question: What are the most effective preventative measures for jet lag? Cochrane Library ACP’s PIER PubMed Google Scholar

17. Conclusions Number of results Source Hits Cochrane Library 2 ACP’s PIER 43 PubMed 561 (56 if using MeSH with prevention subheading) Google Scholar About 78,300

18. Discussion How does the quality of these results compare? Which resource would you use in a clinical setting? In a research setting?

19. Case Study 2 A patient with breast cancer asks how women typically feel after mastectomy. How will her life differ after surgery? What step should we take first to answer this question?

20. Create an answerable question What is the quality of life of patients following mastectomy? P atient, Problem, or Population Patients following mastectomy I ntervention C omparison O utcome(s) Quality of life

21. Identify your question type 1 Heneghan, Carl, and Douglas Badenoch. Evidence-Based Medicine Toolkit. 2nd ed. Malden, Mass.: BMJ Books/Blackwell Pub., 2006. 2 Glover, Jan, and Lei Wang. Find it Fast: The Clinical Question : www.med.yale.edu/library/education/guides/screencasts/finditfast/finditfast_2/ Type of Question Type of Evidence Aetiology Randomized controlled trials Case-control or cohort studies Case series Diagnosis Diagnostic validation studies Prospective studies blind comparison to a gold standard Prognosis Inception cohort studies Case control studies Case series Therapy Randomized controlled trials Systematic reviews / meta-analyses Prevention Randomizes controlled trials Cohort studies, case control studies Systematic reviews / meta-analyses Cost-effectiveness Economic analyses Quality of life Qualitative studies

22. Select a resource Qualitative Studies

23. Exercise Search the following resources to answer the question: What is the quality of life of patients following mastectomy? PsycINFO CINAHL Google Scholar

24. Conclusions Number of results Source Hits PsycINFO 10 CINAHL 92 Google Scholar about 21,900

25. Discussion How do qualitative questions compare to other question types? How do you assess the quality of these results?

26. Case Study 3 A patient expresses concern before cataract surgery about the amount of pain they will experience. You consider administering intracameral anaesthetic (lidocaine) as a supplement to topical anaesthetic, but you’re not sure if the additional anaesthesia will reduce intraoperative pain perception compared with topical anaesthetic alone.

27. Create an answerable question P atient, Problem, or Population I ntervention C omparison O utcome(s)

28. Create an answerable question In cataract surgery patients, does topical anaesthetic alone reduce pain perception when compared to topical anaesthetic supplemented by intracameral lidocaine? P atient, Problem, or Population Patients undergoing cataract surgery I ntervention Topic anaesthesia alone C omparison Topical anaesthesia with intracameral lidocaine O utcome(s) Reduction of pain perception

29. What kind of question is this?

30. 1 Heneghan, Carl, and Douglas Badenoch. Evidence-Based Medicine Toolkit. 2nd ed. Malden, Mass.: BMJ Books/Blackwell Pub., 2006. 2 Glover, Jan, and Lei Wang. Find it Fast: The Clinical Question : www.med.yale.edu/library/education/guides/screencasts/finditfast/finditfast_2/ Type of Question Type of Evidence Aetiology Randomized controlled trials Case-control or cohort studies Case series Diagnosis Diagnostic validation studies Prospective studies blind comparison to a gold standard Prognosis Inception cohort studies Case control studies Case series Therapy Randomized controlled trials Systematic reviews / meta-analyses Prevention Randomizes controlled trials Cohort studies, case control studies Systematic reviews / meta-analyses Cost-effectiveness Economic analyses Quality of life Qualitative studies

31. Select a resource

32. Exercise Search whatever resource you think would best answer the question: In cataract surgery patients, does topical anaesthetic alone reduce pain perception when compared to topical anaesthetic supplemented by intracameral lidocaine?

33. Results What resources did you search? Did you find the answer to your question?

34. Summary Background vs. Foreground questions Using PICO to formulate an answerable question Identifying question types Identifying studies that best answer your question Searching down the levels of evidence

35. QUESTIONS?