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Topic 7 How to read medical journal articles. Worked examples. Jarmila Potomková Medical Librarian Jiri Gallo Department of Orthopaedic Surgery Palacky University Faculty of Medicine Olomouc, Czech Republic Updated February 2009 potomkov@tunw.upol.cz.
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Topic 7How to read medical journal articles. Worked examples. Jarmila Potomková Medical Librarian Jiri Gallo Department of Orthopaedic Surgery Palacky University Faculty of Medicine Olomouc, Czech Republic Updated February 2009 potomkov@tunw.upol.cz
CASP – Critical Appraisal Skills Programme: Appraisal Tools http://www.phru.nhs.uk/Pages/PHD/CASP.htm
Professional Databases with Critically Appraised Topics Clinical Evidence http://www.clinicalevidence.com (fee) • Systematic reviews • Question(s) • Option(s) • Grades of evidence • Beneficial • Likely beneficial • Trade off between benefit and harm • Unknown effectiveness • Unlikely beneficial • Etc.
Searching –Finding - Reading Clinical Question for Today: Osteoarthritis of the knee : Treatment with corticosteroids
Adapted from:Evidence-Based Practice Workbook2 ed. by P. Glasziou et al., BMJ Books, 2007 • Objectives: To determine the efficacy of intra—articular corticosteroid injections for osteoarthritis in the knee.
Background QuestionWhat is osteoarthritis? Sources: • Merck Manual of Diagnosis and Therapy • Merck Manual – Home Edition. • Available from: http://www.merckmanual.com
osteoarthritis +knee +corticosteroids
PubMed Search ConsolidationSearch Strategy • Selection of search terms • Keywords • Phrases • Synonyms • Combination of search terms • Boolean logic • Application of limits • Occurrence of search terms • Title, Title/Abstract, All fields • Types of articles • Age groups • Etc.
Boolean logic • AND: Combines terms to limit your search as both concepts must be present in all retrieved articles • Example: osteoarthritis AND knee* • OR: Widens your search as either term can be present in all retrieved articles • Example: osteoarthritis OR arthritis • NOT: Limits your search by excluding a concept as one term must be present and the second term must not be present • Example: osteoarthritis NOThip
Truncation * • PubMed finds all terms that begin with a given text string • Example • osteoarthriti* • PubMed retrieves: osteoarthritis, osteoarthritic,,,,,,,,
Osteoarthritis of the knee : treatment with corticosteroids Search terms: osteoarthriti*; arthriti* knee* corticosteroid*; glucocorticoid*; steroid*
Search Strategy Suggestions Step 1 (osteoarthriti* OR arthriti*) AND knee* Limits: Title Step 2 corticosteroid* OR steroid* OR glucocorticoid* Limits: Title Step 3 Combine searches #1 AND#2 Step 4 Limits: Type of articles: Meta-analysis
Systematic Reviews & Meta-Analysis Statistical methods Statistical methods
PubMed Search Results • All: 57 • Reviews: 8 • Meta-analysis: 4 • Including Cochrane reviews
HOMEWORK Basic Steps of Critical Appraisal of Systematic Reviews/Meta-analyses
What question did the study ask? • P/Patient, population, problem • I/Intervention • C/Comparison • O/Outcome
How well was the study done? Rapid Critical Appraisal of a Systematic Review CHECKLIST
Does the systematic review address a focused question? (PICO) The main question being addressed should be clearly stated. • The intervention, such as therapy ordiagnostic test, and the outcomes will often be expressed in terms of a simple relationship.
Where do I find the information? • Title, Abstract or final paragraph of the Introduction should clearly state the question. • If you still cannot ascertain what the focused question is after reading these sections, search for another paper.
Is the question used to direct the search and select articles for inclusion? • The inclusion or exclusion of studies in a systematic review should be clearlydefined a priori. • The eligibility criteria used should specify the patients, interventions and outcomes. • In many cases the type of study design will also be a key component of the eligibility criteria.
Where do I find information? • The Methods section should describe in detail the inclusion and exclusion criteria. • Normally, this will include the study design.