Literature Searching for Clinical Effectiveness Ben Skinner

Systematic review: the relationship between clinical experience and quality of health care Choudhry NK, et al. Annals of Internal Medicine 2005;142:260–273.

Evidence Based Medicine? Class 0:Things I believe Class 0a:Things I believe despite the available data Class 1:Randomized, controlled clinical trials (RCTs) that agree with what I believe Class 2:Other prospectively collected data Class 3:Expert opinion Class 4:RCTs that don't agree with what I believe Class 5:What you believe that I don't

The majority of bold statements expressed during grand rounds lack scientific merit 25 cases of bold statements were identified Examples of statements identified as exotic include: Crohn’s disease always exacerbates during pregnancy Alpha blockers are useful in treating acute urinary retention in women Legionella pneumonia never causes pleuritic pain. After review of the literature, only 8 (32%) statements were found to be supported by scientific evidence. In 17 (68%) cases, the available literature actually contradicted the statement or no literature was available (P<0.05). Linthorst GE, et al. Medical Education 2007;41:

Trials of aprotinin for prevention of surgical bleeding

Cumulative meta- analysis of trials of aprotinin for prevention of surgical bleeding

Peer Review The Centre for Evidence-Based Medicine regularly read, appraise and digest clinical research published in c150 peer-reviewed medical journals They find that: Approximately 5% are methodologically valid and reliable Of those 5%, approximately 5% are clinically relevant As a rule of thumb, 0.25% of peer-reviewed research is worth your time

Individual Clinical Expertise Best External Evidence Patients’ Values & Expectations Clinical Effectiveness

NHS Library Services Searches done for you on demand Over 1500 full-text electronic journals plus hundreds of electronic books including the Oxford Handbooks KnowledgeShare Personalised current awareness Further advice and support

Bare essentials for clinical effectiveness (Basic) Understanding of Well structured clinical question Appraised / Non-appraised resources Hierarchy of evidence Critical appraisal

Appraised vs Non-appraised resources Tertiary evidence Clinical guidelines, Systematic Reviews Secondary evidence Critically appraised digests of primary research Primary evidence Original studies or trials

Clinical questions Patient / Population: Which patients or populations are we interested in? Are there any subgroups that need to be considered? Intervention / Indicator: Which intervention, treatment or approach should be used? Comparison: What is/are the main alternative/s to compare with the intervention? Outcome: What are the important outcomes for the patient?

Your patient is an 11-year-old girl with childhood myoclonic epilepsy. Standard care in your department is to prescribe ACTH (adrenocorticotrophin hormone) and you wonder what the evidence is for its use

Patient:11-year-old (?), Child, childhood, paediatric, pediatric, female(?), Childhood myoclonic epilepsy, juvenile myoclonic epilepsy, epilepsy, epileptic, seizure Intervention:ACTH, adrenocorticotrophin hormone, corticosteroids, steroids Comparison:Placebo, usual care Outcomes:Frequency of seizure, adverse events, infection, weight gain, hypertension, etc

Enter as many terms into a search box as you wish - It retrieves the documents in which all the terms occur Search for a phrase by using quotes E.g. “prenatal diagnosis” You can use brackets and logical operators E.g. (prenatal OR antenatal) AND screening You can truncate words with the * symbol E.g. infertil* would find infertile or infertility Basic search techniques

Guidelines and Pathways National Library for Health Guidelines: National Guideline Clearinghouse: Map of Medicine: OMNI:

National Library for Health Guidelines Finder

National Guidelines Clearinghouse

Map of Medicine Username and Password are both: C-Sussex

Clinical guidelines Be critical Well structured questions Transparent methodology Multidisciplinary groups Evidence and recommendation grading Open peer review process Easy to navigate

Cochrane Library for systematic reviews > Click on “Cochrane Library” A set of databases that contains reliable evidence about the effectiveness of interventions: Treatment Diagnosis and screening Health promotion Organisation of care Some groups better than others Be critical Check date of last update Check scope of review

Cochrane Database of Systematic Reviews Full text of systematic reviews published by the Cochrane Collaboration Each review is updated at least every two years Database of Abstracts of Reviews of Effects (DARE) Critically appraised summaries of non-Cochrane systematic reviews Cochrane Central Register of Controlled Trials (CENTRAL) Bibliographic references to randomised controlled trials Not critically appraised NHS Economic Evaluation Database (NHSEED) Critically appraised summaries of economic evaluations of interventions The Cochrane Library contains…

Cochrane Library > Cochrane Library

Pre-appraised resources Evidence-Based Medicine - Produced by the Centre for Evidence-Based Medicine Searches over 100 journals Finds the 5% of trials that are methodologically sound and presents only those that are clinically important

Pre-appraised resources Bandolier Identifies a handful of studies that answer a question, and reports on their quality More of a primary care focus – unusual questions posed by clinicians Light-hearted tone - easy to read and digest

Pre-appraised resources Clinical Knowledge Summaries : Gathers good quality evidence on healthcare interventions Includes patient information, background information, drug information, etc Presents a digested summary of the evidence Use DynaMed for clinical questions in secondary care

Searching across multiple resources National Library for Health: Turning Research into Practice (TRIP): Google:

National Library for Health (Primarily evidence-based resources)

Google Google should be one of the last places you look because the ratio of useful to non- useful resources is so tiny To make a Google search more effective add site:nhs.uk to your search, e.g. Google Scholar restricts to academic resources but it is better to use medical databases epilepsy lorazepam site:nhs.uk

Primary research databases Medline is accessible in two ways: Pubmed: Use “Clinical Queries” to narrow down results Links to full text are misleading – not always free! National Library for Health: Requires an ATHENS password Direct access to full text articles where available NOTE: NLH also gives access to Embase (only 35% overlap with Medline)

Remember… Evidence-based medicine is not about finding a study that looks like it might be useful… … it is about making sure you haven’t missed another study that might be better. If you do go to the primary literature you should initially choose articles based on study design

Hierarchy of evidence (for studies of therapy) Systematic Reviews Randomised Control Trials Cohort Studies Case-Control Studies Cross Sectional Surveys Case StudiesSTRONG WEAK

Critical appraisal Not just title, author and journal dependant. Need the skills to evaluate what you read Different criteria for all types of research (for guidelines) Training available from the Library Services

Clinical scenario An 84-year-old woman was admitted due to increasing shortness of breath on exertion that was accompanied by paroxysmal nocturnal dyspnoea and irregular pulse. Based on her symptoms, signs and the ECG investigation that was performed, she was diagnosed with atrial fibrillation. Since patients with AF are at high risk of embolic stroke, they are usually treated with an anticoagulant or anti-platelet agents. You want to find out the effectiveness of each of these treatments in reducing the risk of embolic stroke