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Christopher Eccleston. Centre for Pain Research The University of Bath c.eccleston@bath.ac.uk. Order of service. Cochrane Collaboration Methods Communication Methods Development Other. Cochrane Collaboration. Founded in 1993 Iain Chalmers Following Archie Cochrane
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Christopher Eccleston Centre for Pain Research The University of Bath c.eccleston@bath.ac.uk
Order of service • Cochrane Collaboration • Methods • Communication • Methods Development • Other
Cochrane Collaboration • Founded in 1993 Iain Chalmers • Following Archie Cochrane • Principles of Evidence for all • 52 CRGs • Centres & Fields • Volunteer • Consumerist • Quality • Control over Bias • Living Library
Cochrane Collaboration Review GroupPain, Palliative & Supportive CarePaPaS • http://papas.cochrane.org • Established in 1998 • Based in Oxford • Updates 2 years • Cochrane Database Systematic Reviews • The Cochrane Library • Field Editors
Current Status • Editorial Board • Mike Bennett • Andrew Moore • Tim Steiner • Amanda Williams • Acute Pain Vacancy • Title to Protocol to review • 120 reviews • 70 protocols and titles • 2 overviews • IASP SIG Systematic Reviews • ACTINPAIN Writing Group
Methods • Guidance? • Common Methods • RevMan (free) • Supported (Title Reg) • Professional Searching • Published Protocols • International (not English) • Meta-analysis • Bias Control • Communication www.cochrane-handbook.org/
Features • Standard description of condition/intervention • Full description of studies (Tables) • Assessment of heterogeneity • Clinical pooling like with unlike • Statistical (small n) • Sub-group analyses • (dose)
Meta-analysis + • Effect sizes • Forest plots • Assumptions • Fixed effects • Assume variation is sampling error • Violations • Heterogeneity • Small n • Junk in Junk out • Quality of primary
Communication • Abstracting • Plain Language Summary • Risk of Bias Tool • Summary of Findings • Podcast • Journal Club • PICO
Summary of Findings Guyatt GH, Oxman AD, Vist GE, Kunz R, Falck-Ytter Y, Alonso-Coello P, Schünemann HJ; GRADE Working Group. GRADE: an emerging consensus on rating quality of evidence and strength of recommendations. BMJ. 2008 Apr 26;336(7650):924-6.
The GRADE system classifies the quality of evidence in one of four grades:
Methods 1: Outcomes • Use outcomes (IMMPACT) chronic • Pain reduction: 30% moderate, 50% Good • Other • Time to re-medication • non-pain outcomes • Not recommended • Odds ratios • Analgesic consumption • No use of group means • Pain relief has a U shaped distribution • Response analysis on dichotomous data • Adverse events
Use of quality rating scales? Jadad scale Non-pharmacological interventions? Methods 2: ROB
Methods 4: NNT • Inverse of the absolute risk • Benefits • Easier to understand • Compare between treatments easily • Costs • More is worse • Can hide effect (EMEA Report) • Never an NNT alone • RR, NNT, NNH, percentage improvement
Stabilizing a review • Publication bias • Stabilizing (not updating)
Overclaiming No effective or no evidence of effect Quality control in non-pharmacological trials Language of confidence Simplify vs simplistic (95% read abstract) 30 or 50 or 70 Responder analysis vs response analysis Does pain relief drive QoL outcomes? Comparing treatments Overview reviews Stopping rules, Switch rules Indirect comparisons Judgement biases Behavioural economics (choices) Myth of rational man Not discussed
Communication • What is the risk doctor? • Tell it to me straight. • What are my chances doctor? • Tell it to me straight.