Critical Thinking A tour through the science of neuroscience
|
|
- Ruth Walker
- 5 years ago
- Views:
Transcription
1 Critical Thinking A tour through the science of neuroscience NEBM 10032/5 Publication Bias Emily S Sena Centre for Clinical Brain Sciences, University of Edinburgh slides
2 Bias Biases in research and reporting are presumably exacerbated by systems of publication and career evaluation that reward impact and productivity over quality and ability to replicate studies Systematic reviews Can only include data made available If unpublished data are systematically different to the published literature then the summarised data, opinions and understanding will be biased.
3 Growing Research Area Increased efforts in the study of conscious and unconscious biases in research Threaten human health Waste economic resources Threaten scientific progress Fanelli and Ioannidis, 2013
4 Reporting bias Neutral and negative studies Publication bias Time lag bias Language bias Vibration effects Selective analysis reporting Selective outcome reporting
5 Publication Bias Neutral and negative studies remain unpublished less likely to be identified in systematic review leads to the overstatement of efficacy in meta-analysis Hot topic for clinical trials summary results of clinical trials conducted in Europe publicly available
6 How to assess for it? Effect size and corresponding standard error To assess for its presence Funnel plot Egger regression Estimate efficacy in the absence of publication bias Trim and Fill
7 Funnel Plots Work on the basis that small studies are likely to be more spread around the mean Small studies that are significant are more likely to be published inverted funnel Funnel plots are visually assessed and most useful with a large number of studies Relative measures plotted on a log scale ensures that effects of the same magnitude but opposite directions are equidistant from 1.0 Used to examine whether smaller studies report larger treatment effects
8 Funnel Plot Precision Effect Size
9 Egger Regression Egger regression statistically assess asymmetry of the funnel plot The standardised effect is regressed on the precision A weighted regression of the effect size on it standard error with the weight equal to the precision With no asymmetry the regression line and its 95% CI will pass through the origin Again, not proof of bias but does raise the questions regarding the interepration of results
10 Egger Regression Precision Effect Size/Standard Error
11 Trim and Fill Missing studies are iteratively identified ( trimming ) and are replaced ( filling ) in order to calculate an adjusted estimate of effect size Studies with the largest deviation from the mean are trimmed The remaining symmetrical plot is used to recalculate the summary effect Trimmed studies are replaced and their counterparts filled to correct variance The mirror axis is placed along the adjusted estimate
12 Trim and Fill Overall efficacy was reduced from; 32% (95% CI 30 to 34%) to 26% (95% CI 24 to 28%)
13 Publication bias in experimental stroke Trim and Fill suggested 16% of experiments remain unpublished Best estimate of magnitude of problem Overstatement of efficacy 31% Only 2% publications reported no significant treatment effects
14 Cancer Induced Bone Pain - animals 103 filled studies 2.79 ( ; n=257) to 1.6 ( ; n=360) 42.3% relative overstatement
15 Publication bias 20% - 32% n expts Estimated unpublished Reported efficacy Corrected efficacy Stroke infarct volume % 27.5% EAE - neurobehaviour % 15.0% EAE inflammation % 37.5% EAE demyelination % 30.5% EAE axon loss % 41.7% AD Water Maze sd sd AD plaque burden sd sd
16 Few Studies 16 Studies OR 6.7 ( )
17 Few Studies 7 filled trials OR 6.7 to % relative overstatement in effect?
18 More Data 165 comparisons OR 1.8 ( )
19 More Data 34 filled trials OR 1.8 to % relative overstatement in effect
20 Limitations Too few studies, ideally want >25 Need reasonable dispersion of sample size For sparse data the Mantel-Haenszel methods are probably more appropriate for weighting but Trim and Fill function only has the inverse variance method enabled Small study effects may have other causes ORs rather than NNT Measure of variance difficult to derive for NNT OR are more extreme compared to RR if the event rate is high so asymmetry may observed with OR
21 Note of caution. Funnel plot asymmetry has a number of potential sources Selection bias (Publication bias, reporting bias, biased inclusion criteria) True heterogeneity (study effect differs according to study size, differences in underlying risk) Data irregularities (poor methodological design, inadequate analysis, fraud) Artefact (poor choice of effect measure) Chance
22 Is the effect an artefact of bias? We checked for its presence and impact but not whether the overall effect is robust Rosenthal s fail-safe N How many studies do we need to nullify the observed effect? Statistical rather than substantiative Assumes missing studies have an effect of zero rather than negative or small positive effects Orwin s Fail-safe N Attempts to address both issues
23 Other options Cumulative meta-analysis by size This allows you to see whether adding smaller studies shifts a stable effect size of larger studies Smaller studies are generally given less weight but are they influencing the pooled estimate Used a fixed model (Mantel-Haenszel) where less weight is given to smaller studies. Will not be thrown by few aberrant studies
24 Cumulative MA by size
25 Cumulative MA by size
26 Other options - Excess Significance To identify whether there is an excess of significant studies within previously conducted systematic reviews of neurological disorders
27 Excess Significance Test Examines whether too many individual studies in a meta-analysis report statistically significant results Driven by selective reporting of analyses or outcomes Low power to detect bias in a single meta-analysis with few studies but is applicable across many metaanalyses in a field
28 Methods Dataset 6 diseases Alzheimer s disease, EAE, focal ischaemia, intracerebral haemorrhage, Parkinson s disease, and spinal cord injury 60 meta-analyses 4,445 experiments Median sample size = 16 (IQR 11-20)
29 Methods Data extraction Year of publication Intervention Effect size + standard error Sample size Quality score items Peer review, randomisation, allocation concealment, blinded assessment of outcome, sample size calculation, conflict of interest Funnel plot asymmetry
30 Methods Excess Significance Test [(O)>(E)] Observed nominally positive studies p<0.05 Binomial test Expected positive studies is power True effect size Fixed effect size of the most precise study Wilcoxon rank sum test
31 Assessed excess significance In aggregate across the six disease Within each disease Subgroup Amount of heterogeneity Significant summary fixed effect Egger Regression Reporting of measures to minimise bias (quality score)
32 Expected significant results = 919 (21%) Observed significant results = 1719 (39%) Excess significance was present across all six neurological disorders in all subgroups defined by methodological or reporting characteristics The strongest excess significance was observed in meta-analyses where small study effects were also observed with the least precise studies
33 Some research areas may be more susceptible to bias Softer sciences Proportion of studies reporting positive results increases moving from physical sciences to medical to social sciences. Research choices are more influenced by a scientist s own beliefs, expectations and wishes. Behavioural studies Regional Publish or perish long characterised US-based research Research from Asian and developing countries tends to be rejected unless they report extraordinary results Fanelli and Ioannidis, 2013
34 Further analysis of research bias 82 meta-analyses 1,174 primary outcomes Samples from health related biological and behavioural research Measured how individual results deviated from the overall summary estimate of effect from within their respective meta-analysis Stratified by research type and country of origin Fanelli and Ioannidis, 2013
35
36 Hypotheses In the life sciences there are perverse incentives (publication, funding, promotion) to produce positive results with little attention paid to their validity Leads to a body of evidence with an inflated proportion of published studies with statistically significant results This potentially compromises the utility of animal models and contributes to translational failure
37 What happens Small (underpowered), poorly conducted studies reach spurious (falsely positive) conclusions but are published because they are seen to be interesting. Small (perhaps) poorly conducted (sometimes) studies not reaching the same conclusions are not published. Investigators become conditioned by the apparent success that comes from conducting small underpowered studies Investigators keep trying to replicate the positive studies Exacerbated by the combination of pressures to publish and winner-takes-all system of rewards.
38 What can we do? Problem: Not all outcomes are reported A priori analyses not always reported What we need: We need to know if scientists report what they set out to report Solution: Published Protocols Registries
39 Thanks to... Edinburgh Malcolm Macleod Kieren Egan Hanna Vesterinen Gill Currie Rustam Al-Shahi Salman Joseph Frantzis Project Students Melbourne David Howells Ana Antonic Peter Batchelor Taryn Wills Sarah McCann Stanford/Ioannina John Ioannidis Kostad Tsilidis Orestis Panagiotou Eleni Aretouli Vangelis Evangelou Utrecht Bart van der Worp Nottingham Philip Bath Translators NHS R&D methodology program Chief Scientist Office e_drugs_they_prescribe.html
Choice of axis, tests for funnel plot asymmetry, and methods to adjust for publication bias
Technical appendix Choice of axis, tests for funnel plot asymmetry, and methods to adjust for publication bias Choice of axis in funnel plots Funnel plots were first used in educational research and psychology,
More informationComparison of Different Methods of Detecting Publication Bias
Shaping the Future of Drug Development Comparison of Different Methods of Detecting Publication Bias PhUSE 2017, Edinburgh Janhavi Kale, Cytel Anwaya Nirpharake, Cytel Outline Systematic review and Meta-analysis
More informationC2 Training: August 2010
C2 Training: August 2010 Introduction to meta-analysis The Campbell Collaboration www.campbellcollaboration.org Pooled effect sizes Average across studies Calculated using inverse variance weights Studies
More informationMeta Analysis. David R Urbach MD MSc Outcomes Research Course December 4, 2014
Meta Analysis David R Urbach MD MSc Outcomes Research Course December 4, 2014 Overview Definitions Identifying studies Appraising studies Quantitative synthesis Presentation of results Examining heterogeneity
More informationEvaluation of Excess Significance Bias in Animal Studies of Neurological Diseases
Evaluation of Excess Significance Bias in Animal Studies of Neurological Diseases Konstantinos K. Tsilidis 1., Orestis A. Panagiotou 1., Emily S. Sena 2,3, Eleni Aretouli 4,5, Evangelos Evangelou 1, David
More informationLive WebEx meeting agenda
10:00am 10:30am Using OpenMeta[Analyst] to extract quantitative data from published literature Live WebEx meeting agenda August 25, 10:00am-12:00pm ET 10:30am 11:20am Lecture (this will be recorded) 11:20am
More informationEstimation statistics should replace significance testing
Estimation statistics should replace significance testing Adam Claridge-Chang 1, 2, 5 and Pryseley N. Assam 3, 4 1. Program in Neuroscience and Behavioral Disorders, Duke-NUS Medical School, Singapore
More informationMeta-Analysis. Zifei Liu. Biological and Agricultural Engineering
Meta-Analysis Zifei Liu What is a meta-analysis; why perform a metaanalysis? How a meta-analysis work some basic concepts and principles Steps of Meta-analysis Cautions on meta-analysis 2 What is Meta-analysis
More informationProblem solving therapy
Introduction People with severe mental illnesses such as schizophrenia may show impairments in problem-solving ability. Remediation interventions such as problem solving skills training can help people
More informationFixed Effect Combining
Meta-Analysis Workshop (part 2) Michael LaValley December 12 th 2014 Villanova University Fixed Effect Combining Each study i provides an effect size estimate d i of the population value For the inverse
More informationResults. NeuRA Treatments for internalised stigma December 2017
Introduction Internalised stigma occurs within an individual, such that a person s attitude may reinforce a negative self-perception of mental disorders, resulting in reduced sense of selfworth, anticipation
More informationRandomized experiments vs. Propensity scores matching: a Meta-analysis.
Randomized experiments vs. Propensity scores matching: a Meta-analysis. Antonio Olmos Priyalatha Govindasamy Research Methods and Statistics University of Denver American Evaluation Association Conference
More informationGLOSSARY OF GENERAL TERMS
GLOSSARY OF GENERAL TERMS Absolute risk reduction Absolute risk reduction (ARR) is the difference between the event rate in the control group (CER) and the event rate in the treated group (EER). ARR =
More informationThresholds for statistical and clinical significance in systematic reviews with meta-analytic methods
Jakobsen et al. BMC Medical Research Methodology 2014, 14:120 CORRESPONDENCE Open Access Thresholds for statistical and clinical significance in systematic reviews with meta-analytic methods Janus Christian
More informationTypes of Data. Systematic Reviews: Data Synthesis Professor Jodie Dodd 4/12/2014. Acknowledgements: Emily Bain Australasian Cochrane Centre
Early Nutrition Workshop, December 2014 Systematic Reviews: Data Synthesis Professor Jodie Dodd 1 Types of Data Acknowledgements: Emily Bain Australasian Cochrane Centre 2 1 What are dichotomous outcomes?
More informationResults. NeuRA Mindfulness and acceptance therapies August 2018
Introduction involve intentional and non-judgmental focus of one's attention on emotions, thoughts and sensations that are occurring in the present moment. The aim is to open awareness to present experiences,
More informationMethod. NeuRA Biofeedback May 2016
Introduction is a technique in which information about the person s body is fed back to the person so that they may be trained to alter the body s conditions. Physical therapists use biofeedback to help
More informationModels for potentially biased evidence in meta-analysis using empirically based priors
Models for potentially biased evidence in meta-analysis using empirically based priors Nicky Welton Thanks to: Tony Ades, John Carlin, Doug Altman, Jonathan Sterne, Ross Harris RSS Avon Local Group Meeting,
More informationThe translational roadblock, characterized by beneficial
Special Report Methodological Quality of Experimental Stroke Studies Published in the Stroke Journal Time Trends and Effect of the Basic Science Checklist Jens Minnerup, MD*; Verena Zentsch, MD*; Antje
More informationPerformance of the Trim and Fill Method in Adjusting for the Publication Bias in Meta-Analysis of Continuous Data
American Journal of Applied Sciences 9 (9): 1512-1517, 2012 ISSN 1546-9239 2012 Science Publication Performance of the Trim and Fill Method in Adjusting for the Publication Bias in Meta-Analysis of Continuous
More information18/11/2013. An Introduction to Meta-analysis. In this session: What is meta-analysis? Some Background Clinical Trials. What questions are addressed?
In this session: What is meta-analysis? An Introduction to Meta-analysis Geoff Der Unit Statistician MRC/CSO Social and Public Health Sciences Unit, University of Glasgow When is it appropriate to use?
More informationMeta-analysis: Advanced methods using the STATA software
Page 1 sur 5 Wednesday 20 September 2017 - Introduction to meta-analysis Introduction I. Why do a meta-analysis? II. How does a meta-analysis work? Some concepts III. Definition of an «effect size» 1.
More informationSystematic Reviews and Meta- Analysis in Kidney Transplantation
Systematic Reviews and Meta- Analysis in Kidney Transplantation Greg Knoll MD MSc Associate Professor of Medicine Medical Director, Kidney Transplantation University of Ottawa and The Ottawa Hospital KRESCENT
More informationSystematic Reviews. Simon Gates 8 March 2007
Systematic Reviews Simon Gates 8 March 2007 Contents Reviewing of research Why we need reviews Traditional narrative reviews Systematic reviews Components of systematic reviews Conclusions Key reference
More informationTraumatic brain injury
Introduction It is well established that traumatic brain injury increases the risk for a wide range of neuropsychiatric disturbances, however there is little consensus on whether it is a risk factor for
More informationAnimal-assisted therapy
Introduction Animal-assisted interventions use trained animals to help improve physical, mental and social functions in people with schizophrenia. It is a goal-directed intervention in which an animal
More informationEPSE 594: Meta-Analysis: Quantitative Research Synthesis
EPSE 594: Meta-Analysis: Quantitative Research Synthesis Ed Kroc University of British Columbia ed.kroc@ubc.ca March 14, 2019 Ed Kroc (UBC) EPSE 594 March 14, 2019 1 / 39 Last Time Synthesizing multiple
More informationNeuRA Sleep disturbance April 2016
Introduction People with schizophrenia may show disturbances in the amount, or the quality of sleep they generally receive. Typically sleep follows a characteristic pattern of four stages, where stage
More informationThe comparison or control group may be allocated a placebo intervention, an alternative real intervention or no intervention at all.
1. RANDOMISED CONTROLLED TRIALS (Treatment studies) (Relevant JAMA User s Guides, Numbers IIA & B: references (3,4) Introduction: The most valid study design for assessing the effectiveness (both the benefits
More informationDistraction techniques
Introduction are a form of coping skills enhancement, taught during cognitive behavioural therapy. These techniques are used to distract and draw attention away from the auditory symptoms of schizophrenia,
More informationMore than 3Rs Improving the validity and reproducibility of animal research
CAWS Symposium 2017 Purdue University, West Lafayette, IN May 18th, 2017 More than 3Rs Improving the validity and reproducibility of animal research Hanno Würbel Division of Animal Welfare Vetsuisse Faculty,
More informationEvaluating the results of a Systematic Review/Meta- Analysis
Open Access Publication Evaluating the results of a Systematic Review/Meta- Analysis by Michael Turlik, DPM 1 The Foot and Ankle Online Journal 2 (7): 5 This is the second of two articles discussing the
More informationResults. NeuRA Hypnosis June 2016
Introduction may be experienced as an altered state of consciousness or as a state of relaxation. There is no agreed framework for administering hypnosis, but the procedure often involves induction (such
More informationResults. NeuRA Worldwide incidence April 2016
Introduction The incidence of schizophrenia refers to how many new cases there are per population in a specified time period. It is different from prevalence, which refers to how many existing cases there
More informationEvidence-Based Medicine and Publication Bias Desmond Thompson Merck & Co.
Evidence-Based Medicine and Publication Bias Desmond Thompson Merck & Co. Meta-Analysis Defined A meta-analysis is: the statistical combination of two or more separate studies In other words: overview,
More informationOverview. Goals of Interpretation. Methodology. Reasons to Read and Evaluate
Overview Critical Literature Evaluation and Biostatistics Ahl Ashley N. Lewis, PharmD, BCPS Clinical Specialist, Drug Information UNC Hospitals Background Review of basic statistics Statistical tests Clinical
More informationLearning objectives. Examining the reliability of published research findings
Examining the reliability of published research findings Roger Chou, MD Associate Professor of Medicine Department of Medicine and Department of Medical Informatics and Clinical Epidemiology Scientific
More informationCritical Appraisal Series
Definition for therapeutic study Terms Definitions Study design section Observational descriptive studies Observational analytical studies Experimental studies Pragmatic trial Cluster trial Researcher
More informationGUIDELINE COMPARATORS & COMPARISONS:
GUIDELINE COMPARATORS & COMPARISONS: Direct and indirect comparisons Adapted version (2015) based on COMPARATORS & COMPARISONS: Direct and indirect comparisons - February 2013 The primary objective of
More informationthe standard deviation (SD) is a measure of how much dispersion exists from the mean SD = square root (variance)
Normal distribution The normal distribution is also known as the Gaussian distribution or 'bell-shaped' distribution. It describes the spread of many biological and clinical measurements Properties of
More informationTreatment effect estimates adjusted for small-study effects via a limit meta-analysis
Treatment effect estimates adjusted for small-study effects via a limit meta-analysis Gerta Rücker 1, James Carpenter 12, Guido Schwarzer 1 1 Institute of Medical Biometry and Medical Informatics, University
More informationUNCORRECTED PROOFS. Software for Publication Bias. Michael Borenstein Biostat, Inc., USA CHAPTER 11
CHAPTER Software for Publication Bias Michael Borenstein Biostat, Inc., USA KEY POINTS Various procedures for addressing publication bias are discussed elsewhere in this volume. The goal of this chapter
More informationAssessing publication bias in genetic association studies: evidence from a recent meta-analysis
Psychiatry Research 129 (2004) 39 44 www.elsevier.com/locate/psychres Assessing publication bias in genetic association studies: evidence from a recent meta-analysis Marcus R. Munafò a, *, Taane G. Clark
More informationSystematic reviews and meta-analyses of observational studies (MOOSE): Checklist.
Systematic reviews and meta-analyses of observational studies (MOOSE): Checklist. MOOSE Checklist Infliximab reduces hospitalizations and surgery interventions in patients with inflammatory bowel disease:
More informationDuring the past several decades, the modeling of stroke in
Empirical Evidence of Bias in the Design of Experimental Stroke Studies A Metaepidemiologic Approach Nicolas A. Crossley, MSc; Emily Sena, BSc; Jos Goehler; Jannekke Horn, MD; Bart van der Worp, MD; Philip
More informationChanges to NIH grant applications:
Changes to NIH grant applications: Changes to application guide instructions for preparing the Research Strategy. Three new required sections have to be incorporated into the 12 page limit of the Research
More informationResults. NeuRA Forensic settings April 2016
Introduction Prevalence quantifies the proportion of individuals in a population who have a disease during a specific time period. Many studies have reported a high prevalence of various health problems,
More informationClinical research in AKI Timing of initiation of dialysis in AKI
Clinical research in AKI Timing of initiation of dialysis in AKI Josée Bouchard, MD Krescent Workshop December 10 th, 2011 1 Acute kidney injury in ICU 15 25% of critically ill patients experience AKI
More informationCochrane Pregnancy and Childbirth Group Methodological Guidelines
Cochrane Pregnancy and Childbirth Group Methodological Guidelines [Prepared by Simon Gates: July 2009, updated July 2012] These guidelines are intended to aid quality and consistency across the reviews
More informationHow to Conduct a Meta-Analysis
How to Conduct a Meta-Analysis Faculty Development and Diversity Seminar ludovic@bu.edu Dec 11th, 2017 Periodontal disease treatment and preterm birth We conducted a metaanalysis of randomized controlled
More informationResults. NeuRA Motor dysfunction April 2016
Introduction Subtle deviations in various developmental trajectories during childhood and adolescence may foreshadow the later development of schizophrenia. Studies exploring these deviations (antecedents)
More informationEmpirical evidence on sources of bias in randomised controlled trials: methods of and results from the BRANDO study
Empirical evidence on sources of bias in randomised controlled trials: methods of and results from the BRANDO study Jonathan Sterne, University of Bristol, UK Acknowledgements: Tony Ades, Bodil Als-Nielsen,
More informationEssential Skills for Evidence-based Practice Understanding and Using Systematic Reviews
J Nurs Sci Vol.28 No.4 Oct - Dec 2010 Essential Skills for Evidence-based Practice Understanding and Using Systematic Reviews Jeanne Grace Corresponding author: J Grace E-mail: Jeanne_Grace@urmc.rochester.edu
More informationPROTOCOL FORMAT SYSTEMATIC REVIEW ANIMAL INTERVENTION STUDIES
PROTOCOL FORMAT SYSTEMATIC REVIEW ANIMAL INTERVENTION STUDIES Item # Section/topic General 1. Title of the review BY SYRCLE (WWW.SYRCLE.NL) VERSION 0.9 (APRIL 2014) Description Ischemic preconditioning
More informationResults. NeuRA Family relationships May 2017
Introduction Familial expressed emotion involving hostility, emotional over-involvement, and critical comments has been associated with increased psychotic relapse in people with schizophrenia, so these
More informationDisclosures. An Introduction to Meta Analysis. Biography, SL Norris 2/20/2012
An Introduction to Meta Analysis Susan L. Norris, MD, MPH, MS Associate Professor Oregon Health & Science University Portland, OR norriss@ohsu.edu Biography, SL Norris MD, MS, University of Alberta MPH,
More informationMethod. NeuRA Paliperidone August 2016
Introduction Second generation antipsychotics (sometimes referred to as atypical antipsychotics) are a newer class of antipsychotic medication than first generation typical antipsychotics. Second generation
More informationResearch Synthesis and meta-analysis: themes. Graham A. Colditz, MD, DrPH Method Tuuli, MD, MPH
Research Synthesis and meta-analysis: themes Graham A. Colditz, MD, DrPH Method Tuuli, MD, MPH Today Course format Goals, competencies Overview of themes for the class SRMA M19-551 Course Format Lectures»
More informationEfficacy of Antidepressants in Animal Models of Ischemic Stroke A Systematic Review and Meta-Analysis
Efficacy of Antidepressants in Animal Models of Ischemic Stroke A Systematic Review and Meta-Analysis Sarah K. McCann, PhD; Cadi Irvine, BSc; Gillian E. Mead, MD, FRCP; Emily S. Sena, PhD; Gillian L. Currie,
More informationResults. NeuRA Treatments for dual diagnosis August 2016
Introduction Many treatments have been targeted to improving symptom severity for people suffering schizophrenia in combination with substance use problems. Studies of dual diagnosis often investigate
More informationRecent developments for combining evidence within evidence streams: bias-adjusted meta-analysis
EFSA/EBTC Colloquium, 25 October 2017 Recent developments for combining evidence within evidence streams: bias-adjusted meta-analysis Julian Higgins University of Bristol 1 Introduction to concepts Standard
More informationFOCUS: Fluoxetine Or Control Under Supervision Results. Martin Dennis on behalf of the FOCUS collaborators
FOCUS: Fluoxetine Or Control Under Supervision Results Martin Dennis on behalf of the FOCUS collaborators Background Pre clinical and imaging studies had suggested benefits from fluoxetine (and other SSRIs)
More informationExamining Relationships Least-squares regression. Sections 2.3
Examining Relationships Least-squares regression Sections 2.3 The regression line A regression line describes a one-way linear relationship between variables. An explanatory variable, x, explains variability
More informationDescribe what is meant by a placebo Contrast the double-blind procedure with the single-blind procedure Review the structure for organizing a memo
Business Statistics The following was provided by Dr. Suzanne Delaney, and is a comprehensive review of Business Statistics. The workshop instructor will provide relevant examples during the Skills Assessment
More informationData extraction. Specific interventions included in the review Dressings and topical agents in relation to wound healing.
Systematic reviews of wound care management: (2) dressings and topical agents used in the healing of chronic wounds Bradley M, Cullum N, Nelson E A, Petticrew M, Sheldon T, Torgerson D Authors' objectives
More informationLearning Objectives 9/9/2013. Hypothesis Testing. Conflicts of Interest. Descriptive statistics: Numerical methods Measures of Central Tendency
Conflicts of Interest I have no conflict of interest to disclose Biostatistics Kevin M. Sowinski, Pharm.D., FCCP Last-Chance Ambulatory Care Webinar Thursday, September 5, 2013 Learning Objectives For
More informationUnit 1 Exploring and Understanding Data
Unit 1 Exploring and Understanding Data Area Principle Bar Chart Boxplot Conditional Distribution Dotplot Empirical Rule Five Number Summary Frequency Distribution Frequency Polygon Histogram Interquartile
More information9/4/2013. Decision Errors. Hypothesis Testing. Conflicts of Interest. Descriptive statistics: Numerical methods Measures of Central Tendency
Conflicts of Interest I have no conflict of interest to disclose Biostatistics Kevin M. Sowinski, Pharm.D., FCCP Pharmacotherapy Webinar Review Course Tuesday, September 3, 2013 Descriptive statistics:
More informationSchool of Dentistry. What is a systematic review?
School of Dentistry What is a systematic review? Screen Shot 2012-12-12 at 09.38.42 Where do I find the best evidence? The Literature Information overload 2 million articles published a year 20,000 biomedical
More informationNeuRA Obsessive-compulsive disorders October 2017
Introduction (OCDs) involve persistent and intrusive thoughts (obsessions) and repetitive actions (compulsions). The DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition) defines
More informationStatistics is the science of collecting, organizing, presenting, analyzing, and interpreting data to assist in making effective decisions
Readings: OpenStax Textbook - Chapters 1 5 (online) Appendix D & E (online) Plous - Chapters 1, 5, 6, 13 (online) Introductory comments Describe how familiarity with statistical methods can - be associated
More informationDeterminants of quality: Factors that lower or increase the quality of evidence
Determinants of quality: Factors that lower or increase the quality of evidence GRADE Workshop CBO, NHG and Dutch Cochrane Centre CBO, April 17th, 2013 Outline The GRADE approach: step by step Factors
More informationUniversity of Wollongong. Research Online. Australian Health Services Research Institute
University of Wollongong Research Online Australian Health Services Research Institute Faculty of Business 2011 Measurement of error Janet E. Sansoni University of Wollongong, jans@uow.edu.au Publication
More informationResults. NeuRA Herbal medicines August 2016
Introduction have been suggested as a potential alternative treatment which may positively contribute to the treatment of schizophrenia. Herbal therapies can include traditional Chinese medicines and Indian
More informationCHL 5225 H Advanced Statistical Methods for Clinical Trials. CHL 5225 H The Language of Clinical Trials
CHL 5225 H Advanced Statistical Methods for Clinical Trials Two sources for course material 1. Electronic blackboard required readings 2. www.andywillan.com/chl5225h code of conduct course outline schedule
More informationEPSE 594: Meta-Analysis: Quantitative Research Synthesis
EPSE 594: Meta-Analysis: Quantitative Research Synthesis Ed Kroc University of British Columbia ed.kroc@ubc.ca March 28, 2019 Ed Kroc (UBC) EPSE 594 March 28, 2019 1 / 32 Last Time Publication bias Funnel
More informationGuidance Document for Claims Based on Non-Inferiority Trials
Guidance Document for Claims Based on Non-Inferiority Trials February 2013 1 Non-Inferiority Trials Checklist Item No Checklist Item (clients can use this tool to help make decisions regarding use of non-inferiority
More informationMeta-analysis: Methodology
Meta-analysis: Methodology Example: Assessment of cardiovascular safety profile of new generation BCR-ABL TKIs in patients with CML Haguet Hélène 04/03/2016 Meta-analysis = statistical combination of results
More informationSupplementary Information for Duration of dual antiplatelet therapy after drug-eluting stent
Supplementary Information for Duration of dual antiplatelet therapy after drug-eluting stent implantation: Meta-analysis of large randomised controlled trials Title of manuscript: Duration of dual antiplatelet
More informationStatistics is the science of collecting, organizing, presenting, analyzing, and interpreting data to assist in making effective decisions
Readings: OpenStax Textbook - Chapters 1 5 (online) Appendix D & E (online) Plous - Chapters 1, 5, 6, 13 (online) Introductory comments Describe how familiarity with statistical methods can - be associated
More informationCritical appraisal: Systematic Review & Meta-analysis
Critical appraisal: Systematic Review & Meta-analysis Atiporn Ingsathit MD.PhD. Section for Clinical Epidemiology and biostatistics Faculty of Medicine Ramathibodi Hospital Mahidol University What is a
More informationInstruments for Assessing Risk of Bias and Other Methodological Criteria of Published Animal Studies: A Systematic Review
1 Instruments for Assessing Risk of Bias and Other Methodological Criteria of Published Animal Studies: A Systematic Review January 14, 2015 David Krauth 1, Tracey Woodruff 2, Lisa Bero1, 3, 4 1 University
More informationDescribe what is meant by a placebo Contrast the double-blind procedure with the single-blind procedure Review the structure for organizing a memo
Please note the page numbers listed for the Lind book may vary by a page or two depending on which version of the textbook you have. Readings: Lind 1 11 (with emphasis on chapters 5, 6, 7, 8, 9 10 & 11)
More informationPROGRAMMA DELLA GIORNATA
PROGRAMMA DELLA GIORNATA si riprendono i concetti della volta precedente compiti dati da fare a casa si richiama il programma del corso 1.1.1. Studi integrativi 1.1.2. Revisioni sistematiche 1.1.4.1. TEST
More informationDatabase of Abstracts of Reviews of Effects (DARE) Produced by the Centre for Reviews and Dissemination Copyright 2017 University of York.
A comparison of the cost-effectiveness of five strategies for the prevention of non-steroidal anti-inflammatory drug-induced gastrointestinal toxicity: a systematic review with economic modelling Brown
More informationSix Sigma Glossary Lean 6 Society
Six Sigma Glossary Lean 6 Society ABSCISSA ACCEPTANCE REGION ALPHA RISK ALTERNATIVE HYPOTHESIS ASSIGNABLE CAUSE ASSIGNABLE VARIATIONS The horizontal axis of a graph The region of values for which the null
More informationIntroduction to systematic reviews/metaanalysis
Introduction to systematic reviews/metaanalysis Hania Szajewska The Medical University of Warsaw Department of Paediatrics hania@ipgate.pl Do I needknowledgeon systematicreviews? Bastian H, Glasziou P,
More informationSupplementary webappendix
Supplementary webappendix This webappendix formed part of the original submission and has been peer reviewed. We post it as supplied by the authors. Supplement to: Ray K K, Seshasai S R K, Wijesuriya S,
More informationGambling attitudes and misconceptions
FINDINGS The results have been presented showing the effect sizes of interventions. When heterogeneity was absent the studies were pooled. However, the confidence intervals should be considered with caution.
More informationThis is a repository copy of Practical guide to sample size calculations: superiority trials.
This is a repository copy of Practical guide to sample size calculations: superiority trials. White Rose Research Online URL for this paper: http://eprints.whiterose.ac.uk/97114/ Version: Accepted Version
More informationImproving the Analysis and Interpretation of Vascular Prevention Trials
Improving the Analysis and Interpretation of Vascular Prevention Trials Philip M W Bath Stroke, Division of Clinical Neuroscience University of Nottingham Work with Stuart Pocock, Chamila Geeganage, Lisa
More informationRobert M. Jacobson, M.D. Department of Pediatric and Adolescent Medicine Mayo Clinic, Rochester, Minnesota
How to Conduct a Systematic Review: A Workshop 24 th Annual Primary Care Research Methods & Statistics Conference, San Antonio, Texas Saturday, December 3, 2011 Robert M. Jacobson, M.D. Department of Pediatric
More informationChapter 1: Exploring Data
Chapter 1: Exploring Data Key Vocabulary:! individual! variable! frequency table! relative frequency table! distribution! pie chart! bar graph! two-way table! marginal distributions! conditional distributions!
More informationSystematic review with multiple treatment comparison metaanalysis. on interventions for hepatic encephalopathy
Systematic review with multiple treatment comparison metaanalysis on interventions for hepatic encephalopathy Hepatic encephalopathy (HE) is a reversible neuropsychiatric syndrome associated with severe
More informationTitle: The efficacy of fish oil supplements in the treatment of depression: food for thought
Title: The efficacy of fish oil supplements in the treatment of depression: food for thought Response to: Meta-analysis and meta-regression of omega-3 polyunsaturated fatty acid supplementation for major
More informationReadings: Textbook readings: OpenStax - Chapters 1 11 Online readings: Appendix D, E & F Plous Chapters 10, 11, 12 and 14
Readings: Textbook readings: OpenStax - Chapters 1 11 Online readings: Appendix D, E & F Plous Chapters 10, 11, 12 and 14 Still important ideas Contrast the measurement of observable actions (and/or characteristics)
More informationBusiness Statistics Probability
Business Statistics The following was provided by Dr. Suzanne Delaney, and is a comprehensive review of Business Statistics. The workshop instructor will provide relevant examples during the Skills Assessment
More informationHow to do a meta-analysis. Orestis Efthimiou Dpt. Of Hygiene and Epidemiology, School of Medicine University of Ioannina, Greece
How to do a meta-analysis Orestis Efthimiou Dpt. Of Hygiene and Epidemiology, School of Medicine University of Ioannina, Greece 1 Overview (A brief reminder of ) What is a Randomized Controlled Trial (RCT)
More informationBiostatistics II
Biostatistics II 514-5509 Course Description: Modern multivariable statistical analysis based on the concept of generalized linear models. Includes linear, logistic, and Poisson regression, survival analysis,
More information