meta分析资料全集之SystematicReviews

SystematicReviews&

Meta-AnalysisAn

OverviewWhatisaSystematicReview?“Areviewthatisconductedaccordingtoclearlystated,scientificresearchmethods,andisdesignedtominimizebiasesanderrorsinherenttotraditional,narrativereviews.”

Margaliot,

Zvi,KevinC.Chung.SystematicReviews:APrimerforPlasticSurgeryResearch.PRSJournal.120/7(2007)Whatisthesignificanceof

SystematicReviews?Thelargeamountofmedicalliterature

requirescliniciansandresearchersaliketo

relyonsystematicreviews

inordertomakeaninformeddecision.SystematicReviewsminimizebias.“Asystematicreviewisamorescientificmethodofsummarizingliteraturebecausespecificprotocolsareusedtodeterminewhichstudieswillbeincludedinthereview.”

KevinC.Chung,MD,Patricia

B.Burns,MPH,H.MyraKim,ScD,“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.p.1671WhyareSystematicReviewsNecessary?“Thevolumeofpublishedmaterialmakesitimpracticalforanindividualcliniciantoremainuptodateonavarietyofcommonconditions.Thisisfurthercomplicatedwhenindividualstudiesreportconflictingconclusions,aproblemthatisprevalentwhensmallpatientsamplesandretrospectivedesignsareused.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch”.PRSJournal.120/7(2007)p.1834KeyCharacteristicsofSystematicReviewsClearlystatedtitleandobjectivesComprehensivestrategytosearchforrelevantstudies(unpublishedandpublished)ExplicitandjustifiedcriteriafortheinclusionorexclusionofanystudyClearpresentationofcharacteristicsofeachstudyincludedandananalysisofmethodologicalqualityComprehensivelistofallstudiesexcludedandjustificationforexclusion

LindaN.Meurer,MD,MPHDepartmentofFamilyandCommunityMedicine.“SystematicSynthesisoftheLiterature:IntroductiontoMeta-analysis”.

PowerPointPresentation.

CharacteristicsofSystematicReviews(cont.)Clearanalysisoftheresultsoftheeligiblestudiesstatisticalsynthesisofdata(meta-analysis)ifappropriateandpossible;orqualitativesynthesis

Structuredreportofthereviewclearlystatingtheaims,describingthemethodsandmaterialsandreportingtheresults

LindaN.Meurer,MD,MPHDepartmentofFamilyandCommunityMedicine.“SystematicSynthesisoftheLiterature:IntroductiontoMeta-analysis”.

PowerPointPresentation.AnauthorofagoodSystematicReview…FormulatesaQuestionConductsaLiteratureSearchRefinesthesearchbyapplyingpredeterminedinclusionandexclusioncriteriaExtractstheappropriatedataandassesstheirqualityandvaliditySynthesizes,interprets,andreportsdataHypothesis“Asystematicreviewshouldbebasedonprinciplesofhypothesistesting,andthehypothesesmustbeconceivedapriori.”

Margaliot,

Zvi,KevinC.Chung.SystematicReviews:APrimerforPlasticSurgeryResearch.PRSJournal.120/7(2007)p.1836FocusoftheQuestionThestructuredquestionwilldeterminetheinclusionandexclusioncriteria:Whatisthepopulationofinterest?Whataretheinterventions?Whataretheoutcomesofinterest?Whatstudydesignsareappropriate?Inclusion/ExclusionCriteria“Oncethestudyquestionisformalized,theauthorsmustcomposeacomprehensivelistofinclusionandexclusioncriteria.”“Toavoidselectionbias,inclusionandexclusioncriteriashouldbeagreeduponandformalizedbeforedata

extractionandanalysis.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1836LiteratureSearch“Acomprehensiveandreproducibleliteraturesearchisthefoundationofasystematicreview.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1837LiteratureSearchChallengesDatabaseBias-“Nosingledatabaseislikelytocontainallpublishedstudiesonagivensubject.”PublicationBias-selectivepublication

ofarticlesthatshowpositivetreatmentofeffectsandstatisticalsignificance.Hence,itisimportanttosearchforunpublishedstudiesthroughamanualsearchofconferenceproceedings,correspondencewithexperts,andasearchofclinicaltrialsregistries.

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1837LiteratureReviewChallenges(cont.)English-languagebias-occurswhenreviewersexcludepaperspublishedinlanguagesotherthanEnglishCitationbias-

occurswhenstudieswithsignificantorpositiveresultsarereferencedinotherpublications,comparedwithstudieswithinconclusiveornegativefindingsDataCollection“Thelistofdatatobeextractedshouldbeagreeduponaprioriconsensusduringthedesignstageofthestudy.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1839DataCollection(cont.)Collecteddataincludes:StudycharacteristicsSampledemographicsOutcomedataDataCollection(cont.)“Itisnecessarytodesignareview-specificdataextractionform,sothatthesamedataareextractedfromeachstudyandmissingdataareclearlyapparent.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1839DataCollection(cont.) “Toensurethatdataextractionisaccurateandreproducible,itshouldbeperformedbyatleasttwoindependentreaders.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1839QualityAssessment“Thevalidityofasystematicreviewultimatelydependsonthescientificmethodoftheretrievedstudiesandthereportingofdata.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1839QualityAssessment(cont.)RandomizedControlled

Trials(RCT):RCTareconsideredtobemorerigorousthanobservationalstudiesAreviewbasedonwell-designedRCTwilllikelybemorevalidandaccuratethanareviewbasedonobservationalstudiesorcasereports

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1839QualityAssessment(cont.)“Themostcommonwaytoassessandreportstudyqualityhasbeenusingacomposite,numericalscoringinstrument.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1839QualityAssessment(cont.)“Morethan35differentqualityassessmentinstrumentshavebeenpublishedintheliterature,andmostaredesignedforrandomizedclinicaltrials.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1839Jadadscore&Chalmersscore“TheJadadscoreandtheT.C.Chalmersscorearetwoexamplesofqualityassessmentinstruments.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1839JadadscoreRandomization(2pointspossible)1pointifstudydescribedasrandomizedAdd1pointifrandomizationmethoddescribedandappropriate(e.g.randomnumbersgenerated)Deduct1pointrandomizationdescribedandinappropriate

Double-blinding(2pointspossible)1pointifstudydescribedasdouble-blindedAdd1pointifmethodofdouble-blindingdescribedandappropriateDeduct1pointifdouble-blindingdescribedandinappropriate

Withdrawals(1pointpossible)Give1pointforadescriptionofwithdrawalsanddrop-outs

LindaN.Meurer,MD,MPHDepartmentofFamilyandCommunityMedicine.“SystematicSynthesisoftheLiterature:IntroductiontoMeta-analysis”.

PowerPointPresentation.JadadScoreExampleStudyRandomizationBlindingDrop-out1+++++2+++03++0+4+++++50+++DataSynthesis “Oncethedatahavebeenextractedandtheirqualityandvalidityassessed,theoutcomesofindividualstudieswithinasystematicreviewmaybepooledandpresentedassummaryoutcomeoreffect”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1840DataSynthesis(cont.)Theauthorssummarizeheterogeneousdataqualitatively“Datathatareveryconflictingandwidelyvariableshouldnot,undermostcircumstances,becombinednumerically.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1840Whencandata

inasystematicreviewbesynthesizednumerically?WhendataareNOTtoosparse,oftoolowqualityortooheterogeneous

Forexample:thepatients,interventionsandoutcomesineachoftheincludedstudiesaresufficientlysimilarMeta-Analysis“Meta-analysisisastatisticaltechniqueforcombiningtheresultsofindependent,butsimilar,studiestoobtainanoverallestimateoftreatmenteffect.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1840Meta-Analysis(cont.)“Whileallmeta-analysesarebasedonsystematicreviewofliterature,notallsystematicreviewsnecessarilyincludemeta-analysis.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1840Meta-Analysis (cont.)“Ifameta-analysisistobeincludedinasystematicreview,anexperiencedstatisticianoranepidemiologistshouldbeconsultedduringallphasesofthestudy.”

Margaliot,

Zvi,KevinC.Chung.“SystematicReviews:APrimerforPlasticSurgeryResearch.”PRSJournal.120/7(2007)p.1840Meta-analysis(cont.)“Protocolsforthereportingofmeta-analysisresultsweredevelopedforRCTs(QualityofReportsofMeta-analysis[QUOROM]andObservationalStudiesinEpidemiology[MOOSE].”

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1672ProtocolsThepurposeof

QUOROMandMOOSE

guidelinesistoprovideproperproceduresforconductingameta-analysisandtostandardizethemethodsofreportingameta-analysis.

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1672StepsofMeta-analysisDefinetheResearchQuestionPerformtheliteraturesearchSelectthestudiesExtractthedataAnalyzethedataReporttheresults

Meta-analysis:TheResearchQuestion“Commonquestionsaddressedinmeta-analysisarewhetheronetreatmentismoreeffectivethananotherorifexposuretoacertainagentwillresultindisease.”

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1672Meta-analysis:PerformingtheLiteratureSearch“Theliteraturesearchisacriticalstepinthemeta-analysisandoftenthemostdifficultpart.”

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1672Meta-analysis:TheLiteratureSearch(cont.)“TheresearchershouldsearchmorethanjustMEDLINEtoensureacomprehensivesearch.”

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1673Meta-analysis:TheLiteratureSearch(cont.)SearchforpublishedstudiesinMEDLINE,EMBASE,andCINAHL.SearchforunpublishedclinicaltrialsintheCochraneCentralRegisterofControlledTrialsMeta-analysis:StudySelection“Theinclusionandexclusioncriteriaforstudiesneedstobedefinedatthebeginning,duringthedesignstageofthemeta-analysis.”“Factorsdetermininginclusionintheanalysisarestudydesign,populationcharacteristics,typeoftreatmentorexposure,andoutcomemeasures.”

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1673Meta-analysis:StudySelection(cont.)Meta-analysis

needstobedocumented“Oneshouldkeeptrackofthestudiesincludedandexcludedateachstepoftheselectionprocesstodocumenttheselectionprocess.”

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1673Meta-analysis:StudySelection(cont.)“TheQUOROMguidelinesforreportingameta-analysisrequeststhatinvestigatorsprovideaflowdiagramoftheselectionprocess.”

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1673TheValidityofaMeta-analysis“Thevalidityofameta-analysisdependsonthequalityofthestudiesincluded,andanassessmentofqualityisanecessarypartoftheprocess.”

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1674Meta-analysis:ExtractingtheData“Thetypeofdatatobeextractedfromeachstudyshouldbedeterminedinthedesignphaseandastandardizedformisconstructedtorecordthedata.”

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1674Meta-analysis:DataWhataretheexamplesofdatacommonlyextracted?Studydesign,descriptionsofstudygroups,diagnosticinformation,treatments,lengthoffollow-upevaluation,andoutcomemeasures.Meta-analysis:Data“Thedifficultywithdataextractionisthatstudiesoftenusedifferentoutcomemetrics,whichmakecombiningthedataawkward.Thedatashouldbeconvertedtoauniformmetricforpooling.”

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1674Meta-analysis:AnalyzingtheDataThereare2statisticalmodelsusedinameta-analysis:

FixedeffectsRandomeffectsTheFixedEffectsModel“Thefixed-effectsmodelassumesthatthetrueeffectoftreatmentisthesameforeverystudy.”

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1675TheRandomEffectsModel“Therandomeffectsmodelassumesthatthetrueeffectestimateforeachstudyvary.”

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1672Meta-analysis:ReportingtheResultsAmeta-analysisshouldinclude:Atitle,abstract,anintroductionMethods,results,anddiscussionsectionsTheIntroduction“Theintroductionshouldindicate

theclinicalquestionofinterest,thehypothesisbeingtested,thetypesoftreatmentorexposurebeingstudied,thestudydesignstobeincluded,andadescriptionofthestudypopulation.”

KevinC.Chung,MD,PatriciaB.Burns,MPH,H.MyraKim,ScD.

“ClinicalPerspective:APracticalGuidetoMeta-Analysis.”TheJournalofHandSurgery.

Vol.31ANo.10December2006.

p.1675TheMethodsSection“Themethodssectionshould

describetheliteraturesearch,specificallythedatabasesused,andifthesearchwasrestrictedinanyway.Theselectionprocessforarticles,qualityassessment,methodsofdata

abstraction,andsynthesis.”

KevinC.Chung,MD,