循证医学EBM的过去现在与未来.ppt
實實 證證 醫醫 學學EBM過去、現在與未來過去、現在與未來林口長庚醫院 實證醫學中心 余光輝醫師Medical Education in the New Century醫學人文教育醫學人文教育BioinformaticsPatient-centered careProblem-based learningEvidence-based medicine實證醫學實證醫學(EBM,Evidence-based Medicine)以流行病學和統計學的方法,從龐大的醫學資料庫中嚴格評讀、綜合分析並找出值得信賴的部分,並將所能獲得的最佳文獻證據,應用於臨床工作中,使病人得到最佳的照顧。實證醫學沿革實證醫學沿革1972年英國臨床流行病學者Archie Cochrane提出實證醫學的概念。所有醫療行為都應有嚴謹研究且證實為有效的根據,才能將醫療資源做最有效的運用,並強調 Randomized controlled trials 的重要性。1992英國國家衛生部成立實證醫學中心,並以Archie Cochrane之名命名,進而促使1993年Cochrane Collaboration的設立。(Iain Chalmers,David Sackett)Lancet 曾把Cochrane Collaboration比作臨床醫學的人類基因組計劃Dr.Sydney Burwell,Dean of Harvard Medical SchoolHalfofwhatyouaretaughtasmedicalstudentswillintenyearshavebeenshowntobewrong.Andthetroubleis,noneofyourteachersknowswhichhalf.Use of current best evidence in making decisions about the care of individual patientsNot only a skill but also an attitude changeConscientious,explicit,andjudicioususeofcurrentbestevidenceinmakingdecisionsaboutindividualpatients.ArchieCochrane1972E B M實證醫學的實施實證醫學的實施醫師在處置病人所面臨的問題時有許多不確定性,這種不確定性常以機率來表示。機率的估計,可以來自個人的經驗,但是免不了有某種程度的偏差,因此我們必須借重客觀可信的臨床研究結果,來作為照顧病人的主要依據。實證醫學是兼具科學方法,及人文特質的診療模式,且以病人為中心,以問題為導向的精神,正確的應用可以提昇整體的醫療品質。隨著資訊科技的發展,醫師與病人可以很容易的從公正、可靠的資訊中獲得以實證為基礎的相關訊息。為了要跟得上醫學最新的腳步及病人被告知的權利,提供高品質的醫療照護,實證醫學應為醫學教育的核心原則。進階學習進階學習目前國外推動實證醫學著名的單位加拿大McMasterUniversity的HIRU(HealthInformationResearchUnit)是CochraneCollaboration的重鎮lhttp:/英國OxfordUniversity的CentreforEvidence-BasedMedicinel美國AmericanCollegeofPhysician(ACP),在全球資訊網出版ACPJournalClubOnlinelhttp:/Step1.Convertingtheneedforinformation(aboutprevention,diagnosis,prognosis,therapy,causation,etc.)intoananswerablequestion.Step2.Searchingthebestevidencewithwhichtoanswerthatquestion.Step3.Criticallyappraisingtheevidenceforitsvalidity(closenesstothetruth),impact(sizeoftheeffect),andapplicability(usefulnessinourclinicalpractice).Step4.Integratingtheevidencewithourclinicalexpertiseandpatientsuniquebiology,valuesandcircumstances.Step5.Evaluatingoureffectivenessandefficiencyinexecutingsteps1-4andseekingwaystoimprovethembothfornexttime.實證醫學的五大進行步驟FiveStepstoPracticeEBM The Evidence PyramidAnimal researchIn vitro(test tube)researchCase series/ReportsIdeas,Editorials,OpinionsCase Control StudiesCohort studiesRandomized Controlled StudiesRandomized Controlled Double Blind Studies Meta-analysis實證醫學的五個進行步驟實證醫學的五個進行步驟1.由個案的臨床資料尋找能解答、且具體的臨床問題。askingananswerablequestion2.尋找相關的醫學證據包括各種文獻及醫學資料庫,發表及未發表的研究成果。searchingthebestevidence3.評估各種醫學報告的可信度及臨床相關性,並作成結論。criticalappraisaltheevidence4.將結論應用於實際患者的治療。臨床應用5.評估治療的效果。evaluationAsking Answerable Clinical QuestionsWell-built clinical question“Background”questionlAskgeneralknowledgeaboutadisorderlHavetwoessentialcomponents:lAquestionroot(who,what,why,when)withaverblAdisorder,oranaspectofadisorder“Foreground”questionlAskforspecificknowledgeaboutmanagingpatientswithadisorderlHavefour(orthree)essentialcomponents:l1.Patientand/orprobleml2.Intervention(treatment)l3.Comparisoninterventionl4.ClinicaloutcomesPatientWhoisthepatientorwhatistheproblembeingaddressed?InterventionWhatistheintervention?ComparisonWhatarethealternatives?OutcomeWhataretheoutcomes?There are four elements of a well-formulated questionSearching The Best Evidence尋找最佳實證資料一是研究論文資料庫(primary journals or databases)如 Medline,NEJM,Lancet或是直接使用實證醫學資料庫(secondary journals or databases)ACP journal club,Cochrane.盡量搜尋與病人問題相同且證據等級(level of evidence)較高之文獻,再謹慎的評讀與評估其在此人問題的適用性。實證醫學資料庫查詢的優點實證醫學資料庫查詢的優點1.文獻資料可經由網路快速查詢,最新的醫學進展可以立即見於網路,比傳統教科書更update。2.以實證醫學特有的文獻格式,表達資料取得方法及重要結果,醫師不須花很多時間便能了解其要旨,與長篇大論的傳統文獻不同。3.利用這些資源,醫師可以節省閱讀大量文獻的時間。實證醫學臨床流行病學醫學資訊學團隊合作實證醫學主要的四個資料庫 1.ACP Journal Club:含括ACP Journal Club(American College of Physicians,美國內科醫師學會出版)與Evidence-Based Medicine(ACP 與 British Medical Journal Group合作出版)兩種出版品,每月至少過濾50種以上之核心期刊,搜尋最佳之原始與評論性文章,結構化整理摘要出其中重要實證所得。2.DARE:DatabaseofAbstractsofReviewsofEffectiveness收錄評論性文章的全文型資料庫,由 National Health Services Centre for Reviews and Dissemination(NHS CRD)組織出版,此一組織針對部份經過評估、挑選有學術價值的醫學期刊中選出系統性評論的文章,並將之集合而成 DARE。3.CDSR:CochraneDatabaseofSystematicReviews為Cochrane 合作研究機構(Cochrane Collaboration)所出版,其為一個人與機構共同組成之國際性網路組織,有系統的研究上百種期刊文獻,專門從事有系統的評論儲備、維護和傳遞影響醫療保健相關之業務主題性評論。4.CCTR:CochraneCentralRegisterofControlledTrials超過 300,000筆有關健康保健的控制實驗樣品參考型書目資料,內容包括 RCTRandomized Controlled Trials及 CCT Clinical Controlled Trials。由 Cochrane groups 及其單位組織將 Medline 及 EMBASE 檢索出來的隨機樣品文獻登記集中而成。本院EBM資料庫比較ACP Journal ClubDARECDSRCCTR出版者美國內科醫師學會出版NHSCRDCochraneCochrane資料來源每月至少過濾50種以上之核心期刊,例:NEJM、JAMA、Lancet、Circulation.等經過評估、挑選有學術價值的醫學期刊、Medline、CINAL、Biosis、ERIC、PsycINFO、上百種期刊文獻Medline、EMBASE、其他電子資料庫資料庫類型全文型全文型全文型書目型實證醫學的參考書籍常用實證醫學網路連結常用實證醫學網路連結CGMH長庚醫院圖書館資料庫PubMed:http:/1.ACPJournalClub:http:/(1-4,7項需由圖書館進入)2.CochraneDARE(DatabaseofAbstractsofReviewsofEffects)3.CDSR(CochraneDatabaseofSystematicReviews)CollaborativeReviewGroupshttp:/4.CCTR(CochraneCentralRegisterofControlledTrials):5.Cochranecollaberation介紹6.NGC(NationalGuidelineClearinghouse):http:/guideline.org7.Micromedex(CCIS)為毒物、藥學及急診醫學專業之全文資料庫,每季更新8.CentreforEvidence-BasedMedicine:http:/=http:/cemb.jr2.ox.ac.uk9.加拿大McMasterUniversity的HIRU(HealthInformationResearchUnit)是CochraneCollaboration的重鎮:http:/10.美國的AmericanCollegeofPhysician(ACP):http:/11.Bandolier:http:/12.AHRQwebsite:http/13.InfoPOEMs:http:/14.Otherresources:http:/http:/15.彰化基督教醫院證據醫學中心16.萬芳醫院實證醫學中心17.醫藥衛生研究資訊網(HINT):http:/以上建議由部門版面直接連結較快The Evidence PyramidAnimal researchIn vitro(test tube)researchCase series/ReportsIdeas,Editorials,OpinionsCase Control StudiesCohort studiesRandomized Controlled StudiesRandomized Controlled Double Blind Studies Meta-analysisGrade of RecommendationLevel of EvidenceTherapyA1aSystemicreviewofRCTs1bSingleRCT1cAll-or-noneB2aSystemicreviewofcohortstudies2bCohortstudyorpoorRCT2cOutcomesresearch3aSystemicreviewofcase-controlstudies3bCase-controlstudyC4CaseseriesD5Expertopinion,physiology,benchresearch統計數字會說話統計數字會說話評估時以具體的數字呈現結果評估時以具體的數字呈現結果敏感度(sensitivity)、特異度(specificity)、概似比(likelihood ratio)、檢測前機率(pre-test probability)、檢測後機率(post-test probability)ARR(Absolute risk reduction)=EER(Experimental Event Rate)-CER(Control Event Rate)、Number needed to treat,NNT=1/ARR(增加一位病患得到某種處置好處所需的治療病人數)、相對危險度減少百分比(relative risk reduction,RRR)絕對危險度增加百分比(absolute risk increase,ARI)=EER(Experimental Event Rate)-CER(Control Event Rate)、Number needed to harm,NNH=1/ARI(增加一位受試者罹患某種醫源性傷害的治療病人數)相對危險(Relative risk)、勝算(Odds)、勝算比(Odds ratio)、信賴區間(confidence interval)DiagnosisDiagnostic test (ferritin)Disease(IDA)PresentAbsentPositive731 ab 270Negative 78 cd 1500Sensitivity=a/a+c=731/809=90%Specificity=d/b+d=1500/1770=85%Positive predictive value=a/a+b=731/1001=73%Negative predictive value=d/c+d=1500/1578=95%LR+for a positive result=sens/(1-spec)=90%/15%=6LR-for a negative result=(1-sens)/spec=10%/85%=0.12Pre-test probability(prevalence)=a+c/a+b+c+d=31%Pre-test odds=prevalence/(1-prevalence)=31%/69%=0.45Post-test odds=Pre-test odds Likelihood RatioPost-test probability=Post-test odds/(Post-test odds+1)Calculation of OR/RRTreatmentEventPositiveNegativeExposed(experimental)A=1B=29Not exposed(control)C=9D=21EER=a/a+b=0.033CER=c/c+d=0.30Relative risk=EER/CER=(a/a+b)/(c/c+d)=0.11Experimental event Odds=a/b=0.034Control event Odds=c/d=0.43Relative Odds=Odds ratio=(a/b)/(c/d)=ad/bc=0.08Odd:a ratio of non-events to eventsAsking Answerable Clinical QuestionPatient/ProblemInsulin-dependentdiabeticsInterventionIntensiveinsulinregimenComparisonRegularinsulinregimenOutcomesRetinopathySymptomatichypoglycemiaTreatment EffectsOccurrenceofdiabeticretinopathyat5yearsamonginsulin-dependentdiabeticintheDCCTtrialUsualinsulinregimen(CER:controleventrate):38%Intensiveinsulinregimen(EER:experimentaleventrate):13%Risk Reduction(calculation)Absoluteriskreduction(ARR)=CER-EER=38%-13%=25%Relativeriskreduction(RRR)=CER-EER/CER=25%/38%=66%Numberneededtotreat(NNT)=1/ARR=1/25%=4patientslThe number of patients that need to be treated to prevent one bad outcome or get one good outcome.HarmTheproportionofpatientswithatleastoneepisodeofsymptomatichypoglycemiaUsualinsulinregimen(CER:controleventrate):23%Intensiveinsulinregimen(EER:experimentaleventrate):57%Risk Increase(calculation)Absoluteriskincrease(ARI)=EER-CER=57%-23%=34%Relativeriskincrease(RRI)=EERCER/CER=57%-23%/23%=148%Numberneededtoharm(NNH)=1/ARI=1/0.34=3patients(取整數)lThenumberofpatientsthatneedtobetreatedtocauseonebadoutcome(beingharmed)Treatment of Class III-IV Lupus NephritisMeta-AnalysisTreatment of diffuse proliferative lupus nephritis:A meta-analysis of randomized controlled trialsAmJKidneyDis.2004Feb;43(2):197-208.Cochrane Renal Group Cochrane Database of Systematic Reviews.1,2004.ValuesofRRlessthan1indicateareductioninriskfortheoutcomewiththeexperimentaltreatment.Conversely,valuesofRRmorethan1indicateanincreaseinrisk.The95%CIsareameasureofvariabilityintheprecisionoftheRRestimateanditsstatisticalsignificance.Heterogeneityoftreatmenteffectsbetweenstudieswasinvestigatedbyvisualexaminationofgraphicmeta-analysisplotsandfromtheCochranQ(heterogeneitychi-square)andI2statistic.Thisisaforestplot,withaverticallineat1.0representingequivalenceinriskforanoutcomewithexperimentalandcontroltreatment(nullhypothesis).TheRRforeachoutcomeandits95%CIareindicatedbyasolidsquareandaline.Thesizeofthesolidsquarerepresentsthecontribution(weight)ofthetrialtotheanalysis.Diamond-shapedsymbolsrepresentthesummaryestimatorofoveralleffectpoolingtheweightedeffectofindividualRCTs.實證醫學發展的重點實證醫學發展的重點,主要有四大範疇:1.增進醫療決策技能medicaldecisionmakingtechnique2.改善醫療資訊擷取技能accessingmedicalinformation3.嚴格評估醫療資訊及其臨床應用assessingthevalidityofmedicalinformation4.促進專家間之合作,以作隨機對照試驗(RCTrandomizedcontrolledtrials)的研究應用最佳實證文獻,訂出臨床疾病診療的guideline,並促進clinical pathway形成。醫療資源有限,對醫療資源的合理運用,必須利用現有的證據,及使用標準化的規範及流程。大量的醫學知識文獻,使醫療提供者(healthcare-provider)無法消化這些知識。因此在實驗室或臨床研究獲得的知識,與一般醫師真正日常行醫行為之應用之間產生不一致的現象。透過各種疾病的臨床診療指引(clinicalpracticeguideline),使醫療不一致性減低,以提高醫療品質。Clinical Practice Guidelines醫院評鑑暨醫療品質策進會 中央健保局 實證醫學會 國家衛生研究院Resource Centers for GuidelinesNGC-NationalGuidelineClearinghousehttp:/AGREE-appraisalofguidelineresearch&evaluationhttp:/GuidelinesInternationalNetworkSIGN-ScottishIntercollegiateGuidelinesNetworkhttp:/台灣實證醫學暨臨床診療指引平台之建置 國衛院郭耿南教授Decision tree analysis實證醫學應用之障礙實證醫學應用之障礙1.沒有實證、找不到實證沒有實證、找不到實證2.實證之間有矛盾實證之間有矛盾3.實證很難去應用實證很難去應用4.缺乏時間與資源缺乏時間與資源5.缺乏保險給付缺乏保險給付6.臨床診療指引制定費時臨床診療指引制定費時終身學習 醫學教育增加實證醫學訓練發現臨床問題,進而帶動研究風氣將有限的資源運用於具有實證的醫療臨床指引制定(學會、健保局、及醫院)制定各種疾病的臨床診療指引及設立本土醫學資料庫,也是躋身國際舞台所不可或缺,如何整合與發揮國內學界的力量,是本世紀重要的醫學課題實證醫學之展望實證醫學之展望林口長庚醫院 實證醫學中心每年舉行EBM統計教學包括如何評讀論文,設計研究等及EBM introduction各一次,94.03舉行 EBM workshop。實證醫學中心14位成員:朱世明,歐良修,江東和,陳漢明,謝邦鑫,陳敏煜,張鴻,高振益,高國晉,田亞中,陳俊吉,黃兆山,楊宗翰,余光輝。(每月開會)實證醫學指導顧問:醫教會副主委 方基存醫師,婦產科 張廷彰醫師,長庚大學公衛科生統中心 史麗珠博士,醫務管理學系暨工管系 許光宏博士 衛生署92年9月起實施“畢業後一般醫學訓練計劃”,實證醫學課程為基本課程之一,每位PGY1需完成8小時,6-10小時課程。目前PGY1在內科一般醫學訓練時每週二中午12:0013:00於8A-8B間內科會議室做EBM病例討論並請PGY1與臨床教師討論及簽名,歡迎參加。Interpretation of evidence is subjective:it dependents on how you view it.Clinical Practice GuidelinesSystemicallydevelopedstatementstoassistpractitionerandpatientdecisionsaboutappropriatehealthcareforspecificclinicalcircumstances.Purposetomakeexplicitrecommendationswithadefiniteintenttoinfluencewhatcliniciansdo.