隊(duì)列研究-課件

隊(duì)列研究

Cohortstudy1隊(duì)列研究

Cohortstudy

Incidencestudies

Longitudinalstudies

Follow-upstudies

Prospectivestudies發(fā)病率研究縱向研究隨訪研究前瞻性研究2Epidemiologyisthestudyofthe

distribution

and

determinants

ofdiseaseandhealthrelatedstatusinaspecifypopulationandtheapplicationofthisstudytocontrolofhealthproblems.ADictionaryofEpidemiology,2nded.by

Last,J.M19883DescriptiveEpidemiologyHypothesisAnalyticalEpidemiologyJudgingCausalityPreventionStrategiesConceptMapCase-ControlCohortstudyExperimentalEpidemiology

c.s.Ecologyscre4DescriptiveEpidemiologicProcess}WHO

wasaffected?WHERE

weretheyaffected?WHEN

weretheyaffected?HOW

andWHY?5DescriptiveStudies:UsesHypothesisgeneratingSuggestingassociationsEvaluatinginterventioneffectStudyinghealthsituationofpopulation6AnalyticalEpidemiologicProcess}HOW

theway?WHY

reason?Causalinference7Animportantcausalinferencecriteria

Temporality

referstothenecessityforacausetoprecedeaneffectintime.Whatkindofstudysatisfiesthelogisticorder?

Cohortstudy!8

OutlineExampleDesignandimplementDatasortandanalysis

BiasandcontrolAdvantage，limitation概述實(shí)例研究設(shè)計(jì)與實(shí)施資料的整理與分析偏倚及控制優(yōu)點(diǎn)和局限性隊(duì)列研究

CohortStudy9

簡(jiǎn)史概念原理特點(diǎn)目的類型BriefhistoryConcept

PrincipleFeatures

PurposeTypes第一節(jié)概述

Outline10簡(jiǎn)史

Briefhistory起源

OriginsGraunt(17世紀(jì))用橫斷面死亡資料，用壽命表方法構(gòu)建生命史Graunt(17thcentury)usedcross-sectionalmortalitydatatoreconstructlifehistoryusinglife-tablemethodsFarr（19世紀(jì)）將壽命表方法發(fā)展為人群健康的指標(biāo)Farr(19thcentury)advancedtheuseoflife-tablemethodsaanindicatorofpopulationhealth保險(xiǎn)業(yè)研究1870–1899

Insuranceindustrystudy1870–1899

11結(jié)核（20世紀(jì)）

Tuberculosis(20thcentury)WHFrost在有結(jié)核的132個(gè)家庭的隊(duì)列開展第一個(gè)回顧性隊(duì)列研究（1933）WHFrostperformedthefirstretrospectivecohortstudyinacohortof132homeswithtuberculosis（1933）用人年來估計(jì)罹患率Usedperson-yearstoestimateattackrates簡(jiǎn)史

History12Framinghamstudyofcardiovasculardisease,1948-Japaneseatomicbombsurvivors,1946-Britishphysicianstudy,1950s-NursesHealthstudy,1976-Aniline-dyeoccupationalcohort,1954Asbestosexposureandlungcancermortality1965RetrospectivecohortstudiesProspectivecohortstudies13

是將人群按是否暴露某可疑因素及其暴露程度分為不同亞組，追蹤其各自結(jié)局，比較不同亞組結(jié)局率的的差異，從而判定暴露與結(jié)局間有無因果關(guān)聯(lián)及關(guān)聯(lián)大小的一種觀察性研究方法。

Anepidemiologicdesigninwhichtheincidenceofadisease(orcondition)iscomparedamongexposedandunexposedindividuals，tojudgeifthereiscausalrelationshipbetweenexposureandoutcome.

概念

What’sthecohortstudy14CohortStudy

KeyPoint:Presenceorabsenceofriskfactorisdeterminedbeforeoutcomeoccurs.15隊(duì)列Whatisacohort?

Cohort

-Latinwordforoneof10divisionsofaRomanlegionAgroupofindividuals

sharingsameexperiencefollowedupforaspecifiedperiodoftimebirthcohortoccupationalcohort隊(duì)列

拉丁語(yǔ)原意是指古羅馬軍團(tuán)中的一個(gè)分隊(duì)一組人群有共同經(jīng)歷隨訪一特定時(shí)間出生隊(duì)列職業(yè)隊(duì)列1617暴露

指接觸過某種物質(zhì)、具備某種特征或處于某種狀態(tài)。Exposurecontactingsomematerials，withsomefeaturesorbeinginsomestatus.18危險(xiǎn)因素泛指能引起某特定不良結(jié)局,或使其發(fā)生的概率增加的因子，包括個(gè)人行為、生活方式、環(huán)境和遺傳等多方面的因素.Riskfactorreferelementsassociatedwithanincreasedriskofmal-outcomes,includingbehavior,lifestyle,environmentalandgeneticfactorandsoon.19

PrincipleofaCohortStudyBeginwithdisease-freepersonsClassifysubjectsasexposed/unexposedFollowupandrecordoutcomesinbothgroupsCompareoutcomeswithrelativeriskAnalysisassociationbetweenexposureandoutcome從沒有疾病人群開始

將研究對(duì)象分為暴露與非暴露組隨訪并記錄兩組結(jié)局相對(duì)危險(xiǎn)度比較結(jié)果分析暴露與結(jié)局關(guān)系20Source:partiallyadaptedfromWHO,1993R1R0A1A0IncidencerateamongexposedIR1=A1(no.exposedcases)

/R1(totalperson-timeexposed)IncidencerateamongunexposedIR0=A0(no.unexposedcases)/R0(totalperson-timeunexposed)Incidencerateratio(exposedvs.unexposed)=IR1/IR0=(A1/A0)/(R1/R0)PrincipleofaCohortStudy21

Features

特點(diǎn)ObservationalSetupcontrolFromcausetooutcome,appreciatetemporalityConfirmthecasualrelationshipbetweenexposureandoutcome觀察性研究設(shè)立對(duì)照由因到果，符合時(shí)間順序能確證暴露與結(jié)局間因果關(guān)系22VerifythehypothesisofcauseofdiseaseEvaluatetheeffectofpreventionandcontrolStudythenaturalhistoryofdiseaseSurveillancepostmarketofnewdrug檢驗(yàn)病因假設(shè)評(píng)價(jià)預(yù)防效果研究疾病的自然史新藥的上市后監(jiān)測(cè)目的Purpose23FraminghamstudyofcardiovasculardiseaseIndividuals30–62yearsoldincommunityatriskfordiseaseFramingham,MA,1948topresentExamplesofcohortstudy24GoaltoelucidatethenaturalhistoryofHIV/AIDS5000gaymen,volunteers5citiesinUS1984–Extensiveevaluations

QuestionnairePhysicalexaminationLaboratorytestingMulti-CenteredAIDSCohortStudy25類型

TypesBasedonrecruittimeofstudysubjects

Prospectivev.s.RetrospectiveBasedonthetypeofcohort

Fixedv.s.Dynamic依據(jù)研究對(duì)象召集的時(shí)間

前瞻性VS回顧性依據(jù)隊(duì)列的類型

固定VS動(dòng)態(tài)

26

類型

TypesCombinedwithcase-controlstudy

Nestedcase-controlstudyCase-cohortstudy與病例對(duì)照研究結(jié)合

巢式病例對(duì)照研究病例隊(duì)列研究

27

ProspectiveCohortstudyIdentifycohortconcurrentCategorybasedonexposurestatusorpossibleexplanatory/prognosticfactorsofsubjectinthepresent

隊(duì)列的確定是現(xiàn)在根據(jù)研究對(duì)象現(xiàn)在的暴露狀態(tài)或可能暴露/預(yù)后因素分組

依據(jù)研究對(duì)象召集的時(shí)間分類28Follow-upOutcomewilloccursometimeinfuture隨訪結(jié)局在將來某時(shí)刻出現(xiàn)

ProspectiveCohortstudy依據(jù)研究對(duì)象召集的時(shí)間分類29ProspectivecohortstudytimeExposureStudystartsDiseaseoccurrence依據(jù)研究對(duì)象召集的時(shí)間分類30ProspectiveCohort：QuestionQuestion:Arenon-steroidalanti-inflammatorydrugsariskfactorforGIbleeds?問題:

非甾體固醇抗炎藥是否為胃腸道出血的危險(xiǎn)因素?依據(jù)研究對(duì)象召集的時(shí)間分類31Identifycohort:

newdiagnosesofrheumatoidarthritisOct.2002toOct.2003Determineexposurestatus:

identifypatientsprescribedNSAID’sandthosewhoarenot確定隊(duì)列:

2002.10-2003.10診斷的類風(fēng)濕關(guān)節(jié)炎患者確定暴露狀態(tài):

確定開與未開NSAID’s藥物處方的病人ProspectiveCohort：Question依據(jù)研究對(duì)象召集的時(shí)間分類32Determineoutcomes:

follow-upallpatientsfor1year–identifyhowmanyGIbleedsthereareineachsub-cohortorexposuregroup確定結(jié)局:

隨訪所有的病人1年---確定在暴露及非暴露組出現(xiàn)多少胃腸道出血的病人。ProspectiveCohort：Question依據(jù)研究對(duì)象召集的時(shí)間分類33ProspectiveCohortStudiesAdvantageStrengthenstemporalityininferencecausemoreaccurately

measuringrisk

factors(notneedto

reconstructpastexposures)moreaccurately

measuring

confounding優(yōu)點(diǎn)

因果推斷的時(shí)間順序強(qiáng)危險(xiǎn)因素測(cè)量更準(zhǔn)確

(不需要構(gòu)建過去的暴露)更準(zhǔn)確的測(cè)量混雜因素依據(jù)研究對(duì)象召集的時(shí)間分類34Limitation:expensiveandtimeconsuming(inceptionandfollow-up)largenumbersrequiredtostudyrareoutcomesdifficulttostudychronicdiseaseswithlonglatency局限性:昂貴,費(fèi)時(shí)間(啟動(dòng)及隨訪)研究罕見結(jié)局是需大樣本難于研究慢性潛伏期長(zhǎng)的疾病ProspectiveCohortStudies35Historical(Retrospective)CohortStudyIdentifycohortinthepastE.g.,throughrecordsoradministrativedatabasesDetermineexposureorprognosticfactorsinthepastAgain,recordsordatabasesIdentifyoutcomeOutcomecanbeidentifiedinpastorpresentOutcomemustbeafterprevioustwosteps36RetrospectivecohortstudytimeExposureStudystartsDiseaseoccurrence37HistoricalCohortExampleQuestion:

Arenon-steroidalanti-inflammatorydrugsariskfactorforGIbleeds?問題:

非甾體固醇抗炎藥是否為胃腸道出血的危險(xiǎn)因素?38HistoricalCohortExampleIdentifycohort–e.g.,peoplediagnosedwithrheumatoidarthritisbetweenJanuaryandDecember1992Determineexposurestatus.WhichofthesepatientswereprescribedNSAID’s?Determineoutcome.Didpatientdevelopgastrointestinaltractbleedsduringthefiveyearsafterinceptionintocohort?(follow-uplasteduntilDecember1997)39Historical(Retrospective)CohortStudies

Advantage:Cohorteasiertoassemble

(inceptionperiodinpast)

Baselinemeasurements

alreadyavailable

Follow-upalready

takenplace

Lesscostlyandtime-

consuming優(yōu)點(diǎn):隊(duì)列易召集(在過去起始)基線測(cè)量已經(jīng)可以利用已經(jīng)隨訪耗費(fèi)少,省時(shí)間40Limitation:nowaytocontrolthequalityofpastmeasurementsincompletedatasetsconfoundermaybeincompletelycontrol局限性無法控制過去暴露的質(zhì)量資料不全混雜因素控制不全Historical(Retrospective)CohortStudies41

雙向性隊(duì)列研究

Mixed(Ambispective)CohortStudy研究隊(duì)列的確定是過去

Identifycohortinthepast根據(jù)研究對(duì)象過去某時(shí)刻的暴露情況分組

Categorythesubjectstogroupsbasedonexposuresituationinthepast需要隨訪needfollowup部分結(jié)局可能已出現(xiàn)

Someoutcomemayhavealreadyoccurred

第一節(jié)概述42MixedCohortExampleQuestion:Arenon-steroidalanti-inflammatorydrugsariskfactorforGIbleeds?Identifycohort(patientswhowerediagnosedwithrheumatoidarthritisbetweenOctober2000andSeptember2001)WhichofthesepatientsareprescribedNSAID’s?HowmanyofthesepatientswillexperienceGIbleedsduringnextfiveyears?

43時(shí)間順序

過去

現(xiàn)在

將來

歷史性隊(duì)列雙向性隊(duì)列前瞻性隊(duì)列回顧性收集已有的歷史資料繼續(xù)前瞻性收集資料前瞻性收集資料依據(jù)研究對(duì)象召集的時(shí)間分類44timeExposureStudystartsDiseaseoccurrenceDiseaseoccurrencetimeStudystartsExposuretimeDiseaseoccurrenceStudystarts歷史性隊(duì)列雙向性隊(duì)列前瞻性隊(duì)列Exposure依據(jù)研究對(duì)象召集的時(shí)間分類45前瞻性隊(duì)列研究

明確的檢驗(yàn)假設(shè)所研究疾病的發(fā)生率較高,一般不低于5‰明確規(guī)定暴露因素和結(jié)局變量可靠的測(cè)量手段足夠的觀察人群和暴露情況能完成隨訪的人群足夠的人、財(cái)、物力不同類型研究選用的原則

46CohortStudyDesignTypesFixedCohortAgroupofindividualsrecruitedandenrolledatauniformpointorinaperiodCohortdoesnottakeonnewmembersafteritisassembledExamplesPatientsadmittedtotheERwithacuteMISurvivorsofHiroshimabombingsChildrenborntoHIV-infectedmothers依據(jù)隊(duì)列的類型47歷史性隊(duì)列研究

前瞻性隊(duì)列研究1-5足夠數(shù)量、完整、有關(guān)研究對(duì)象暴露和結(jié)局檔案材料不同類型研究選用的原則

雙向性隊(duì)列研究

歷史性隊(duì)列條件繼續(xù)隨訪需前瞻性隊(duì)列研究條件48固定隊(duì)列fixedcohort研究開始start研究結(jié)束end出現(xiàn)結(jié)局outcomeoccurred未出現(xiàn)結(jié)局Withoutoutcome依據(jù)隊(duì)列的類型49TypesDynamiccohortAgroupofindividualsrecruitedandenrolledthroughamechanismthatallowsforinandoutmigrationofpeopleDynamicpopulationExamplesFraminghamStudyKaiserPermanente50動(dòng)態(tài)隊(duì)列DynamicCohort第一節(jié)概述出現(xiàn)結(jié)局Outcomeoccurred失訪Lostfollow-up依據(jù)隊(duì)列的類型研究開始start研究結(jié)束end51二硫化碳長(zhǎng)期低劑量的暴露與冠心病的關(guān)系

第二節(jié)研究實(shí)例52二硫化碳（CS2）神經(jīng)系統(tǒng)毒物，抑制酶的活性，影響脂蛋白代謝，造成心血管疾病長(zhǎng)期接觸低濃度CS2可引起慢性中毒和動(dòng)脈粥樣硬化短時(shí)間接觸高濃度的CS2蒸氣可急性中毒53研究因素

長(zhǎng)期低劑量的CS2暴露定義

在有CS2暴露但不至引起急性中毒的車間工作>5年20世紀(jì)60年代芬蘭職業(yè)衛(wèi)生研究所Hernberg和Tolonen教授做的前瞻性隊(duì)列研究54二、確定研究結(jié)局

心肌梗死血壓變化心電圖的改變心絞痛發(fā)作55三、確定研究現(xiàn)場(chǎng)和人群

暴露組

1942—1967年某粘纖廠25至64歲，343名男性工人有5年以上CS2暴露史對(duì)照組

年齡±3歲出生地區(qū)相同工種的體力消耗相當(dāng)在同一城市的造紙廠隨機(jī)選擇的343名男性工人

56四、資料收集

查閱檔案記錄

用藥情況、既往車間CS2的濃度等詢問

姓名、性別、年齡、工種及工作年限、吸煙、業(yè)余時(shí)間的體力活動(dòng)情況實(shí)驗(yàn)室檢查

血糖、血脂、血清膽固醇水平、血壓、心電圖、心臟大小、體重及車間CS2濃度的動(dòng)態(tài)變化57五、資料分析表4-1暴露組和對(duì)照組的心肌梗死發(fā)生率及RRCS2暴露組發(fā)生心肌梗死的RR為3.57，兩組致死性心肌梗死發(fā)生率和總的心肌梗死發(fā)生率差異有顯著性58

CS2在不同臨床類型冠心病的發(fā)生中作用程度不同臨床類型RRAR心肌梗塞3.575.25致死性心肌梗塞4.693.21非致死性心肌梗塞2.742.04心絞痛1.8911.6心電圖冠心樣改變1.46.1表4-2CS2與不同臨床類型冠心病的RR和AR比較59六、結(jié)論

長(zhǎng)期低劑量CS2暴露與冠心病發(fā)病和死亡存在因果關(guān)系CS2所致的冠心病，以致死性心肌梗死為主措施芬蘭當(dāng)局已于1972年把CS2的車間最高容許濃度從20ppm降至10ppm60PurposeIdentifyexposuresIdefineoutcomesIdentifystudyfieldandpopulationSamplesizeDatacollectioanandfollow-upQualitycontrol

明確目的確定研究因素確定研究結(jié)局確定研究現(xiàn)場(chǎng)與人群確定樣本量資料的收集與隨訪質(zhì)量控制第三節(jié)設(shè)計(jì)和實(shí)施

DesignandImplement61明確目的

ClarifyPurpose

在現(xiàn)況調(diào)查或病例對(duì)照研究的基礎(chǔ)上，提出可疑的暴露于疾病的關(guān)系

Basedontheresultsofdescriptivestudyandcase-controlstudy，togeneratehypothesisoftheassociationbetweensuspectedexposureanddisease62確定研究因素IdentifyExposureMainexposuresBasedonpurposeaccordingtodescriptivestudyandcase-controlstudy

Factormayeffectoutcome

confounder,demographyfeatures

主要暴露因素在描述性研究和病例對(duì)照研究的基礎(chǔ)上，根據(jù)研究目的確定可能影響結(jié)局的因素混雜因素人口學(xué)特征等63暴露測(cè)量

MeasuringExposureContent-Natureoftheexposure;biologicmechanismsQualityPeriodic-e.g.,cigarettes,sexualcontactsSingular-e.g.,nuclearexposureQuantityContinuousandperiodicexposuresmustbequantifiedDose-responserelationship64

暴露測(cè)量

MeasuringExposureMethodsofMeasuringInterviewMedicalexamBloodtestsorotherspecimens,Biomarkers,OtherlaboratorytestsRecords,medicalrecordsSamplestorageEnvironmentsurveillancedata65

MeasuringExposureMeasuringexposureisoneofthefundamentalactivitiesofacohortstudyExposuremeasurementmustbecomparableforallmembersofthecohortCarefullydefinedinadvanceofstudySpecificattentionshouldbegiventotheaccuracyandprecisionofproposedmeasurements-Pilotstudiesoftenneeded66

確定研究結(jié)局

DetermineOutcome發(fā)病或死亡血清指標(biāo)分子標(biāo)志的變化定性或定量MorbidityormortalityIndicatorofserumChangeofmolecularbiomarkerQuantityorquality結(jié)局是研究隊(duì)列中預(yù)期結(jié)果事件

outcomeareexpectedeventoffollow-up

67ExamplesofOutcomesorDiseasesLungCancerHeartDiseaseMotorvehicleinjuryHIVinfectionDiabetesDiphtheria68

一次研究可有多個(gè)結(jié)局Onestudymayhaveseveraloutcome吸煙吸煙smoking

慢性支氣管炎Chronicbronchitis冠心病CHD肺癌lungcancer結(jié)局的測(cè)量采用國(guó)際或國(guó)內(nèi)通用的標(biāo)準(zhǔn)Usingexistedinternationalornationstandard69研究現(xiàn)場(chǎng)

studyfield

有足夠符合條件的研究對(duì)象

Thereareenoughsuitablesubjects

領(lǐng)導(dǎo)重視、群眾支持

Governmentpayattention，masssupport

確定研究現(xiàn)場(chǎng)與研究人群

IdentifyStudyFieldandPopulation第三節(jié)設(shè)計(jì)與實(shí)施70研究現(xiàn)場(chǎng)StudyField發(fā)病率較高

Highincidence醫(yī)療條件好，交通便利

Highmedicalfacility，transportation有代表性

Nicerepresentatives71

研究人群StudyPopulation

從目標(biāo)人群中抽出的具有代表性的人

Samplingtherepresentativesubjectsfromtargetpopulation

未患所研究疾病

Diseasefree

分為暴露人群和非暴露人群

Categoriesasexposedandnon-exposedpopulation

確定人群納入標(biāo)準(zhǔn)

DefinePopulationatriskusinginclusioncriteria第三節(jié)設(shè)計(jì)與實(shí)施72暴露人群選擇

SelectionofExposedPopulationSpecialoccupationalexposuregroup(uraniumminersorasbestosworkers.Cooperation,goodrecord,regu.Exam,easyfollow-up)Specialexposuregroups(smokers,X-rayworkersThegeneralpopulation(theoutcomeofinteresthasahighincidencerate)73Specialresourcegroups(e.g.,physicians,nurses,insured)Geographicallyorfacility-definedgroups(hospitalswithspecializedmaternitycare)暴露人群選擇

SelectionofExposedPopulation74非暴露人群選擇

SelectionofNon-exposedGroup內(nèi)對(duì)照(internalcontrols)

一群研究對(duì)象內(nèi)部

Controlsisselectedwithaone-sample(population-based)cohortofexposure, Example:Selectthecohort(suchasallresidentsofagivenneighborhood)Allmembersofthecohortarethengivenfirstroundquestionnaires,and/orclinicalexaminations,and/ortestingtodetermineexposureThecohortisthendividedintoexposurecategoriesbasedonthoseresults第三節(jié)設(shè)計(jì)與實(shí)施75外對(duì)照(Externalcontrols)

一群研究對(duì)象外部Ifeveryoneinacohortisexposed(suchasworkersinanindustry),aseparatecohortassimilaraspossibletotheexposedintermsofincome,education,geography,andageshouldbesought非暴露人群選擇

SelectionofNon-exposedGroup76總?cè)丝趯?duì)照(totalpopulationcontrols)

整個(gè)地區(qū)現(xiàn)成的發(fā)病或死亡資料多重對(duì)照(multiplecontrols)

兩種或以上的對(duì)照形式非暴露人群選擇

SelectionofNon-exposedGroup77StudyPopulationsExamplesFraminghamstudyofcardiovasculardiseaseIndividuals30–62yearsoldincommunityatriskfordiseaseFramingham,MA,1948topresent78Table4-3FraminghamStudyCohortAssemblyNo.MenNo.WomenTotalRandomSample3,0743,4336,507Respondents2,0242,4454,469Volunteers312428740RespondentsfreeofCHD19752,4184,393VolunteersfreeofCHD307427734TotalfreeofCHD2,2822,8455,12779StudyPopulationsMACSMulti-CenteredAIDSCohortStudyGoaltoelucidatethenaturalhistoryofHIV/AIDS5000gaymen,volunteers5citiesinUS1984–1999ExtensiveevaluationsQuestionnairePhysicalexaminationLaboratorytestingRepository80

計(jì)算樣本量時(shí)需考慮的問題

Questionsshouldpayattentionto

抽樣方法

Samplingmethods

暴露組與非暴露組的比例

Oddsofexposedtounexposedgroups

失訪率

Proportionoflostfollowup

確定樣本量SampleSize第三節(jié)設(shè)計(jì)與實(shí)施81

p0IncidenceinexposedpopulationorgeneralpopulationP1-P0Thedifferenceofincidencebetweenexposedandcontrolpopulation

α

SignificantlevelPower1-

FactorsEffectedSampleSize82樣本大小估計(jì)EstimationofSampleSize

查表Table

公式計(jì)算（條件暴露組和對(duì)照組樣本含量相等）

formula(samplesizeequalbetweenexposedandcontrolgroupP1：暴露組預(yù)期發(fā)病率expectedincidenceinexposure

P0：對(duì)照組預(yù)期發(fā)病率expectedincidenceinnon-exposure

：兩個(gè)發(fā)病率的平均值averageof2incidence

83

例：擬用定群研究方法研究暴露于某種藥物與嬰兒先天性心臟病之間的聯(lián)系，假設(shè)已知非暴露組發(fā)病率為P0=0.008,P1=0.016,當(dāng)α=0.05β=0.1時(shí),估計(jì)需要的樣本量(Zα=1.96，Zβ=1.282)每組樣本量為3892人84

基線資料

baselinedata

隨訪

followup

資料收集

datacollection資料的收集與隨訪DataCollectioanandFollow-up第三節(jié)設(shè)計(jì)與實(shí)施85基線資料Base-lineData

暴露的資料dataofexposure

個(gè)體的其他信息otherinformationdemographyconfounder第三節(jié)設(shè)計(jì)與實(shí)施86

隨訪Follow-up

隨訪目的、對(duì)象、內(nèi)容和方法

Purpose，subjects,contentsandmethod

觀察終點(diǎn)

Endpoint

觀察終止時(shí)間

Endoffollowup

隨訪間隔

Intervalbetweenfollowup

隨訪者

Personscarriedoutfollowup第三節(jié)設(shè)計(jì)與實(shí)施87PurposeofFollowingup

Tracksubjectsinbothexposedandnon-exposedgroupDefineoutcomeeventsFurthercollectdatainexposuresandconfounding

SubjectsofFollowingup

Allsubjectsinbothexposedandnon-exposedgroups

88ContentofFollow–up

sametobase-linedata,payattentiontooutcomeFollow-upMethodsinterview,telephoneself-administratequestionnairephysicalexammedicalrecordsdataofsurveillance89觀察終點(diǎn)

EndPointStudysubjectsoccurredexpectedoutcome

suchasdisease,death,syndrome隨訪間隔IntervalBetweenFollowup

Dependsonthespeedofoutcome觀察終止時(shí)間EndofFollowupofTotalCohort

Dependontheincidence,latency,labor90Follow-upCompletenessandnon-participation90%ruleofthumbAllsubjectsmusthaveanequallikelihoodfordetectingtheoutcomeDiseaseascertainmentmustbecomparablebetweentheexposedandunexposedsubjectsNumberofvisitsReasonsforadditionalevaluations91調(diào)查員選擇調(diào)查員培訓(xùn)制定調(diào)查員手冊(cè)監(jiān)督SelectionofinvestigatorTrainingofinvestigatorFormulationbrochureforinvestigatorMonitor

質(zhì)量控制QualityInsurance第三節(jié)設(shè)計(jì)與實(shí)施92BasicmodelfordatasortingPersontimecalculateRatecalculateEffectestimation

第四節(jié)資料的整理和分析DataSortingandAnalysis資料的基本整理模式人時(shí)的計(jì)算率的計(jì)算效應(yīng)估計(jì)93一、資料的基本整理模式

BasicModelofDataSorting病例Case非病例Non-case合計(jì)Total暴露組Exposureaba+b=n1非暴露組Nonexposurecdc+d=n0合計(jì)a+c=m1b+d=m0a+b+c+d=t暴露組發(fā)病率=a/n1Incidenceofexposedgroup

非暴露組發(fā)病率=c/n0Incidenceofnon-exposed

表4-4隊(duì)列研究資料歸納整理表Table4-4Analysisofcohortstudy94二、人時(shí)的計(jì)算

CalculateforPerson-time

精確法近似法壽命表法ExactmethodApproximatemethodLifeexpectancymethod95精確法

ExactMethod：Table4-4Thecalculationofperson-yearsforthreesubjects（Terminationdateofobservationis1981.01.01）Cumulativeperson-years:11.15+12.06+10.92=34.13IncidenceDensity(mortality):1/34.13=29.3‰96Table4-5Thenumberofmalesurvivalineveryagegroupsandeveryyear近似法

ApproximateWhencalculatetheagespecificmortality………Thenumberofdeathsbelongtoeachagegroupwerecategorizedasnumerator,Theexposedpersonyearsineachagegroupwerecategorizedasdenominator.97壽命表法計(jì)算暴露人年

CalculationofexposedpersonyearswithLifeTableLx=lx+1/2(Nx－Dx－Wx)Lx:ExposedpersonyearswithinxtimeIx:TheobservednumberatthebeginningofxtimeNx:ThenumbersubjectsofenteredintothecohortwithinxtimeDx:Thenumberofend-pointwithinxtimeWx:Thenumberoflostwithinxtime98表4-7壽命表法計(jì)算人年實(shí)例

Table4-7

ExampleofthecalculationofpersonyearswithLifeTable99三、率的計(jì)算CalculateofRate累積發(fā)病率發(fā)病密度標(biāo)化死亡比標(biāo)化比例死亡比CumulativeincidenceIncidencedensityStandardizedmortalityratio,SMRStandardizedproportionalmortalityratio,SPMR100

變化范圍0-1range:0-1

適用條件樣本大suitablefor:largesample

人口穩(wěn)定stablepopulation

整齊的資料

evendata

必須注明時(shí)間長(zhǎng)短N(yùn)otethetimeperiod累積發(fā)病率

CumulativeIncidence,CI

CI=

觀察期內(nèi)發(fā)?。ɑ蛩劳觯㎞umberofnewcase(ordeath)

觀察開始時(shí)的人口數(shù)

Numberofpersonsenteringobservation

101

發(fā)病密度

IncidenceDensity

變化范圍0-∞r(nóng)ange:0-∞

適用條件觀察時(shí)間長(zhǎng)

Suitablefor:longobservation

人口不穩(wěn)定

Unstablepopulation

存在失訪

withlostfollowup

資料不很整齊

datanotevenID

=觀察期內(nèi)發(fā)?。ɑ蛩劳觯┤藬?shù)Numberofnew(death)cases觀察人時(shí)Observedpersontime102標(biāo)化死亡比

(StandardizedMortalityRatio,SMR)變化范圍0-∞r(nóng)ange：

0-∞

適用條件結(jié)局事件的發(fā)生率低

suitablefor：lowincidenceofoutcome

不宜直接計(jì)算率時(shí)

notsuitablecalculateratedirectly

SMR=研究人群觀察期內(nèi)發(fā)?。ɑ蛩劳觯┤藬?shù)Numberofnew(death)casesinstudiedpopulation標(biāo)準(zhǔn)人口預(yù)期發(fā)?。ɑ蛩劳觯┤藬?shù)Numberofexpected(death)casesinstandardpopulation

103全人口(標(biāo)準(zhǔn)人口）某病的發(fā)?。ㄋ劳觯┞省劣^察人口數(shù)Newcases(death)ofadiseaseintotalpopulationXNumberofobservedpersons預(yù)期發(fā)?。ㄋ劳觯?shù)的計(jì)算：ExpectedCases(Death)104SMR的意義

被研究人群發(fā)生（死于）某病的危險(xiǎn)性是標(biāo)準(zhǔn)人群的多少倍

Thetimesofriskofadisease(ordeath)instudypopulationoverstandardpopulationSMR=1

研究人群某病發(fā)?。ㄋ劳觯┪ｋU(xiǎn)=標(biāo)準(zhǔn)人群

IftheSMRisquotedasaratioandisequalto1.0,thenthismeansthenumberofobserveddeathsequalsthatofexpectedcases.

105SMR>1

研究人群病發(fā)病（死亡）危險(xiǎn)>標(biāo)準(zhǔn)人群，是標(biāo)準(zhǔn)人群的SMR倍

Ifhigherthan1.0,thenthereisahighernumberofdeathsthanisexpected,istheSMRtimesofstandardpopulation

SMR<1

研究人群某病發(fā)?。ㄋ劳觯┪ｋU(xiǎn)<標(biāo)準(zhǔn)人群

Thereisalowernumberofdeathsthanisexpected106標(biāo)化比例死亡比

（StandardizedProportionalMortalityRatio,SPMR）

變化范圍0~∞

適用條件不能得到歷年人口資料僅有死亡人數(shù)、原因、日期和年齡

SPMR=ActuallydeathNo.ExpecteddeathNo.Range0~∞Suitablefor:noyearlypopulationdata,onlythereisdeathNo.,cause,dateandageofdeath

107

預(yù)期死亡數(shù)計(jì)算（No.of

ExpectedDeath）：全人口中某病因死亡數(shù)全部死亡數(shù)×某單位實(shí)際全部死亡數(shù)Deathduetoadisease

TotalNo.ofDeath

×ActuallydeathNo.insomedepartment108率的顯著性檢驗(yàn)

TestforSignificance

U檢驗(yàn)

Utest

直接概率法

Probablenumbermethod

二項(xiàng)分布檢驗(yàn)

Binomialdistribution

泊松分布檢驗(yàn)

Poissondistribution

2檢驗(yàn)

2test

計(jì)分檢驗(yàn)

Scoretest

109

四、效應(yīng)的估計(jì)

TheEstimationofEffectRelativeRisk(RR)AttributableRisk(AR)ARPercent(AR%)PopulationAR(PAR)PARPercent(PAR%)Doseresponserelationship

相對(duì)危險(xiǎn)度歸因危險(xiǎn)度歸因危險(xiǎn)度百分比人群歸因危險(xiǎn)度人群歸因危險(xiǎn)度百分比劑量反應(yīng)關(guān)系110相對(duì)危險(xiǎn)度（RelativeRisk,RR）暴露組率Rateinexposed非暴露組率Rateinnonexposed111

意義Implication暴露組的發(fā)病或死亡的危險(xiǎn)是非暴露組的多少倍

Thetimesoftheprobabilityofthediseaseordeathoccurringintheexposedgroupversusanon-exposedgroup.RR值暴露的效應(yīng)：暴露與結(jié)局關(guān)聯(lián)強(qiáng)度

RReffectofexposed：theassociationbetweenexposureandoutcome112表4-8吸煙者與非吸煙者死于不同疾病的RRRRofdeathfromdifferentdiseasesinsmokerandnonsmoker

Cardiovasculardisease1.7296.7510.7170.32LungcancerDisease50.12Smoker4.69Non-smoker

RR（1/10萬(wàn)人年）113意義Implication

吸煙者因肺癌死亡的危險(xiǎn)是非吸煙者的10.7倍

Smokerswouldbe10.7timesaslikelyasnon-smokerstodieoflungcancer吸煙者因心血管疾病死亡的危險(xiǎn)是非吸煙者的1.7Smokerswouldbe1.7timesaslikelyasnon-smokerstodevelopcardiovasculardisease114

表4-9RR與關(guān)聯(lián)強(qiáng)度

RRandstrengthenofassociation

很強(qiáng)Verystrengthen10~＜0.1

強(qiáng)Strengthen3.0~9.90.1~0.3

中Middle

1.5~2.90.4~0.6弱Weak

1.2~1.40.7~0.8

無Noassociation1.0~1.10.9~1.0關(guān)聯(lián)強(qiáng)度RRStrengthenofassociation115RR的95%CI

RR95%CI

反自然對(duì)數(shù)即為RR的95%CI

Theanti-logarithmofln

isCI95%ofRRWoolf法()dcbaRRVar1111+++=ln()RRVarRRln96.1±lnln116歸因危險(xiǎn)度

(AttributableRisk,AR)

意義ImplicationE與ē人群比較，所增加的疾病發(fā)生數(shù)量

TheincreasedNo.ofdiseasescomparinganexposedpopulationandanunexposedpopulation

AR值暴露因素消除后所減少的疾病數(shù)量

Eliminatingtheexposure,thereducedNo.ofdiseasesca或()1000-=-×=RRIIIRRAR010nnIIARe-=-=117

意義RR吸煙對(duì)肺癌的病因?qū)W意義較大AR戒煙對(duì)心血管疾病的預(yù)防作用較大即公共衛(wèi)生意義較大

表4-10RR與AR的區(qū)別ThedifferencebetweenRRandARCardiovasculardiseaseLungcancerDisease1.710.7RR126.43170.32296.7545.434.6950.12ARNon-smoker

Smoker（1/10萬(wàn)人年）

ImplicationRRsmokinghaslargeretiologysignificanceofonlungcancerARstopsmokinghashigherpreventablesignificanceoncardiovasculardiseases,i.e.thepublichealthsignificance118歸因危險(xiǎn)度百分比AR%

（病因分值

EtiologicFractionEF）意義Implication:

暴露人群中的發(fā)病或死亡歸因于暴露的部分占全部發(fā)病或死亡的百分比

Theproportionofthecasesthattheexposurehadplayedacausalroleinitsdevelopment.

RR

或-%100%0×=eIIIeAR%1001%×-=RRAR119人群歸因危險(xiǎn)度

(PopulationAttributableRisk,PAR)

意義暴露人群與一般人群比較，所增加的疾病發(fā)生率的大小

Theincreaseddiseaseintheexposedcomparingwithgeneralpopulation

PAR值暴露因素消除后所減少的疾病數(shù)量

PARthereductioninincidenceaftereliminatetheexposure

PAR=It－I0

It：總?cè)巳郝?/p>

rateintotalpopulationIo：非暴露組率

rateinNon-exposedpopulation

120人群歸因危險(xiǎn)度百分比PAR%

意義Implication

PAR占總?cè)巳喝堪l(fā)?。ɑ蛩劳觯┑陌俜直?/p>

TheproportionofPARincasesor(death)intotalpopulation

或

Pe：總?cè)巳旱谋┞侗壤?/p>

proportionofexposedintotalpopulation121劑量反應(yīng)關(guān)系

DoseResponseRelationship分析方法列出不同暴露水平下的發(fā)病率以最低暴露水平組為對(duì)照，計(jì)算各暴露水平的RR和危險(xiǎn)度差(RD)必要時(shí)，應(yīng)對(duì)率的變化作率的趨勢(shì)性檢驗(yàn)

Analysismethod

ListtheincidenceofdifferentexposedlevelsCalculatetheRRandARofdifferentexposedlevelsusingthelowestasreferenceCarriedouttendencytestifnecessary

122

結(jié)果血清膽固醇水平患冠心病的RR說明存在劑量效應(yīng)關(guān)系表4-1140-59歲男子按初始血清膽固醇分組冠心病6年發(fā)生情況

血清膽固醇(mmol/L)

人數(shù)

病例數(shù)

危險(xiǎn)度

平均年發(fā)病率

RR