第1題Whatistheultimategoalofepidemiology?ATodeterminethe

extentofdisease

foundinthecommunity.BTostudythe

naturalhistoryandprognosisofdisease.CToidentifythe

causeofadiseaseanditsrelevantriskfactors.DToimprovethecontrolofdiseaseandwillenhancethequalityoflifeofthosewhohavedevelopedseriousillness.第2題ThefirststepfortheepidemiologistproceedtoidentifythecauseofadiseaseistoATrytoderiveappropriateinferencesaboutapossiblecausalrelationshipfromthepatternsoftheassociationsthathavebeenpreviouslyfound.BFindmorepatientswiththedisease.CDeterminewhetheranassociationexistsbetweenexposuretoafactororacharacteristicofapersonandthepresenceofthediseaseinquestion.DProvideappropriatetherapytopatients.第3題WhichofthefollowingstatementsisWRONGabouttherelationshipbetweenepidemiologyandclinicalpractice?AThepracticeofmedicineisdependentonpopulationdata.BThepracticeofmedicineisdependentonphysician’sexperiences.CThediagnosisisbasedoncorrelationoftheclinicalfindingswiththefindingsofsurgicalpathologyorautopsyandwiththeresultsofstudiesinalargegroupofpatients.DSelectionofappropriatetherapyisalsopopulationbased.第4題Althoughitisextremelyimportantforustomaximizeourknowledgeofthebiologyandpathogenesisofdisease,itisnotalwaysnecessarytoknoweverydetailofthepossiblepathogenicmechanismstopreventdisease.第5題Whichofthefollowingstatementsistrueaboutthehigh-riskapproachtoprevention?AIttargetsahigh-riskgroupwiththepreventivemeasureBIthastobeabletocorrectlyidentifyindividualswiththedisease.CApreventivemeasureiswidelyappliedtoanentirepopulation.DItoftenrequireaclinicalactiontoidentifythehigh-riskgrouptobetargeted.正確答案：ABD第6題WhichofthefollowingstatementsisWRONGaboutthepopulation-basedapproachtoprevention?AIttargetsahigh-riskgroupwiththepreventivemeasureBApreventivemeasureiswidelyappliedtoanentirepopulation.CItmustberelativelyinexpensiveandnoninvasive.DItisapublichealthapproaches第7題Tertiarypreventionisanactionto

preventcomplicationsinthosewhohavealreadydevelopedsignsandsymptomsofanillnessandhavebeendiagnosed.第8題Secondarypreventionisanactiontakentopreventthedevelopmentofadiseaseinapersonwhoiswellanddoesnot(yet)havethediseaseinquestion.第9題Primarypreventionisanactiontoidentifypeopleinwhomadiseaseprocesshasalreadybegunbutwhohavenotyetdevelopedclinicalsignsandsymptoms.第10題Amajoruseofepidemiologicevidenceistoidentifysubgroupswhoareathighriskfordisease.第11題Whataretheobjectivesofepidemiology?ATodeterminethe

extentofdisease

foundinthecommunity.BTostudythe

naturalhistoryandprognosisofdisease.CToidentifythecauseofadiseaseanditsrelevantriskfactors.DToevaluatepreventiveandtherapeuticmeasuresandmodesofhealthcaredelivery.正確答案：ABCD第1題The

secondaryattackrate

istheattackrateinsusceptiblepeoplewhowerenotexposedtothesuspectedagentwhohavebeenexposedtoaprimarycase.第2題Apersonwhoacquiresthediseasefromanotherpersoniscalleda

secondarycase.第3題Apersonwhoacquiresthediseasefromthatexposure(e.g.,fromacontaminatedfood)iscalleda

secondarycase.第4題Theincubationperiodforinfectiousdiseaseshasitsanalogueinnoninfectiousdiseases,whichisoftenreferredtoasthelatencyperiod.第5題Herdimmunity

istheresistanceofapersontoadisease.第6題Theamountofdiseaseinapopulationdependsonabalancebetweenthenumberofpeoplewhoaresusceptibleandthenumberofpeoplewhoarenot.第7題Inadiseaseoutbreak,theepidemiologicpicturethatismanifesteddependsonwhethertheexposureissingle,multiple,orcontinuous.第8題Pandemicisaworldwideepidemic.第9題InanEpidemic,theoccurrenceofillnessesofsimilarnatureclearlyinexcessofnormalexpectancy.第10題Diseasescanonlybetransmitted

directly.第11題WhichofthefollowingisaboutLatentdisease？ADiseasethatisnotyetclinicallyapparentbutisdestinedtoprogresstoclinicaldisease.BDiseasethatisnotclinicallyapparentandisnotdestinedtobecomeclinicallyapparent.CApersonfailsto“shakeoff”theinfection,anditpersistsforyears,attimesforlife.DAninfectionwithnoactivemultiplicationoftheagent.Onlythegeneticmessageispresentinthehost.第12題WhichofthefollowingisaboutPersistent(chronic)disease？ADiseasethatisnotyetclinicallyapparentbutisdestinedtoprogresstoclinicaldisease.BDiseasethatisnotclinicallyapparentandisnotdestinedtobecomeclinicallyapparent.CApersonfailsto“shakeoff”theinfection,anditpersistsforyears,attimesforlife.DAninfectionwithnoactivemultiplicationoftheagent.Onlythegeneticmessageispresentinthehost.第13題WhichofthefollowingisaboutSubclinicaldisease？ADiseasethatisnotyetclinicallyapparentbutisdestinedtoprogresstoclinicaldisease.BDiseasethatisnotclinicallyapparentandisnotdestinedtobecomeclinicallyapparent.CApersonfailsto“shakeoff”theinfection,anditpersistsforyears,attimesforlife.D.Aninfectionwithnoactivemultiplicationoftheagent.Onlythegeneticmessageispresentinthehost.DAninfectionwithnoactivemultiplicationoftheagent.Onlythegeneticmessageispresentinthehost.第14題Whenadiseaseappearstohaveoccurredatmorethananendemic(usual)levelandwewishtoinvestigateitsoccurrence,whatdoweneedtofind?AWho

wasattackedbythedisease?BWhen

didthediseaseoccur?CWhere

didthecasesarise?DA,B,andC第15題WhichofthefollowingisaboutPreclinicaldisease？ADiseasethatisnotyetclinicallyapparentbutisdestinedtoprogresstoclinicaldisease.BDiseasethatisnotclinicallyapparentandisnotdestinedtobecomeclinicallyapparent.CApersonfailsto“shakeoff”theinfection,anditpersistsforyears,attimesforlife.DAninfectionwithnoactivemultiplicationoftheagent.Onlythegeneticmessageispresentinthehost.第16題WhichofthefollowingstatementsisWRONGaboutincubationperiod?AA.ItistheintervalfromreceiptofinfectiontothetimeofillnessbeingcuredBB.ItreflectsthetimeneededfortheorganismtoreplicatesufficientlyCC.ItrelatestothesiteinthebodyatwhichtheorganismreplicatesDD.Itmaybeinfluencedbythedoseoftheinfectiousagentreceivedatthetimeofinfection第17題Threecriticalvariablesininvestigatinganoutbreakorepidemicareasfollows:AWhendidtheexposuretakeplace?BWhendidthediseasebegin?CWhatwastheincubationperiodforthedisease?DHowmanypersonswerewithpreclinicaldisease?正確答案：ABC第18題Forherdimmunitytoexist,thefollowingconditionsmustbemetAThereareenoughsusceptiblepersonsinthecommunityBThediseaseagentmustberestrictedtoasinglehostspecieswithinwhichtransmissionoccursCThattransmissionmustberelativelydirectfromonememberofthehostspeciestoanotherDInfectionsmustinducesolidimmunity正確答案：BCD第19題ThepotentialofagivenorganismforspreadingandproducingoutbreaksdependsonAItsrateofgrowthBTheroutebywhichitistransmittedfromonepersontoanotherCThenumberofsusceptiblepersonsinthecommunityDThenumberofpersonsinthecommunity正確答案：ABC第20題ThefactorsthatcancausehumandiseaseusuallyincludeAbiologicfactorsBphysicalfactorsCchemicalfactorsDnutritionalfactors正確答案：ABCD第21題HumandiseaseusuallyresultsfromaninteractionofAthehostBtheagentCthewaterDtheenvironment正確答案：ABD第三章課后作業(yè)第1題DiseaseXhasadurationof15yearsandalowincidence(5per100,000person-years).DiseaseYhasadurationof5yearsandalowincidence(5per100,000person-years).ComparingDiseaseXtoYinthesamepopulation,wewouldexpectDiseaseXtohavea:ABettercurerateBLowerprevalenceCHigherprevalenceDHigherincidence第2題Incidenceratesaremostusefulforidentifyingriskfactorsandimplementingpreventivemeasuresforadisease.第3題Whencalculatingincidencerates,thechoiceofthedenominatorshouldincludeonlyindividualswhohaveneverhadthediseaseinquestion.第4題Prevalenceratesaremoreusefulthanincidenceratesforunderstandingthecurrentneedforhealthcareservicesinapopulation.第5題Passivesurveillanceinpublichealthreferstotheactivegatheringofdatabyhealthofficials,typicallythroughdirectcontactwithpatientsorhealthcareproviders.第6題Diseasesurveillanceisakeyactivityinpublichealththatinvolvestheongoingandsystematiccollection,analysis,andinterpretationofhealthdata.第7題Ahigherincidencerateofadiseasealwaysleadstoahigherprevalencerate.第8題Pointprevalencereferstothenumberofnewcasesofadiseasethatoccurinapopulationwithinaspecifiedperiod.第9題Theattackrateforthefluinaschoolcanbedeterminedsolelybycountingthenumberofstudentswhoreportedsickoneday.第10題Theincidencerateofadiseasecanbeincreasedbyimprovingtheaccuracyofdiseasediagnosisandreportingwithinahealthcaresystem.第11題Iftheincidencerateofadiseaseisdeclining,itindicatesthattheeffectivenessofpreventivemeasureshasimproved.第12題Inthecontextofdiseasesurveillance,whichofthefollowingactivitiesarecriticalcomponentsoftheprocess?ACollectingdataonthenumberofnewcasesofadiseaseinapopulation.BEstimatingtheproportionofthepopulationalreadyimmunetothedisease.CConductinganalysistoidentifypotentialoutbreaksortrends.DReportinginformationtohealthauthoritiesforpromptaction.正確答案：ACD第13題Considerapopulationof10,000individuals.Overthecourseofoneyear,therewere250newcasesofaparticulardisease.Thepopulationsizeremainedconstantthroughouttheyear.Tocalculatetheincidencerateforthisdisease,whichofthefollowingformulaswouldyouuse?AIncidenceRate=(NumberofNewCases/TotalPopulation)*100BIncidenceRate=(NumberofNewCases/At-RiskPopulation)*100C(NumberofNewCases/TotalPopulationatRisk)*TimePeriodD(NumberofNewCases/Person-TimeatRisk)*TimePeriod正確答案：BD第14題Whichofthefollowingstatementsaccuratelycompareincidenceratesandprevalencerates?AIncidenceratesmeasurethenumberofnewcasesinapopulationoveraspecificperiodoftime,whileprevalenceratesmeasurethetotalnumberofcasesatagivenpointintimeoroveraspecifiedperiod.BPrevalenceratesarehigherthanincidenceratesbecausetheyincludeexistingcases.CIncidenceratescanbeusedtoestimatetheriskofdevelopingadiseaseovertime,whereasprevalenceratesprovideinformationonthecurrentburdenofdisease.DBothincidenceratesandprevalenceratescanbeexpressedasproportionsorpercentages,butonlyincidenceratesconsiderthetimefactor.正確答案：ACD第15題Whichofthefollowingstatementsaboutprevalencerateistrue?APrevalencerateisalwayshigherthanincidencerateinchronicdiseases.BPrevalenceratecanbeaffectedbythedurationofthedisease.CTheprevalenceratecanbeusedtomeasuretheburdenofadiseaseinapopulation.DPrevalencerateistheproportionofpeoplewhohaveadiseaseatagivenpointintimeoroveraparticularperiod.正確答案：BCD第16題Whichofthefollowingstatementsaboutincidenceratesarecorrect?ATheincidenceratecanbecalculatedbydividingthetotalnumberofpeoplewhoalreadyhaveadiseaseatthestartofastudybythepopulationatrisk.BAhigherincidencerateindicatesthatadiseaseismorelikelytooccurinagivenpopulationwithinaparticulartimeframe.CIncidenceratescouldbeexpressedasthenumberofcasesper1,000personsperyear.DTheincidencerateforadiseaseisunaffectedbythedurationofthestudyperiod.正確答案：BC第17題Whichofthefollowingstatementsaccuratelydescribestheterm"attackrate"inepidemiology?ATheattackratereferstotheproportionofapopulationthatisimmunetoadisease.BTheattackrateisthesameastheprevalencerate,measuringthetotalnumberofcasesinapopulationatagiventime.CTheattackrateisequivalenttotheincidencerate,countingnewcasesoveraperioddividedbythepopulationatrisk.DTheattackrateisusedspecificallyforoutbreaksandreferstotheproportionofnewcasesinadefinedpopulationduringaparticulartimeintervalafterexposure.第18題Whatisthedifferencebetweenincidencerateandprevalencerate?AIncidencerateisusedforchronicdiseases,whereasprevalencerateisusedforacuteconditions.BPrevalenceratemeasurestheseverityofadisease,whileincidenceratemeasuresthenumberofdeathsfromadisease.CIncidenceratemeasuresthenumberofnewcasesinapopulationovertime,whileprevalenceratemeasuresthetotalnumberofcasesinapopulationataspecificpointintimeoroveraperiod.DPrevalencerateisalwayshigherthanincidenceratebecauseitcountsallexistingcases,includingthosethathaverecovered.第19題ChikungunyavirusinfectionwasrecentlyintroducedintotheDominicanRepublic.Duringthefirstyearafterintroduction,thevirushasinfectedatotalof251,880peopleintheDominicanRepublic,whichhasapopulationsizeof10.4millionpeople.Infectionbythechikungunyavirusisrarelyfatal.Whichofthefollowingiscorrect?ATheprevalenceofchikungunyainfectionsis251,880BThe1-yearcumulativeincidenceofchikungunyais24.2per1,000personsCTheincidenceofchikungunyainfectionis251,880peryearDThecumulativesurvivalfromchikungunyainfectionsis24.2per1,000persons第20題ThefollowinghealthstatisticsareavailableontheInternetforcountryZabouttwodiseaseoutcomes.DiseaseAhasanannualincidenceof225per100,000populationandanannualmortalityrateof150per100,000.DiseaseBhasanannualincidenceof500per100,000populationandthesameannualmortalityrateasdiseaseA.NeitherdiseaseAorBhasacure.WhatwouldyouconcluderegardingtheburdenofthesediseasesincountryZ?ATheproportionatemortalityishigherfordiseaseAthandiseaseBBThecasefatalityratioishigherfordiseaseBthandiseaseACDiseaseAhasahigherprevalencethandiseaseBDDiseaseBhasahigherprevalencethandiseaseA第21題AsurveywasconductedamongthenonhospitalizedadultpopulationoftheUnitedStatesduring2008through2011.Theresultsfromthissurveyareshownbelow.In18-29yearsgroup,thepersonswithhypertensionis4%.In30-39,is10%.In40-49,is22%.In50-59,is43%.In60-69,is54%.Andin70andolderagegroup,is64%.Theresearchersstatedthattherewasanage-relatedincreaseintheriskofhypertensioninthispopulation.Youconcludethattheresearchers’interpretation:AIsincorrectbecauseprevalenceisusedBIsincorrectbecauseitwasnotbasedonratesCIsincorrectbecausethecalculationsarenotage-adjustedDIsincorrectbecauseitwasnotbasedonratesIscorrect第22題Whatwouldbetheeffectonage-specificincidenceratesofuterinecancerifwomenwithhysterectomieswereexcludedfromthedenominatorofthecalculations,assumingthattherearesomewomenineachagegroupwhohavehadhysterectomies?ATherateswouldtendtodecreaseBTherateswouldtendtoincreaseCTherateswouldincreaseinoldergroupsanddecreaseinyoungergroupsDItcannotbedeterminedwhethertherateswouldincreaseordecrease第23題Whichofthefollowingisanadvantageofactivesurveillance?ARequireslessprojectstaffBMoreaccurateduetoreducedreportingburdenforhealthcareprovidersCReportingsystemscanbedevelopedquicklyDReliesondifferentdiseasedefinitionstoaccountforallcases第24題AprevalencesurveyconductedfromJanuary1throughDecember31,2022,identified1,000casesofschizophreniainacityof2millionpersons.Theincidencerateofschizophreniainthispopulationis5/100,000personseachyear.Whatpercentageofthe1,000caseswerenewlydiagnosedin2022?A1%B50%C5/100000D10%第25題AtaninitialexaminationinCityA,migraineheadachewasfoundin5of1,000menaged30to35yearsandin10of1,000womenaged30to35years.Theinferencethatwomenhaveatwotimesgreaterriskofdevelopingmigraineheadachethandomeninthisagegroupis:ACorrectBIncorrect,becausearatiohasbeenusedtocomparemaleandfemaleratesCIncorrect,becauseoffailuretodistinguishbetweenincidenceandprevalenceDIncorrect,becausenodataforacomparisonorcontrolgrouparegiven第四章課后作業(yè)第1題In1990,therewere4,500deathsduetolungdiseasesinminersaged20to64years.Theexpectednumberofdeathsinthisoccupationalgroup,basedonage-specificdeathratesfromlungdiseasesinallmalesaged20to64years,was1,800during1990.So,thestandardizedmortalityratio(SMR)forlungdiseasesinminerswas2.5.第2題Inamortalityrate,thedenominatorrepresentstheentirepopulationatriskofdyingfromthedisease,includingboththosewhohavethediseaseandthosewhodonothavethedisease,butwhoareatriskofdevelopingthedisease.第3題Itshowsthenumberofcancerdeathsisincreasingfrom2000to2020inacountry.So,theriskofdyingfromcancerisincreasing,too.第4題Themortalityratecannotbeaffectedbyimprovementsinhealthcareorchangesinlifestyle.第5題Selectionofastandardpopulationissomewhatarbitrarywhenperformingstandariazation.第6題Theadjustedratesdonotreflectthetruemortalityriskofa“real”population.第7題Bycause-specificmortality,suicideisrankedseventh,butbyPYLL,itrankedfourthinacountry.Thisreflectsthefactthatalargeproportionofsuicide-relateddeathsoccurinoldpersons.第8題WhenlookingatreportsthatusePYLL,itisimportanttonotewhatassumptionstheauthorhasmade,includingwhatlifeexpectancyatbirthhasbeenselected.第9題Ifall-causemortalityratesdiffer,cause-specificmortalityratescandiffersignificantly,evenwhentheproportionatemortalityisthesame.第10題Case-fatalityrateindicatestheprobabilityofdeathofadiagnoseddisease,soitcanreflecttheseverityofthediseaseandthelevelofdiagnosisandtreatmentofmedicalcare.第11題WhatarethepurposesofcalculatingPotentialYearsofLifeLost(PYLL)?AToidentifytheagegroupswiththehighestmortalityrates.BTomeasuretheburdenofdiseaseintermsofworkingyearslost.CToevaluatetheeffectivenessofhealthinterventionprograms.DTocomparetheoverallhealthstatusbetweendifferentregionsorpopulations.正確答案：ABCD第12題Whichofthefollowingstatementsregardingtheusesofmortalityratesarecorrect?AMortalityratesareusedtomeasuretheoveralllevelofhealthinapopulation.BTheycanbeemployedtocomparethehealthandsurvivaloutcomesbetweendifferentregionsorpopulations.CMortalityratesareaffectedbyfactorssuchasagedistributionwithinthepopulation.DPolicymakersusetheseratestoallocateresourcesforhealthcare,publichealthinterventions,andtosethealth-relatedgoals.正確答案：ABCD第13題Whichofthefollowingstatementsregardingdirectstandardizationarecorrect?ADirectstandardizationinvolvesadjustingratesorstatisticsbyapplyingthemtoastandardpopulation,whichmeanstheyareweightedbasedonthisstandard.BDirectstandardizationiscommonlyusedtocomputedemographic-specificratessuchasage-standardizedmortalityrates.CDirectstandardizationdoesnotaccountfordifferencesinpopulationstructurewhencomparinggroupsortimeperiods.DTheresultofdirectstandardizationisaratethatrepresentswhattheratewouldbeifthepopulationhadthesamestructureasthechosenstandardpopulation.正確答案：ABD第14題Whichofthefollowingstatementsregardingexpectationoflifearecorrect?ALifeexpectancyatbirthiscalculatedbyaveragingtheagesatwhichpeopledieoveragivenperiod.BLifeexpectancyistypicallyhigherincountrieswithbetterhealthcaresystemsandlowerratesofdisease.CExpectationoflifeisunaffectedbyfactorssuchaslifestylechoices,genetics,oraccesstomedicalcare.DThelifeexpectancyatacertainagereflectstheaveragenumberofadditionalyearsthatpeoplewhohavealreadyreachedthatageareexpectedtolive.正確答案：ABD第15題Amortalityrateisagoodreflectionoftheincidencerateundertwoconditions:Athecase-fatalityrateishighBthecase-fatalityrateislowCthedurationofdiseaseisshortDthedurationofdiseaseislong正確答案：AC第16題Acityreportsatotalof200deathsinagivenyear.Outofthese,40deathswereduetocardiovasculardiseases,50deathswereduetocancer,andtheremainingdeathswereduetoothercauses.Whatistheproportionatemortalityattributabletocardiovasculardiseases?A0.2B0.1C0.25D0.33第17題Whatisthepurposeofthestandardizationapproachindataanalysis?AToincreasethevariabilityofthedataandidentifyoutliers.BTotransformdataintoacommonscaletofacilitatecomparisonandaggregation.CToreducethedimensionalityofthedatasetbycreatingcompositevariables.DToassigncategoricallabelstocontinuousvariablesforeaseofinterpretation.第18題WhichofthefollowingstatementsbestdescribestheconceptofPotentialYearsofLifeLost(PYLL)?APYLLisametricusedtocalculatetheoveralllifeexpectancyofapopulation.BPYLLisamethodforassessingthequalityoflifeofindividualswithinasociety.CPYLLisanindicatorthatmeasurestheeconomicimpactofdiseasesonacountry'sworkforce.DPYLLisameasurethatfocusesonthenumberofyearslostduetoprematuremortality,regardlessofthecauseofdeath.第19題Whichofthefollowingstatementsbestdescribesthecasefatalityrate?AItmeasuresthelikelihoodofdyingfromadiseaseforallpeoplewhocontractit.BItindicatestheproportionofpatientsalreadydiagnosedwithadiseasewhoeventuallydiefromit.CItprovidesinformationontheoverallmortalityrateinapopulation.DItisusedtoassesstheeffectivenessoftreatmentsforaparticulardisease.第20題Aprogrammanagerfromaninternationalhealthfundingagencyneedstoidentifyregionsthatwouldbenefitfromaninterventionaimedatreducingprematuredisability.Theprogrammanagerasksahealthcareconsultanttodevelopaproposalusinganindexthatwouldhelphermakethisdecision.Whichofthefollowingwouldbestservethispurpose?ACase-fatalityBCrudemortalityrateCDisability-adjustedlife-yearsDStandardizedmortalityratio第21題Foradiseasesuchaspancreaticcancer,whichishighlyfatalandofshortduration:AIncidenceratesandmortalityrateswillbesimilarBMortalityrateswillbemuchhigherthanincidenceratesCIncidencerateswillbemuchhigherthanmortalityratesDNoneoftheaboveiscorrect第22題Theincidencerateofadiseaseisfivetimesgreaterinwomenthaninmen,buttheprevalenceratesshownosexdifference.Thebestexplanationisthat:AThecrudeall-causemortalityrateisgreaterinwomenBThecase-fatalityfromthisdiseaseisgreaterinwomenCThecase-fatalityfromthisdiseaseislowerinwomenDRiskfactorsforthediseasearemorecommoninwomen第23題ThemortalityratefromdiseaseXincityAis75/100,000inpersons65to69yearsold.ThemortalityratefromthesamediseaseincityBis150/100,000inpersons65to69yearsold.TheinferencethatdiseaseXistwotimesmoreprevalentinpersons65to69yearsoldincityBthanitisinpersons65to69yearsoldincityAis:ACorrectBIncorrect,becauseoffailuretoadjustfordifferencesinagedistributionsCIncorrect,becauseoffailuretodistinguishbetweenprevalenceandmortalityDIncorrect,becauseaproportionisusedwhenarateisrequiredtosupporttheinference第24題Age-adjusteddeathratesareusedto:ACorrectdeathratesforerrorsinthestatementofageBDeterminetheactualnumberofdeathsthatoccurredinspecificagegroupsinapopulationCComparedeathsinpersonsofthesameagegroupDEliminatetheeffectsofdifferencesintheagedistributionsofpopulationsincomparingdeathrates第25題Inacountrywithapopulationof6millionpeople,60,000deathsoccurredduringtheyearendingDecember31,2020.Theseincluded30,000deathsfromcholerain100,000peoplewhoweresickwithcholera.Whatwasthecause-specificmortalityratefromcholerain2020?A0.5B0.3C0.05D0.1第五章課后作業(yè)第1題Thereliabilityoftheexperimentishigh,thevalidityishigh.第2題Thepositivepredictivevalueisgreatlyinfluencedbytheprevalencerate.第3題Thenetsensitivityoftwoseriestestswillbeincreased.第4題Thenetspecificityoftwoseriestestswillbeincreased.第5題Thefinalspecificityoftwoparalleltestswillbeincreased.第6題Thefinalsensitivityoftwoparalleltestswillbeincreased.第7題Positivepredictivevalueandsensitivityarethesame.第8題Thedifferencebetween1andsensitivityisthefalsenegativerate.第9題Thecorrectindexisthesumofsensitivityandspecificityandminus1.第10題Thesumofthefalse-positiverateandsensitivityis1.第11題Whichofthefollowingstatementsaboutpositivepredictivevaluearecorrect?AThepositivepredictivevalueislargelyinfluencedbydiseaseprevalence.BhespecificityandsensitivityofthetesthavenoeffectonthepositivepredictivevalueCThesensitivityofthetesthaslittleeffectonthepositivepredictivevalueDThespecificityofthetesthasagreatinfluenceonthepositivepredictivevalue正確答案：ACD第12題Whichofthefollowingsabouttheresultsoftwoscreeningtestsinseries(two-stage)arecorrect?AthefinalsensitivitywillbeincreasedBthefinalspecificitywillbeincreasedCthefinalspecificitywillbereducedDthesensitivityandspecificitywereunchanged正確答案：BD第13題In100DMpatient,80arepositivebyusingabloodsugartest,andin200non-DMpatients,180arenegativebythistest.Whichofthefollowingsarecorrect?Athesensitivityofthistestis80%Bthespecificityofthisis90%Cthefalsenegativerateofthistestis10%Dthefalsepositiverateofthistestis10%正確答案：ABD第14題Inthefollowingsentencesabouttheresultofparalleltests,whicharecorrect?AitwillincreasefinalsensitivityBitwillincreasefinalspecificityCitwilldecreasefinalsensitivityDitwilldecreasefinalspecificity正確答案：AD第15題Inonehospital,someoneusedXraytoscreenbreastcancer,90arepositivein100breastcancerpatients,whileonly10arepositivein100controlswithoutbreastcancer.So,thosewiththeirresultsbeing90%areAsensitivityBspecificityCpositivepredictivevalueDYouden