NRnj511njDifferentialnjDiagnosisnjandnjPrimarynjCare-
nj Midnj Termnj Review
1.whatnjisnjthenjsensitivitynjofnjthenjProstatenjSpecificnjAntigennj(PSA)njfornjdetecti
ngnjprostatenjcancer?:nj#njmennjwithnjprostatenjcancer
#njmennjwithnjpositivenjPS
Anj160
#njmennjwithnjnegativenjP
SAnj40
tot
alnj2
00
Thenjcorrectnjanswernjisnj160/200.njSensitivitynjisnjthenjproportionnjofnjpatientsn
withnjthenjdiseasenjthatnjhavenjanjpositivenjresult;njitnjisnjthenjnumbernjofnjtruenjpo
sitivesnjdividednjbynjthenjtotalnjnumbernjofnjpatientsnjwhonjhavenjthenjdisease.
2.Anjdiagnosticnjtestnjisnjusednjinnjanjsamplenjofnj1000njpatients.nj500njofnjthesenjpatie
ntsnjhavenjthenjdisease,njwhilenj500njdonjnot.njOfnjthosenj500njpatientsnjwithoutnjthenjd
isease,nj30njtestnjpositive,njandnj470njtestnjnegative.njWhatnjisnjthenjspecificitynjofnjthe
njtest?:njThenjcorrectnjanswernjisnj470/500.
Specificitynjisnjthenjproportionnjofnjpatientsnjwhonjtestnjnegativenjoutnjofnjthenjt
otalnjnumbernjofnjpatientsnjwhonjdonjnotnjhavenjthenjdisease;njitnjisnjthenjnumbe
rnjofnjtruenjnegativesnjoverallnjnegatives.njInnjthisnjexample,nj500/1000njpatie
ntsnjhavenjthenjdisease.njOfnjthosenj500njpatientsnjwithoutnjthenjdisease,nj30njt
estnjpositive,njandnj470njtestnjnegative.
3.ThenjPositivenjPredictivenjValuenj(PPV)njofnjanjtestnjrefersnjtonjwhichnjofnjthenjfoll
ow-
njing?:njthenjproportionnjofnjpatients njwithnjanjpositivenjtestnjwhonjhavenjthenjdi
sease.
4.Whichnjofnjthenjfollowingnjdependsnjonnjthenjprevalencenjofnjthenjdisease?:njposi
tivenjpredictivenjvalue.
Predictivenjvaluesnjdependnjonnjthenjprevalencenjofnjdiseasenjinnjthenjpopulati
onnjwhereasnjsensitivitynjandnjspecificitynjarenjintrinsicnjpropertiesnjofnjthenjte
st.njReliabilitynjrefersnjtonjthenjconsistencynjornjstabilitynjofnjanjmeasure.
5.Anjlownjpretestnjprobabilitynjofnjdiseasenjmaynjleadnjtonjwhichnjofnjthenjfollowing?:nj
lownjpositivenjpredictivenjvaluenjandnjmorenjfalse-positivenjresults.
Positivenjpredictivenjvaluenjincreasesnjwithnjprevalence;njtherefore,njanjlownjpr
1nj/
nj48
, NRnj511njDifferentialnjDiagnosisnjandnjPrimarynjCare-
nj Midnj Termnj Review
evalencenjvaluenjyieldsnjanjlownjpositivenjpredictivenjvaluenjandnjimpliesnjanjhig
hnjfalse-
positivenjrate.njNegativenjpredictivenjvaluenjdecreasesnjwithnjprevalence,njand
njsensitivitynjandnjspecificity njdonjnotnjvarynjwithnjprevalence.
2nj/
nj48
, NRnj511njDifferentialnjDiagnosisnjandnjPrimarynjCare-
nj Midnj Termnj Review
6.Ifnjyounjstronglynjsuspectnjthatnjanjpatientnjisnjpositivenjfornjanjspecificnjconditionnj
butnjtestsnjnegative,njthenjnegativenjresultnjmaynjbe::njfalse-
negativenjtestnjresultsnjduenjtonjanjlownjnegativenjpredictivenjvalue.
Atnjthenjindividualnjlevel,njyournjclinicalnjsuspicionnjisnjequivalentnjtonjpre-
testnjprobabilitynjandnjhighnjprevalencenjatnjthenjpopulationnjlevel.njNegativenjp
redictivenjvaluenjisnjinverselynjcorrelatednjwithnjprevalence;njtherefore,njyournj
clinicalnjsuspicionnjtranslatesnjtonjanjlownjnegativenjpredictivenjvalue,njsuggest
ingnjanjfalse-negativenjtestnjresult.
7.Whichnjtest(s)njprovidenjdatanjrelevantnjtonjthenjchiefnjcomplaint:njFever:njCBC
ChecknjCBCnjwithnjdifferentialnjfornjneutrophilnjshiftnjinnjsuspectednjinfection
8.Whichnjtest(s)njprovidenjdatanjrelevantnjtonjthenjchiefnjcomplaint:njUnexplain
ednjbruising:njCBC
Checknjplateletnjcount
9.Whichnjtest(s)njprovidenjdatanjrelevantnjtonjthenjchiefnjcomplaint:njFatigue:njBothnj
CBCnjandnjCMP
ChecknjRBC,njHgbnjandnjHctnjfornjanemia,njCMPnjfornjpotentialnjlivernjornjkidneynjab
ormalities
10.Whichnjtest(s)njprovidenjdatanjrelevantnjtonjthenjchiefnjcomplaint:njCardiacnjd
ys-njrhythmias:njCMP
Monitornjelectrolytesnjfornjabnormalities
11.Whichnjtest(s)njprovidenjdatanjrelevantnjtonjthenjchiefnjcomplaint:njUnexplain
ednjweightnjloss:njBothnjCBCnjandnjCMP
ChecknjWBCnjfornjinflammationnjornjpossiblenjcancer,njCMPnjfornjglucose,njlivernj
ornjkidneynjabnormalities
12.Whichnjtest(s)njprovidenjdatanjrelevantnjtonjthenjchiefnjcomplaint:njEdema:njCMP
Checknjfornjkidneynjfunction
13.WhatnjisnjSNAPPS?:njSummarizenjthenjhistorynjandnjfi
ndingsnjNarrownjthenjdifferentialnjdiagnosisnjtonjtwonjornjt
hreenjpossibilities
Analyzenjthenjdifferentialnjbynjcomparingnjandnjcontrastingnjthenjp
ossibilitiesnjProbenjthenjpreceptornjbynjaskingnjquestionsnjaboutnjal ornjuncertai
ternativenjapproachesnjties n-
3nj/
nj48
, NRnj511njDifferentialnjDiagnosisnjandnjPrimarynjCare-
nj Midnj Termnj Review
Plannjthenjmanagementnjofnjthenjclient'snjhealthnjiss
uesnjSelectnjannjissuenjfromnjthenjcasenjfornjself-
directednjlearning
4nj/
nj48
nj Midnj Termnj Review
1.whatnjisnjthenjsensitivitynjofnjthenjProstatenjSpecificnjAntigennj(PSA)njfornjdetecti
ngnjprostatenjcancer?:nj#njmennjwithnjprostatenjcancer
#njmennjwithnjpositivenjPS
Anj160
#njmennjwithnjnegativenjP
SAnj40
tot
alnj2
00
Thenjcorrectnjanswernjisnj160/200.njSensitivitynjisnjthenjproportionnjofnjpatientsn
withnjthenjdiseasenjthatnjhavenjanjpositivenjresult;njitnjisnjthenjnumbernjofnjtruenjpo
sitivesnjdividednjbynjthenjtotalnjnumbernjofnjpatientsnjwhonjhavenjthenjdisease.
2.Anjdiagnosticnjtestnjisnjusednjinnjanjsamplenjofnj1000njpatients.nj500njofnjthesenjpatie
ntsnjhavenjthenjdisease,njwhilenj500njdonjnot.njOfnjthosenj500njpatientsnjwithoutnjthenjd
isease,nj30njtestnjpositive,njandnj470njtestnjnegative.njWhatnjisnjthenjspecificitynjofnjthe
njtest?:njThenjcorrectnjanswernjisnj470/500.
Specificitynjisnjthenjproportionnjofnjpatientsnjwhonjtestnjnegativenjoutnjofnjthenjt
otalnjnumbernjofnjpatientsnjwhonjdonjnotnjhavenjthenjdisease;njitnjisnjthenjnumbe
rnjofnjtruenjnegativesnjoverallnjnegatives.njInnjthisnjexample,nj500/1000njpatie
ntsnjhavenjthenjdisease.njOfnjthosenj500njpatientsnjwithoutnjthenjdisease,nj30njt
estnjpositive,njandnj470njtestnjnegative.
3.ThenjPositivenjPredictivenjValuenj(PPV)njofnjanjtestnjrefersnjtonjwhichnjofnjthenjfoll
ow-
njing?:njthenjproportionnjofnjpatients njwithnjanjpositivenjtestnjwhonjhavenjthenjdi
sease.
4.Whichnjofnjthenjfollowingnjdependsnjonnjthenjprevalencenjofnjthenjdisease?:njposi
tivenjpredictivenjvalue.
Predictivenjvaluesnjdependnjonnjthenjprevalencenjofnjdiseasenjinnjthenjpopulati
onnjwhereasnjsensitivitynjandnjspecificitynjarenjintrinsicnjpropertiesnjofnjthenjte
st.njReliabilitynjrefersnjtonjthenjconsistencynjornjstabilitynjofnjanjmeasure.
5.Anjlownjpretestnjprobabilitynjofnjdiseasenjmaynjleadnjtonjwhichnjofnjthenjfollowing?:nj
lownjpositivenjpredictivenjvaluenjandnjmorenjfalse-positivenjresults.
Positivenjpredictivenjvaluenjincreasesnjwithnjprevalence;njtherefore,njanjlownjpr
1nj/
nj48
, NRnj511njDifferentialnjDiagnosisnjandnjPrimarynjCare-
nj Midnj Termnj Review
evalencenjvaluenjyieldsnjanjlownjpositivenjpredictivenjvaluenjandnjimpliesnjanjhig
hnjfalse-
positivenjrate.njNegativenjpredictivenjvaluenjdecreasesnjwithnjprevalence,njand
njsensitivitynjandnjspecificity njdonjnotnjvarynjwithnjprevalence.
2nj/
nj48
, NRnj511njDifferentialnjDiagnosisnjandnjPrimarynjCare-
nj Midnj Termnj Review
6.Ifnjyounjstronglynjsuspectnjthatnjanjpatientnjisnjpositivenjfornjanjspecificnjconditionnj
butnjtestsnjnegative,njthenjnegativenjresultnjmaynjbe::njfalse-
negativenjtestnjresultsnjduenjtonjanjlownjnegativenjpredictivenjvalue.
Atnjthenjindividualnjlevel,njyournjclinicalnjsuspicionnjisnjequivalentnjtonjpre-
testnjprobabilitynjandnjhighnjprevalencenjatnjthenjpopulationnjlevel.njNegativenjp
redictivenjvaluenjisnjinverselynjcorrelatednjwithnjprevalence;njtherefore,njyournj
clinicalnjsuspicionnjtranslatesnjtonjanjlownjnegativenjpredictivenjvalue,njsuggest
ingnjanjfalse-negativenjtestnjresult.
7.Whichnjtest(s)njprovidenjdatanjrelevantnjtonjthenjchiefnjcomplaint:njFever:njCBC
ChecknjCBCnjwithnjdifferentialnjfornjneutrophilnjshiftnjinnjsuspectednjinfection
8.Whichnjtest(s)njprovidenjdatanjrelevantnjtonjthenjchiefnjcomplaint:njUnexplain
ednjbruising:njCBC
Checknjplateletnjcount
9.Whichnjtest(s)njprovidenjdatanjrelevantnjtonjthenjchiefnjcomplaint:njFatigue:njBothnj
CBCnjandnjCMP
ChecknjRBC,njHgbnjandnjHctnjfornjanemia,njCMPnjfornjpotentialnjlivernjornjkidneynjab
ormalities
10.Whichnjtest(s)njprovidenjdatanjrelevantnjtonjthenjchiefnjcomplaint:njCardiacnjd
ys-njrhythmias:njCMP
Monitornjelectrolytesnjfornjabnormalities
11.Whichnjtest(s)njprovidenjdatanjrelevantnjtonjthenjchiefnjcomplaint:njUnexplain
ednjweightnjloss:njBothnjCBCnjandnjCMP
ChecknjWBCnjfornjinflammationnjornjpossiblenjcancer,njCMPnjfornjglucose,njlivernj
ornjkidneynjabnormalities
12.Whichnjtest(s)njprovidenjdatanjrelevantnjtonjthenjchiefnjcomplaint:njEdema:njCMP
Checknjfornjkidneynjfunction
13.WhatnjisnjSNAPPS?:njSummarizenjthenjhistorynjandnjfi
ndingsnjNarrownjthenjdifferentialnjdiagnosisnjtonjtwonjornjt
hreenjpossibilities
Analyzenjthenjdifferentialnjbynjcomparingnjandnjcontrastingnjthenjp
ossibilitiesnjProbenjthenjpreceptornjbynjaskingnjquestionsnjaboutnjal ornjuncertai
ternativenjapproachesnjties n-
3nj/
nj48
, NRnj511njDifferentialnjDiagnosisnjandnjPrimarynjCare-
nj Midnj Termnj Review
Plannjthenjmanagementnjofnjthenjclient'snjhealthnjiss
uesnjSelectnjannjissuenjfromnjthenjcasenjfornjself-
directednjlearning
4nj/
nj48
