Content Validity: Types, Definition , Example

Content validity

2. Types of Validity
1.Criterion-relatedValidity
2.ConstructValidity
3.ContentorCurricularValidity

3. Content Validity
Contentvalidityreferstotheconnections
betweenthetestitemsandthesubject-
relatedtasks.

4. Content Validity
Psychometricsareoftheviewthatcontent
validityrequiresbothitemvalidityand
samplingvalidity.

5. Content Validity
Psychometricsareoftheviewthatcontentvalidityrequiresboth
itemvalidityandsamplingvalidity.
•Itemvalidityisconcernedwithwhetherthetest
itemsrepresentmeasurementintheintended
contentarea.
•Samplingvalidity(sometimescalled
logicalvalidity)ishowwellthetestcoversallof
theareasyouwantittocover.

6. Content Validity
Thetechniquesthatarecommonlyused
fordefiningtheintendedcontentofatest
istheestablishmentofatableof
specifications

7. Content Validity
TableofSpecifications(TOS)
isatoolusedtoensurethatatestorassessment
measuresthecontentandthinkingskillsthatthetest
intendstomeasure.Thus,whenusedappropriately,it
canprovideresponsecontentandconstruct(i.e.,
responseprocess)validityevidence.

8. Content Validity
TableofSpecifications(TOS)
ThepurposeofaTableofSpecificationsistoidentify
theachievementdomainsbeingmeasuredandto
ensurethatafairandrepresentativesampleof
questionsappearonthetest.

9. Content Validity
TableofSpecifications(TOS)
ATableofSpecificationsallowstheteacherto
constructatestwhichfocusesonthekeyareasand
weightsthosedifferentareasbasedontheir
importance.
Example

10. Content Validity
Contentvalidityisexaminedbytwoways:
•Byexpert'sjudgement,and
•Bystatisticalanalysis(ensureallitemsmeasure
thesamethings)

11. Content Validity
Step-by-stepguide:Howtomeasurecontent
validity
•Step1:Collectdatafromexperts
•Step2:Calculatethecontentvalidityratio
•Step3:Calculatethecontentvalidityindex

12. Content Validity
Step-by-stepguide:Howtomeasurecontent
validity
•Step1:Collectdatafromexperts
Measuringcontentvalidityrequiresinput
fromajudgingpanelofsubjectmatterexperts
(SMEs).SMEsarepeoplewhoareinthebest
positiontoevaluatethecontentofatest.

13. Content Validity
Step-by-stepguide:Howtomeasurecontent
validity
•Step1:Collectdatafromexperts
Foreachindividualquestion,thepanelmustassess
whetherthecomponentmeasuredbythequestionis
“essential,”“useful,butnotessential,”or“not
necessary”formeasuringtheconstruct.

14. Content Validity
Step-by-stepguide:Howtomeasurecontent
validity
•Step2:CalculatetheContentValidityRatio(CVR)
formulatocalculatetheCVRforeachquestion:
??????????????????=
??????
??????−
??????
2
??????
2
where:
??????
??????=numberofSMEpanelists
indicating“essential”
??????=totalnumberofSMEpanelists

15. Example: Calculating the content validity ratio
Supposeyouaskapaneloffiveexpertstoevaluateadiagnostictest
consistingofsevenquestions.Thefirstquestionwasrated
as“essential”byfourexperts.
Thecontentvalidityratioforthefirstquestionwouldbecalculatedas:
??????????????????=
??????
??????−
??????
2
??????
2
=
4−
5
2
5
2
=0.6
Usingthesameformula,youcalculatetheCVRforeachquestion.

17. Example: Calculating the content validity ratio
Notethatthisformulayieldsvalues
whichrangefrom+1to−1.Values
above0indicatethatatleasthalfthe
SMEsagreethatthequestionis
essential.Thecloserto+1,thehigher
thecontentvalidity.

18. Example: Calculating the content validity ratio
Inorderto
rulethatout,
youcanuse
thiscritical
valuestable.
Dependingonthe
numberofexperts
inthepanel,
thecontentvalidity
ratio(CVR)fora
given question
shouldnotfall
belowaminimum
value,alsocalled
thecriticalvalue.

19. Content Validity
Step-by-stepguide:Howtomeasurecontent
validity
•Step3:Calculatethecontentvalidityindex
Tomeasurethecontentvalidityoftheentiretest,you
needtocalculatethecontentvalidityindex(CVI).TheCVIis
theaverageCVRscoreofallquestionsinthetest.
Rememberthatvaluescloserto1denotehighercontent
validity.

20. Content Validity
Step-by-stepguide:Howtomeasurecontent
validity
•Step3:Calculatethecontentvalidityindex
Tocalculatethecontentvalidityindex(CVI)
oftheentiretest,youtaketheaverageofallthe
CVRscoresofthesevenquestions.

21. Content Validity
Step-by-stepguide:Howtomeasurecontent
validity
•Step3:Calculatethecontentvalidityindex
Here,thatwouldbe:??????????????????=
0.6+0.2−0.2+0.2−0.2+0.6+1
7
=0.31
ComparingtheCVIwiththecriticalvalueforapanelof5experts(0.99),
younoticethattheCVIistoolow.Thismeansthatthetestdoesnot
accuratelymeasurewhatyouintendeditto.