Turkish validity and reliability of Eustachian tube dysfunction questionnaire-7

www.bjorl.org

Brazilian

Journal

of

OTORHINOLARYNGOLOGY

ORIGINAL

ARTICLE

Turkish

validity

and

reliability

of

Eustachian

tube

dysfunction

questionnaire-7

夽

Erdo˘

gan

Özgür

_,

_Cem

_Bilgen

_,

_Beyhan

_Cengiz

_Özyurt

b_{EgeUniversity,DepartmentofOtorhinolaryngology,Izmir,Turkey} c_{CelalBayarUniversity,DepartmentofPublicHealth,Manisa,Turkey}

Received10January2017;accepted1May2017 Availableonline31May2017

KEYWORDS Eustachiantube; Reliabilityand validity; Validationstudies Abstract

Introduction:Duringclinicalevaluations,inordertointerpretpatients’complaintscausedby Eustachiantubedysfunctionandtomonitorthesuccessofthetreatment,standardized and disease-relatedscalesarenecessary.

Objective: TheaimofthisstudywastoinvestigatethevalidityandreliabilityoftheTurkish versionofEustachiantubedysfunctionquestionnaire-7.

Methods:Fortypatients diagnosedwithEustachiantubedysfunctionand40healthy individ-ualswereenrolledforthestudy.AfterlanguagevalidationoftheEustachiantubedysfunction questionnaire-7for Turkish,ascalewascompletedby thebothEustachiantubedysfunction andcontrolgroups.Twoweeksafterthefirstevaluation,15ofthecasesfilledoutthescale againwithoutanytreatmentintervention.Known-groupsmethodwasusedinvalidityanalysis. Floor-ceilingeffect,test---retestmethod,item-totalscorecorrelationandinternalconsistency analysiswereusedinreliabilityanalyses.

Results:Cronbach’salphacoefficientwas0.714fortheentirequestionnaire.Thetest---retest reliability coefficient for the total scale was determined as 0.792, indicating correlation betweenthetwoquestionnairescompletedbythesamepatientovertime.IntheEustachian tubedysfunctiongroup,totalandeachitemscores werefoundsignificantlyhigherthanthe controlgroup(p<0.001).

Conclusion: TheTurkishversionofEustachiantubedysfunctionquestionnaire-7wasfound to behighlyvalidandreliable.ThisscaleisrecommendedtouseforscreeningofEustachiantube dysfunctionandevaluatingtreatmentoutcome.

© 2017 Associac¸˜ao Brasileira de Otorrinolaringologia e Cirurgia C´ervico-Facial. Published by Elsevier Editora Ltda. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).

夽 _{Pleasecitethisarticleas:ÖzgürE,BilgenC,CengizÖzyurtB.TurkishvalidityandreliabilityofEustachiantubedysfunction}

questionnaire-7.BrazJOtorhinolaryngol.2018;84:435---40.

∗_{Correspondingauthor.}

E-mail:[email protected](E.Özgür).

PeerReviewundertheresponsibilityofAssociac¸ãoBrasileiradeOtorrinolaringologiaeCirurgiaCérvico-Facial.

https://doi.org/10.1016/j.bjorl.2017.05.001

1808-8694/©2017Associac¸˜aoBrasileiradeOtorrinolaringologiaeCirurgiaC´ervico-Facial.PublishedbyElsevierEditoraLtda.Thisisanopen accessarticleundertheCCBYlicense(http://creativecommons.org/licenses/by/4.0/).

PALAVRAS-CHAVE

Tubaauditiva; Confiabilidadee validade;

Estudosdevalidac¸ão

ValidadeeconfiabilidadedoEustachiantubedysfunctionquestionnaire-7noidioma

turco

Resumo

Introduc¸ão:No intuito de interpretar as queixas dos pacientescausadas por disfunc¸ões na tubaauditivaduranteumaavaliac¸ãoclínica,epara monitorarosucesso dotratamento,há necessidadedeescalaspadronizadasrelacionadasàdoenc¸a.

Objetivo:InvestigaravalidadeeaconfiabilidadedaversãoturcadoEustachiantube dysfunc-tionquestionnaire-7.

Método: Quarenta pacientes diagnosticados com disfunc¸ão da tuba auditiva e 40 indiví-duossaudáveis foramincluídos noestudo.Apósavalidac¸ãodo Eustachiantubedysfunction questionnaire-7paraoidiomaturco,oquestionáriofoiaplicadaaosgruposdisfunc¸ãodatuba auditivaecontrole.Duassemanasapósaprimeiraavaliac¸ão,15pacientespreencheramo ques-tionárionovamentesemqualquertratamento.Ométododegruposconhecidosfoiutilizadona análisedevalidade.Osefeitostetoechão,ométodoteste-reteste,acorrelac¸ãoseescorede item-totaleaanálisedeconsistênciainternaforamutilizadosnasanálisesdeconfiabilidade. Resultados: Ocoeficientealfa deCronbach foide 0,714 para todooquestionário. O coefi-cientedeconfiabilidadeteste-retesteparaaescalatotalfoideterminadocomo0,792,indicando correlac¸ãoentreosdoisquestionáriospreenchidospelomesmopacienteaolongodotempo. Nogrupodisfunc¸õesdatubaauditiva,foiobservadoqueosescorestotaledecadaitemforam significativamentemaioresdoquenogrupocontrole(p<0,001).

Conclusão:AversãonoidiomaturcodoEustachiantubedysfunctionquestionnaire-7foi con-sideradaaltamenteválidaeconfiável.Recomenda-seautilizac¸ãodessaescalaparaatriagem dedisfunc¸õesdatubaauditivaeavaliac¸ãodoresultadodotratamento.

© 2017 Associac¸˜ao Brasileira de Otorrinolaringologia e Cirurgia C´ervico-Facial. Publicado por Elsevier Editora Ltda. Este ´e um artigo Open Access sob uma licenc¸a CC BY (http:// creativecommons.org/licenses/by/4.0/).

Introduction

Beyondjustbeingatubethatlinkstwoanatomicspaces,the Eustachiantube possessescrucialfunctions forthemiddle earcavityassuchasventilating,regulatingitspressureand protection.1_{OncethesefunctionsaredisruptedEustachian} tubedysfunction(ETD)occurs.Thisconditioniscommonin otorhinolaryngologypractice.2_{Inthebeginning,ETDcauses} complaintssuchasmildauralfullness.However,asthe situ-ationgetsmoreobstinateitmayinducetympanicmembrane retractions, adhesions, recurrent otitis media with effu-sion andeven chronic otitis media.Hence, diagnosis and treatment for chronic ETD is critically important.3 _During clinical applications, in order tointerpret patients’ com-plaints caused by ETD and to monitor the success of the treatment,itisrequiredtohavestandardizedand disease-related scales. For this purpose, McCoul et al. published ‘Eustachiantube dysfunctionquestionnaire-7(ETDQ-7)’ as avalidandreliablemethodforclinical applications.4 _This scalehasbeenusedtoassesstheeffectivenessofthe treat-mentaswellasdeterminingtheseverityofdisease.5---7_The aimofthisstudywastoinvestigatethevalidityand reliabil-ityoftheTurkishversionofETDQ-7.

Methods

This study was designed as a validation study.This study wasinaccordancewithDeclarationofHelsinkiandhasbeen approvedbytheLocalEthicsCommittee(20478486-348).All

participantswerefullyinformedaboutthestudyand writ-teninformedconsentformswereobtained.Tocarryoutthe validity and reliability of Turkish version of ETDQ-7, per-missionwasobtainedfromtheauthoroftheoriginalscale (Anand,V.).

Selectionofparticipants

Invalidityandreliabilitystudies,itissuggestedthatsample sizeisrequiredtobeatleast5---10foldmorethannumber ofitems.8,9

Selectionofthecasegroup

Atotalof40individuals(olderthan18yearsold)admitted tooutpatientclinicofotorhinolaryngologybetweenAugust 2015andDecember2015andwerediagnosedwithETDwere enrolledfortheETDgroup.Participantswhohadchronic dis-easeslikediabetesmellitus,hypertension,atherosclerosis, orwerediagnosedwithactiveupperrespiratoryinfection, tympanicmembraneperforation,hearinglossand/or tinni-tusinEar,NoseandThroat(ENT)examinationandfailedto fillETDQ-7formwereexcludedfromthestudy.

Selectionofthecontrolgroup

Forty healthy, age andsex-matched adults wereincluded asacontrolgroup.Itwasprovenwithmedicalexamination

Table1 Descriptivestatistics,item-totalscorecorrelationcoefficientsandinternalconsistencyresultsforETDgroup.

Scaleitems Mean

score±SD Ceiling effect(%) Flooreffect (%) Cronbachalphaif itemdeleted Totalscore correlationa_(r)

Pressureintheears(Item1) 4.3±1.7 5.0 17.5 0.688 0.567

Painintheears (Item2)

3.1±1.7 30.0 5.0 0.664 0.651

Afeelingthatyourearsare cloggedor‘‘under water’’(Item3)

4.9±1.8 7.5 27.5 0.695 0.547

Earsymptomswhenyou haveacoldorsinusitis (Item4)

4.2±2.3 25.0 25.0 0.702 0.605

Cracklingorpoppingsounds intheears(Item5)

4.1±1.7 10.0 10.0 0.674 0.616

Ringingintheear(Item6) 3.5_±2.0 22.5 10.0 0.712 0.503

Afeelingthatyourhearing ismuffled(Item7)

4.5±1.9 10.0 22.5 0.617 0.784

a _{Pearsoncorrelationtest,allcorrelationsaresignificantatp<0.01level.}

and audiological methods that the control group did not have ETD. Inclusion criteria for the control group were listedasansweringallscalequestions,nothavinganyacute or chronicsinonasalpathology, anyacuteor chronic otitis media, tinnitus, hearing loss or obstructive sleep apnea during ENT examination. Afterwards, patient data sheet related to demographic features and ETDQ-7 forms were appliedtoallcontrolgroup.

DetectingEustachiantubedysfunction

Routine ENT examination was performed to the individ-uals.Afterthat,tympanometricanalysisandWilliamstest were conducted (Interacoustics AZ 26 clinical impedance audiometer, Assens, Denmark). Results obtained from WilliamstestwererecordedforeachearasP1,P2andP3. IfpressuredifferencesbetweenP1---P2andP2---P3wereless than10daPaor pressuredifferencebetweenPmax−Pmin waslessthan 15daPa, the testsubjectwasconsidered to haveETD.10,11

Eustachiantubedysfunctionquestionnaire-7 BasedonsymptomsofETD,thisLikert-typescaleconsisted of seven questions,witha responseof ‘‘1’’ indicating no problem and ‘‘7’’ indicating a severe problem. When an overallscoregothigher,itwasconsideredtobeanincrease intheseverityofthedisease.InETDQ-7patientswereasked iftheyhadpressure,painintheears,afeelingofcloggedor muffledhearing,earsymptomsduringsinusitisorcommon cold,crackling soundsor tinnitusinoneor bothearsover thepreviousonemonthperiod.Thelowesttotalscorewas 7whilehighestwas49inthisscale.4

Procedure

Internationallyaccepted stepsdefined inrelatedmethods were used during language adaptation of the scale.12---14

Whilstmakingcultural/languageadaptationforETDQ-7, ini-tiallytwoacademicianscarriedoutblindtranslationsfrom EnglishtoTurkish.Thereafter,theaccordancebetweentwo languageswascheckedbyalinguist.Finally,thescalewhich wastranslatedintoTurkishwastranslatedintoEnglishagain byabilingualacademician.Ultimately,nomeaninglosswas detectedamongscalewording.Consideringexpertopinions, afinalstateforthescalewasdetermined.Lateron,asapilot study,fivepatientswererequestedtofilloutTurkishversions of thescale andasked if therewere any cognitive disso-nancetobecorrected.Heedingtheiropinions,allobscure sentencesin Turkish versionof ETDQ-7 were enhanced to achievecomprehensibility.Then,thescale wasappliedto allparticipants.Twoweeksafterthefirstevaluation,15of thecasesfilledoutthescaleagainwithout anytreatment intervention.

Statisticalanalysis

ThedatawereevaluatedwithSPSS20.0packageprogramfor Windows(IBMCorporation,Armonk,NewYork,USA). Confor-mityofthedatatonormaldistributionwasestimatedwith theKolmogorov---Smirnovtest.Limitingvaluewasspecified as20%infloor-ceiling effects.15 _{Pairedsamplettest from} parametrictestswasusedtoseeiftherewasadifferencein test---retestscores.Correlationsbetweentest---retestresults wereobtained withPearsoncorrelation analysis.Number, percentage,meanandStandardDeviation(SD)werelisted asdescriptivedata.Independentsamplettestwasusedto makecomparisonbetweenitemandtotalscoresfortheETD andcontrolgroups inETDQ-7 scale. Mann---WhitneyUtest wasusedtocomparetheETDandcontrolgroups’middleear pressure.Known-groupsmethodwasusedin validity anal-ysis. Floor-ceiling effect, test---retest method, item-total score correlation and Cronbach’s alpha coefficient as an internalconsistency analysiswereusedin reliability anal-yses.Forstatisticalsignificancelevel,p-valuewasaccepted tobelessthan0.05.

Results

Twenty five (62.5%) patients of total 40 cases diagnosed withETDwerefemaleand15(37.5%)weremale.Themean ageofthecontrolgroupwas36.4±10.2(min 18,max54) while 39.8±11.8 years old (min 18, max 62) in the ETD group.In terms of ageand gender, nostatistically signifi-cantdifferencewasdetectedbetweentheETDandcontrol groups (p<0.05).Forboth leftandright ears, middle ear pressuresinpatientswithETDwerefoundtobestatistically significantlymorenegativecomparedtothecontrolgroup (p<0.001,Mann---WhitneyUtest).Itwasalsodetectedthat floor-ceilingeffectsofthe2ndand3rdquestionsinthescale wereabove20%.Cronbach’salphacoefficientwasequalto 0.714(very high) for theentire instrument. As seen from

Table 1, none of the Cronbach alphas were greater than 0.714ifanyitemwasdeleted.

Thetest---retestreliabilitycoefficientforthetotalscale wasdetermined as0.792(Table2). Therewasno statisti-callysignificant differencedetected while comparingfirst andlastevaluationscoresofthescaleitemsintest---retest reliabilityexceptItem2(Table3).IntheETD group,total andeachitemscores werefound significantlyhigherthan thecontrolgroup(p<0.001)(Table4).

Discussion

Therearesubstantialscalesthatareusedroutinelyinthe field of otorhinolaryngology. Sino-Nasal Outcome Test 22

Table2 Pearson correlationcoefficientfor eachitemin test---retestreliability.

Scaleitemno r

Item1---retestItem1 0.733a

Item2---retestItem2 0.621b

Item3---retestItem3 0.827a

Item4---retestItem4 0.663a

Item5---retestItem5 0.732a

Item6---retestItem6 0.763a

Item7---retestItem7 0.806a

Testtotal---retesttotal 0.792a

a _{Significantcorrelationsatp<0.01level.} b _{Significantcorrelationsatp<0.05level.}

(SNOT-22)isafrequentlyusedLikert-typescalewhich eval-uatescomplaintsaboutnoseandsinuses.16 _{Similarly,Otitis} Media 6-ItemQuality ofLife Survey(OM-6) is usedtotest thequalityoflifeforpatientswithchronicotitismedia.17 McCoul et al. contributed ETDQ-7 as a disease specific Likert-typescaleforEustachiantubedysfunctioninclinical practice.AuthorsusedbothOM-6andSNOT-20testsduring theprocessofdevelopingthisscale.4

McCoul etal. stated that specificity and sensitivity of this scale for ETD was100%. Although theyprepared this scale with nineitems initially, two of thequestions were omittedowingtoachievingahigherCronbach’salphawith seven items and ETDQ-7 was finalized accordingly. More-over,duringinternalconsistency analysisCronbach’salpha

Table3 Comparisonoftest---retestitemscoremeans. Scaleitemno Testscore(n=15)

Mean±SD Retestscore(n=15) Mean±SD t pa Item1 4.7±1.3 4.4±1.7 1.09 0.29 Item2 3.6_±1.2 3.0_±0.9 2.35 0.03 Item3 5.0±1.9 4.7±1.6 1.16 0.26 Item4 5.0_±2.2 4.8_±1.8 0.59 0.56 Item5 3.6±1.7 3.8±1.5 0.64 0.53 Item6 3.2±2.0 3.1±1.7 0.38 0.70 Item7 4.3±1.9 4.2±1.8 0.43 0.67 Total 29.7±6.0 28.1±5.2 1.65 0.12

a_{Pairedsamplettest.}

Table4 ComparisonofETDandcontrolgroups’itemscores. Scaleitemno ETDgroupscore(n=40)

Mean±SD

Controlgroupscore(n=40) Mean±SD t pa Item1 4.3±1.7 1.1±0.4 10.9 <0.001 Item2 3.1±1.7 1.2±0.4 6.4 <0.001 Item3 4.9_±1.8 1.2_±0.4 12.7 <0.001 Item4 4.2±2.3 1.3±0.6 7.3 <0.001 Item5 4.1_±1.7 1.1_±0.5 10.3 <0.001 Item6 3.5±2.0 1.2±0.5 6.7 <0.001 Item7 4.5±1.9 1.1±0.3 10.7 <0.001 Total 28.7±8.2 8.5±1.7 15.1 <0.001

coefficientwasfoundas0.711.4_{Consistentwiththese} find-ings,Cronbachalphacoefficientwasfound as0.714inthe present study. As Cronbach alpha coefficient approaches one,internal consistency reliabilityincreases.8 _{The result} achievedinthestudyassertsthatthescalehasinternal con-sistencyandhasahighdegreeofreliability.Beinga7-item scaleanditseaseofapplicationareETDQ-7’smost impor-tantadvantages.4 _{Hence, itcan beusedin} otorhinolaryn-gologypracticesandETD-relatedresearchesprevalently.In 2014,itsGermanvalidityandreliabilitystudywasdoneby Schroderet al.18 _{After implementingvalidity and} reliabil-ityofthe scaleintodifferentlanguages, theusageof the scaleincreasedandwasregardedasaquantitativemethod forinvestigatingETDinstudies.Liuetal.statedthatETDQ-7 couldbeusedasahelpfulmethodfordiagnosisinadultswith serousotitis media.6 _{VanRoeyen etal.investigatedvalue} anddiscriminativepowerofETDQ-7andstatedthatETDQ-7 isabeneficialdisease-specificscale,whereasthistestisnot convenientfordiscriminatingobstructiveETDandpatulous Eustachian.19

ParticipantshaddifficultyinscoringItem4(‘‘Increasein earsymptomswhen you havea cold or sinusitis’’)ifthey didnotencounterthesediseasesoverthelastmonth dur-ingpilotstudy.Neitheranotenoracriticismwasdetected inoriginalscaleor invalidityandreliabilityedition ofthe scale.Thus,asauthors,itisagreedtoannotateafootnote undertherelatedscale aboutthisinquiry. Forthe Turkish versionofthescaleafootnotestating‘‘ifyoudonot com-plainaboutbothdiseasesforthelastmonth,pleasemark1 (Notaproblem)’’wasadded.

The lowest mean score was detected for item 2 (3.1±1.7) while Item 3 was marked as the highest (4.9±1.8) in the scale. Furthermore, in Items 2 and 3, floor-ceilingeffectsweregreaterthan20%.Thoseitemswe suggest being interpreted carefully. These results showed similaritieswithanalysesofMcCouletal.andSchroderetal. whoinvestigatedtheGermanvalidityofthescale.4,18_Thirty percentagesofpatientsgivingthelowestscore(1/no prob-lem)forItem2inthescale,‘‘paininears’’question,was apredictableoutcome.Itispossiblybecausemanypatients donot define earache in chronic ETD.18 _{InItem 3,where} auralfullnesswasinvestigated,patientswereaskedifthey hadafeelingthattheirearswerecloggedor‘‘underwater’’ and27.5%ofpeoplenoteditwithhighestscore(7/severe problem)sincethismightbeabout beingthemost distur-bing complaint for ETD. In thestudies conducted by Park etal.,ETDwasdenotedasthemostcommonotologic dis-easeamongpatientsthatappliedtothehospitalwithaural fullnesscomplaint.20

In our study,the test---retestreliabilityfor overall test score wasfound as0.792 (Table 2). Similarly, test---retest reliabilitywasdeclaredas0.78inMcCouletal.’sstudy.4_Both results indicatetousthat reliabilityfor thescale is rela-tivelyhighforthetestsappliedatdifferenttimes.Moreover, inourstudy,test---retestcorrelationvaluewasdetectedto varybetween0.621and0.827.Theseresultsleadustothe factthatevenifeveryiteminthescaleisansweredbythe samepatientatdifferenttimes,responsesshowconsistency. Questionsshowedconsistencyovertimebothfortotalscale andforitem.

Onceeachitemandtotalscorepointaveragesobtained fromcontrolgroup(n=40)werecomparedwithETDgroup, statistically significant difference wasdetected item and totalscore-wise(p<0.001).Moreover,noneofcasesin con-trolgrouphadtotalscalescoresgreaterthan14.5whichwas statedasathresholdinMcCouletal.Forallpatientswith ETD,total scale scores were observedto begreater than 14.5. These results might be interpreted such that while thisscaleisavaliddiscriminationbetweenpeoplewithand without ETD,it also statesthat this scale is particular to ETD.

Conclusion

In conclusion, a high-level of validity and reliability was determinedinconsequenceofstatisticalanalysesforTurkish versionofEustachiantubedysfunctionquestionnare-7.This scaleisrecommendedfor screeningofETDandevaluating severityofthedisease.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

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