www.bjorl.org
Brazilian
Journal
of
OTORHINOLARYNGOLOGY
ORIGINAL
ARTICLE
Hearing
in
Noise
Test
Brazil:
standardization
for
young
adults
with
normal
hearing
夽
,
夽夽
Andressa
Forlevise
Sbompato,
Lilian
Cassia
Bornia
Jacob
Corteletti,
Adriane
de
Lima
Mortari
Moret,
Regina
Tangerino
de
Souza
Jacob
∗AudiologyandSpeechPathologyDepartment,FaculdadedeOdontologiadeBauru,UniversidadedeSãoPaulo(USP),Bauru, SP,Brazil
Received29January2014;accepted22July2014 Availableonline9June2015
KEYWORDS
Speechperception; Adult;
Noise; Hearingloss
Abstract
Introduction:Individuals with the same ability of speech recognition in quiet can have extremelydifferentresultsinnoisyenvironments.
Objective:Tostandardizespeech perceptioninadultswith normalhearinginthefree field usingtheBrazilianHearinginNoiseTest.
Methods:Contemporary,cross-sectionalcohortstudy.79adultswithnormalhearingand with-outcognitiveimpairmentparticipatedinthestudy.ListsofHearinginNoiseTestsentences wererandomlyinquiet,noisefront,noiseright,andnoiseleft.
Results:Therewerenosignificantdifferencesbetweenrightandleftearsatallfrequencies tested(pairedt−1test).Norweresignificantdifferencesobservedwhencomparinggenderand interactionbetweentheseconditions.Adifferencewasobservedamongthefreefieldpositions tested,exceptinthesituationsofnoiserightandnoiseleft.
Conclusion:Resultsofspeechperceptioninadultswithnormalhearinginthefreefieldduring differentlisteningsituationsinnoiseindicatedpoorerperformanceduringtheconditionwith noiseandspeechinfront,i.e.,0◦/0◦.ThevaluesfoundinthestandardizationoftheHearing inNoiseTestfreefieldcanbeusedasareferenceinthedevelopmentofprotocolsfortestsof speechperceptioninnoise,andformonitoringindividualswithhearingimpairment.
© 2015Associac¸ãoBrasileira de Otorrinolaringologiae CirurgiaCérvico-Facial. Publishedby ElsevierEditoraLtda.Allrightsreserved.
夽 Pleasecitethisarticleas:SbompatoAF,CortelettiLCBJ,MoretALM,JacobRTS.HearinginNoiseTestBrazil:standardizationforyoung
adultswithnormalhearing.BrazJOtorhinolaryngol.2015;81:384---8.
夽夽Institution:PhonoaudiologyDepartment,FaculdadedeOdontologiadeBauru,UniversidadedeSãoPaulo(USP),Bauru,SP,Brazil.
∗Correspondingauthor.
E-mail:reginatangerino@usp.br(R.T.d.S.Jacob).
http://dx.doi.org/10.1016/j.bjorl.2014.07.018
PALAVRAS-CHAVE
Percepc¸ãodafala; Adulto;
Ruído; Perdaauditiva
HearinginNoiseTestBrasil:padronizac¸ãoemcampolivre---adultoscomaudic¸ão
normal
Resumo
Introduc¸ão: Indivíduoscomasmesmashabilidadesdereconhecimentodefalanosilênciopodem apresentarresultadosextremamentediferentesemambientesruidosos.Objetivo:Padronizar apercepc¸ãodafalaemadultoscomaudic¸ãonormalemcampolivrenoHearinginNoiseTest Brazil.
Método: Estudodecoortecontemporâneocomcortetransversal.Participaram79adultoscom audic¸ãodentrodospadrõesdenormalidade(normo-ouvintes),semalterac¸õescognitivas.Foram aplicadasaleatoriamentelistasdesentenc¸asdoHINTnosilêncio,ruídoàfrente,ruídoàdireita, ruídoàesquerda.
Resultados: Nãohouvediferenc¸asignificativaentreorelhasparatodasasfrequênciastestadas, sexoeinterac¸ãoentreascondic¸ões.Observou-sediferenc¸aentreascondic¸õestestadas,exceto entreassituac¸õesderuídoàdireitaeruídoàesquerda.
Conclusão:Osresultadosdapercepc¸ãodafalaemadultoscomaudic¸ãonormalemcampolivre em diferentes situac¸õesde escutanoruído indicarampior desempenhonasituac¸ãoruídoe falaàfrente,ouseja,0◦/0◦.Osvaloresencontradosnapadronizac¸ãodoHINTemcampolivre poderãoserutilizadoscomoreferêncianaconstruc¸ãodeprotocolosparautilizac¸ãodetestes depercepc¸ãodafalanoruídoenoacompanhamentodeindivíduoscomdeficiênciaauditiva. ©2015Associac¸ãoBrasileiradeOtorrinolaringologiaeCirurgiaCérvico-Facial.Publicado por ElsevierEditoraLtda.Todososdireitosreservados.
Introduction
Speechperceptioninnoise
Speechrecognitionisessentialfor socialintegration,asit enables efficient interpersonal communication. The abil-ity to understand speech in the presence of background noise is a major challengefor any listener, especiallyfor thosewithhearingimpairment.1Theevaluationofthisskill shouldbe considered averyimportant aspect tobe mea-suredinhumanauditoryfunction,asitallowsforevaluation of receptive communicative function, providing data on howthesubjectfunctionsineverydaylisteningsituations, by means of easily quantifiable information.2,3 Speech is an acoustic signal in which information is transmitted by means of changes of frequency, intensity, and time. The normal auditory system has the inherent ability to iden-tify, process, andencode this information.4,5 The aspects ofvariabilityinspeecharewell known,namely: speaker’s gender,rateofspeech,dialect,vocabulary,and grammat-icalcomplexity.6 Thus,at the timeofassessment, factors suchasthetypeandlevelofpresentationof thematerial andofitsresponse,andlistenercharacteristics, including languageandlisteningexperience,candirectly affect the outcome.7---9
In daily life, many communicative situations occur in environmentswherelistening is impaired bythepresence ofcompetitivenoise.4,10 Becauseofthis,andknowingthat thesamepatientmayhaveverydifferentabilitiesforspeech recognitioninaquietenvironmentthaninanoisyone,itis importanttoemphasizetestinginanoisyenvironment.3,11
Inordertomeasureapatient’shearingdifficulties,the phonoaudiologistneedstoresorttoabatteryofteststhat not only willallow the identification of a potential hear-ingloss,butalsowillanalyzetheunderstandingofauditory
stimuli,including speech in clinical situations and mainly underconditionsclosetothosefoundineverydaylife.12
Research shows that patients with normal hearing have their speech perception affected by environmental noise.3,9,13,14Complaintsofdifficultyunderstanding speech inthepresenceofnoisehavebecomeincreasinglycommon, whetherornotsomehearingimpairmentexists.15Toassess anddiagnosetheimpairmentofhearingcapacityofan indi-vidual,severaltestsareusedinclinicalpractice.However, these tests are unable todetect the patient’s functional abilitytoperceiveandunderstandspeechinnoisy environ-ments,asthesetestsareappliedinquietenvironments.3
In Brazil,speech-in-noise tests arenotyet part of the conventionalaudiologicbattery;thecomparisonof perfor-mance, in quiet and in noisy environments, is not often performed, based on protocols already standardized. In addition,fewstudiesindicatetheperception-of-speech per-formance in noisy environments expected for adults with normalhearinginthefreefield,especiallywiththevalues obtainedintheHearinginNoiseTest(HINT).1,16,17
HINTisaspeechrecognitioninnoisetestsimulating hear-ingsituations similar toeveryday life, andis available in severallanguages,includingBrazilianPortuguese.18
HINTassessestheauditoryfunctionbymeasuringthe sig-nal/noise(S/N)ratiofor sentencesinaquietenvironment andinthreenoise conditions:(a)noise in front(speaking in front and noise at 0◦ azimuth); (b) noise to the right (speaking in front and noise at 90◦ tothe right), and (c) noisetotheleft(speakinginfrontandnoiseat 90◦ tothe left).TheHINTtestconsistsof12listsof20sentenceseach, totaling240representative sentencesofeveryday speech. The sentences are short,phonemically balanced, easy to understand,andwiththesamedegreeofdifficulty.16 How-ever,foritsvalidation,theHINT-Brazilwasappliedonlyvia
freefieldconditions.18 Thus,itsapplicationisnotfeasible for users of individual hearing aids and/or with cochlear implants.Incontrast,manyinternationalstudiesuseHINTin freefieldconditionstoassesstheperformanceandspecific characteristicsofauxiliaryhearingdevices.19---23
Calibrationofthetestenvironment
Thevariablesthataffectin-noisespeechrecognitioncanbe divided into categories and subcategories: variables from stimulusused--- styleandcontentofthesentences,in-noise intelligibility level, type of noise and loudspeaker; varia-blesofstimuluspresentation---method,transducer;subject variables---hearingloss,auditoryprocessing,age,language, cognition;subject’sresponsevariables---responsechannel, classificationmethod;variablesofsubject’sperformance ---reliability,validity, sensitivity and specificity. It would be helpfultounderstandthevariablesaffectingspeech recog-nitioninordertoguidethedevelopmentofnewtestsand alsotoidentifyfactorsthatcouldexplainresultsthat devi-atefromthosealreadydocumented.1
Thecalibrationofthefreefieldshouldbeestimatedin situ,sincetheresultsobtainedbydifferentresearchersvary widely;thisvariationisjustifiedbyanumberofaspectsthat caninterferewiththemeasurementsandthat,therefore, should be considered, such as room size, acoustic condi-tions, whetheror not areflective surface exists, level of reverberation,calibration,andeventhenumberofpeople withinthetestenvironment.11,24
Thus,itisemphasizedthatitiscriticalfortheevaluator tohavehis/herownparameterforthetestsite;the evalua-toralsomustconsiderthesituationinwhichthetestisbeing conducted.12Authorspointtotheneedforharmonizationof in-noiseassessmentsin differentlanguages, tostrengthen theclinical practicebasedonevidenceintheaudiological community.25 Inordertocalibratethein-noisetest inthe freefieldandtocompensatefortheacousticeffectsofthe environment,itisrecommendedthattheimplementationof HINTbeperformedfirstinindividualswithnormalhearing.24 Basedontheseconsiderations,thisstudyaimedto stan-dardizetheapplicationoftheHINT-Brazilinthefreefieldin normalhearingadultsubjects.
Method
This wasacross-sectional study,conductedat the Educa-tionalAudiology Laboratoryin 2011,withapproval bythe ResearchEthicsCommittee(Protocol129/2010).
Inthisstudy,onlyindividualswhoagreedwiththe pro-ceduresnecessaryforconductingtheexaminationandwho signedtheinformedconsent,afterhavingreceived informa-tiononthepurposeandmethodologyoftheproposedstudy, wereenlisted.
Theadoptedinclusioncriteriawere:agebetween18and 59years,audiometricthresholdswithinnormallimits,26and absenceofearwaxplugorotherchangesintheexternalor middleearwhichcouldmodifythetestperformance.
Thesample wasselectedbyconvenienceandconsisted of79adultsubjects,29malesand50females,aged19---44 years(mean,24years).
The audiological evaluation occurred following an otoscopicexaminationperformedbytheService’s otolaryn-gologist, and consisted of pure tone audiometry by air conductionatfrequenciesof250---8000Hz.Toobtainthese measures,adigitaltwo-channelaudiometer(Madsen,model Midimate622)wasused,alongwithTDH35supra-auricular headphones.Thetestwasconductedinasoundproofbooth. Toassessthe in-noisespeechperception,the following equipmentwasused:theHINTPro7.2AudiometricSystem; twostereoloudspeakersforthefreefield;acomputerwith CDrecorder;printer;andasound-treatedroom.
The test was conducted in the free field condition in a sound-treated room, according to the HINTPro 7.2 AudiometricSystemoperatinginstructionsmanual.HINTPro consistsofequipmentwithinterfaceconnectedtothe com-puter,whichpermitstheuseofHINT.Theinstallationofthe specificsoftwareforthetestonthecomputerisrequired, andthefreefieldstereoloudspeakerswerecoupledto HINT-Pro7.2.
Each listof 20 sentenceswas appliedin the following situations:quiet(Q),noisefront(NF),noiseright(NR),and noise left (NL) and compound noise (CN). The sentences werepresented at0---0◦ azimuth, andthelevelof presen-tationwasinitiallysetat45dBA,andvariedinstepsof4dB and2dB,accordingtothecorrectrepetitionofthelevel.
However,thecompetitivenoisewasintroducedat0---0◦, 0---90◦,0---180◦,and0---270◦ azimuth,at afixedintensity of 65dBA.27 Thelistsofsentencesandtheorderofnoise pre-sentationwereselectedandpresentedrandomly.Thescore wasexpressedindB,representingtheS/Nratiothreshold.
Fordataanalysis,thepairedt-testandtwo-wayANOVA wereused.
Results
Therewasnosignificantdifferenceamongears,gender,and interactionamongconditions.Wedidobserveadifference amongtheconditionstested(Table1).
Discussion
Thesubjectsofthisstudyreportednodifficultyundertaking the test; theyunderstood the instructions andperformed properly.
Asshown inTable 1,themean valuesobtainedfor the in-noise speech recognition threshold (SRT --- HINT Brazil) ranged from −6.47 to−3.20 for different listening situa-tions.Theliteraturecontainstwostudies16,24 thatdescribe
Table 1 Results obtained in different noise conditions. Equallettersindicatenosignificantdifference.
Condition Mean(dBNA) SD
Quiet 10.3a
NL −6.47b 1.55
NR −6.46b 1.63
CN −4.83c 0.80
NF −3.20d 0.89
theperceptionofspeechin-noiseperformanceexpectedfor adultswithnormalhearinginthesamelisteningsituation ---inthefreefield.Thefirststudy16proposesvalues approach-ingthosefindingsofthisstudyforalltestconditions,while theother24 found betterresults; thiscanbe explainedby thefactthatthecharacteristicsofthespeechmaterialand of the individuals whoparticipated in thetest canaffect intelligibility.Thesecharacteristicsincludethewords’ pho-netic similarity,the rate of speechand theclarity of the speaker,thenaturalnessofthespeaker’svoice,thegender ofthesubject,andhis/herdialect.24,28
The languageskills of thelistener interact with gram-matical and lexical properties of the material (speech). Likewise,thelistener’scognitiveandmemoryabilities inter-act withthecomplexity andduration of thediscourse. In addition,theage atwhichthelanguagewasacquired and theprimaryor secondarystatusof thelanguageaffectits intelligibility.24 Different speakers who speak in different languagesandtonesareusedtorecordtheHINTsentences. Therefore, the masking effects on a particular speech samplebyspectralnoiseareunpredictable,contributingto anunwantedsourceofvariabilityinthresholdmeasures.24 Anotherfactor thatcaninterfereintheresultsisthe cali-brationfor thefreefieldin situ,withdifferentconditions fromonetesttoanother.Inastudyonspeechrecognition in thefreefield,and alsobasedontheliterature review, it wasfound thatthe present resultswere differentfrom thoseofother studies,12,16,24 possiblybecauseof variables thatcanbefoundin theevaluationofthefreefield envi-ronment,suchasroomsize,acousticconditions,whetheror notareflectivesurfaceexists,aswellasreverberationand calibrationlevels.10Oneofthesestudieswasnotconducted inBrazil.24
The worst S/N ratio is obtained when the speech and noiseareinthesameposition,explainingtheresultsfound for NF. According to the literature, the highest (worst) thresholds occurwhen speechandnoise arepresented at thesamelocation,thatis,speechandnoiseat0◦infrontof thesubject.Theresultsarebetterwhenspeechandnoise areseparatedbyanangleof90◦,withspeechat0◦infront oftheindividual,andthenoisetotherightortotheleftat 90◦,24thebestreportedresultsareseenwhenthenoiseand speechconditionsareseparatedby90◦,withspeechat0◦in frontoftheassessedindividualandthenoiseat90◦ tothe rightortotheleftofthesubject,3,16,29whichcorroborates thefindingsofthepresentstudy.
ThestatisticaldifferencebetweenS/Nratiosobtainedat 0---0◦inrelationtothoseobtainedwiththenoisepositioned at0---90◦ occursbecause,whenmovingthesoundfromthe in-front position tothe lateral position in relation to the subjectassessed,thesoundstimuluspresentedlaterallyis notequallyperceivedbybothears,contrarytowhatoccurs whenthesoundsourceislocatedinfrontofthesubject.This differenceinperceptionisduetothepresenceofinteraural timeandintensitydifferences,thatoccurwhenspeechand noisesourcesarespatiallyseparated.7,29
Importantly,theresultsofthecompoundnoise(CN)are generatedautomaticallybytheHINTProsoftware, accord-ingtotheformulaRC=(2×NF+NR+NL)/422.Althoughage
perseisnotanessentialfactorinspeechperception,there arereports inthe literatureofperformance deterioration in speechperception with increasingage --- in association
withthenaturalagingprocess.1Consideringthatthepresent studygroupwascomposedofyoungadults(between19and 44years,mean24years),futurestudieswitholdergroups ofadultsorevenwithelderlypatientswouldbewelcome.
Subjects of both genders and with ages between 18 and 50 years took part in the standardization of HINT Brazil18 using headsets. In tests performed in-noise, the authorsconsiderquestionabletheneedforadjustmentswith the introduction of visual cues for the older population, evenif only for previous trainingto the test application, since,whenthestimulusisgivenonlyby ear,older adults demonstratelesspoorperformancesinspeechrecognition, whencomparedtoyoungadultsoreventonormalhearing individuals.30,31Thesameoccurswhenonlyvisualcuesare used.30,32,33Overall,regardlessofage,itiscommonthatin difficultlisteningsituationsthelistenerperformslipreading tofacilitatehis/herunderstanding.30,34
Conclusion
Valueswere developed for thestandardization ofHINT in thefreefieldduringdifferentlisteningsituationsinanoisy environment.Theresultsofspeechperceptioninadultswith normalhearingshowedworseperformanceinthesituation ofNF,i.e.,0---0◦.
Theseresultscouldbeusedasareferenceinthe cons-tructionofprotocolsfor useofspeechperceptiontestsin noise,andinmonitoringindividualswithhearingloss.
Funding
Thisstudy wassupported by PIBIC(ProgramaInstitucional deBolsasdeIniciac¸ãoCientífica)/RUSP(Reitoriada Univer-sidadedeSãoPaulo).
Conflicts
of
interest
Theauthorsdeclarenoconflictsofinterest.
Acknowledgements
PIBIC/RUSP.
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