www.jped.com.br
ORIGINAL
ARTICLE
Translation
and
validation
of
the
Pediatric
Daytime
Sleepiness
Scale
(PDSS)
into
Brazilian
Portuguese
夽
Érico
P.G.
Felden
a,∗,
Joana
D.
Carniel
a,
Rubian
D.
Andrade
a,
Andreia
Pelegrini
a,
Tâmile
S.
Anacleto
b,
Fernando
M.
Louzada
baPost-graduatePrograminHumanMovementScience,HealthSciencesResearchCenter,UniversidadedoEstadodeSanta
Catarina(UDESC),Florianópolis,SC,Brazil
bPost-graduatePrograminCellandMolecularBiology,HumanChronobiologyLaboratory,UniversidadeFederaldoParaná(UFPR),
Curitiba,PR,Brazil
Received6March2015;accepted27May2015 Availableonline12December2015
KEYWORDS Translating; Validationstudies; Disordersofexcessive somnolence;
Child; Adolescent
Abstract
Objective: TheaimofthisstudywastotranslateandvalidatethePediatricDaytimeSleepiness
Scale(PDSS)intoBrazilianPortuguese.
Methods: Thetranslation/validationprocesswascarriedoutthroughtranslation,back
trans-lation,technicalreview,assessmentofverbalcomprehension/clarityofthescalebyexperts andafocusgroup,test---retest, andapplicationofthetool.Thereproducibilityanalysiswas performedbyapplyingthePDSSintest---retest;internalconsistencywasverifiedbyapplying thescalein90childrenandadolescents.
Results: Themeanscore ofthe sumofPDSSquestionswas 15.6(SD=5.0)points.The PDSS
showedappropriateindicators ofcontentvalidation andclarityfor theBrazilianPortuguese version.TheinternalconsistencyanalysisshowedaCronbach’salphaof0.784.ThePDSSshowed adequatereproducibility.ThePDSSscoresshowedasignificantandnegativecorrelationwith timespentinbed(r=−0.214;p=0.023).
Conclusion: TheBrazilianPortugueseversionofthePDSSshowssatisfactoryindicatorsof
valid-ityandcanbeappliedinclinicalpracticeandscientificresearch.
©2015SociedadeBrasileiradePediatria.PublishedbyElsevierEditoraLtda.Allrightsreserved.
夽 Pleasecitethisarticleas:FeldenÉP,CarnielJD,AndradeRD,PelegriniA,AnacletoTS,LouzadaFM.Translationandvalidationofthe PediatricDaytimeSleepinessScale(PDSS)intoBrazilianPortuguese.JPediatr(RioJ).2016;92:168---73.
∗Correspondingauthor.
E-mail:[email protected](É.P.G.Felden). http://dx.doi.org/10.1016/j.jped.2015.05.008
PALAVRAS-CHAVE Traduc¸ão;
Estudosdevalidac¸ão; Transtornosda sonolênciaexcessiva; Crianc¸a;
Adolescente
Traduc¸ãoevalidac¸ãodaPediatricDaytimeSleepinessScale(PDSS)paraoportuguês
doBrasil
Resumo
Objetivo: EsteestudotevecomoobjetivotraduzirevalidarPediatricDaytimeSleepinessScale
(PDSS)paraoportuguês(Brasil).
Método: O processo da traduc¸ão/validac¸ão deu-se por meio da traduc¸ão, retro traduc¸ão,
revisão técnica, avaliac¸ãoda compreensãoverbal/clarezado questionárioporespecialistas e porgrupofocal,teste-retestee aplicac¸ãodoinstrumento.A análisedereprodutibilidade realizou-se por meio da aplicac¸ão da PDSS em teste-retestee a consistência interna pela aplicac¸ãodaescalaem90crianc¸aseadolescentes.
Resultados: Apontuac¸ãomédiaverificadanosomatóriodasquestõesdaPDSSfoi15,6(5,0)
pon-tos.APDSSapresentouadequadosindicadoresdevalidadedeconteúdoeclarezadelinguagem emportuguêsdoBrasil.AanálisedaconsistênciainternaidentificoualfadeCronbachde0,784. APDSSapresentouadequadareprodutibilidade.OsescoresdaPDSSapresentaramcorrelac¸ão negativaesignificativacomotemponacama(r=-0,214;p=0,023).
Conclusões: A versãoem português daPDSSapresenta satisfatórios indicadoresdevalidade
podendoseraplicadanapráticaclínicaeempesquisascientíficas.
©2015SociedadeBrasileiradePediatria.PublicadoporElsevierEditoraLtda.Todososdireitos reservados.
Introduction
Excessive daytime sleepiness (EDS) is characterized by an increased sensation of sleepiness and decreased alertness.1,2 It is oneof themain effects of low-duration
and/or poor-quality sleep, and is associated with learn-ing and behavioral problems, low cognitive performance, and attention and concentration deficits.3---7 EDS can be
observedatallstagesoflife.However,studiespointtoits increaseinprevalenceinadolescence,alifestageinwhich adelayedsleepphasecharacterizedbylatertimestosleep andwake8,9andreducedsleepinghours10canbeobserved.
Gibsonetal.9identified68%ofadolescentswithEDSinthe
earlyhoursofthemorninginastudyperformedinCanada. Similarly,Souzaetal.,11inasampleofBrazilianadolescents,
identified a prevalence of 55.8% of EDS. Nevertheless, as discussed by Pereira etal.,2 Brazilian literature is scarce
withregardtotheproceduresandtoolstoevaluateEDSin childrenandadolescents.
The gold standard for EDS assessment is the Multiple SleepLatency Test, whichis performed in the laboratory, makingthisassessmentunfeasibleinmanycircumstances.12
RegardingthemostwidelyusedquestionnairetoassessEDS, theEpworthscale,13ithasimportantlimitationsrelatedto
thecontentofitsquestionstobeusedinpediatric popula-tions.
ThePediatricDaytimeSleepinessScale(PDSS),byDrake etal.,3hasbeenusedinstudieswithforeignsamples3,7,14---17
and constitutes an important tool for the assessment of excessivedaytime sleepiness in childrenand adolescents. However,translationandvalidationstudiesofthisscalefor useinBrazilwerenotfoundintheliterature.Theaimofthis studywastotranslateandvalidatethePDSSintoBrazilian Portuguese.
Method
The PDSS aims to assess the occurrence of EDS, and was validated for children and adolescents aged 11---15 years.3Itconsistsofeightmultiplechoicequestions.Each
question has five response options, using a Likert scale: 0=never; 1=almost never; 2=sometimes; 3=frequently, and 4=always. The questions, with the exception of the third,whichhasareversescore,haveadirecteffect,with higherscoresindicatingmoresleepiness.Intheend,thesum ofquestionsscoresisobtained,withthescorescaleranging fromzeroto32points.
The process of translation and cultural adaptation preserved the assessment of equivalences suggested by Herdmanetal.18andReichenheimetal.19 Theprocesswas
carried out according to the following steps: translation, back translation, technical review, assessment of verbal comprehension and clarity of the questionnaire by field experts,assessmentofthetoolclaritywithafocusgroup, test---retest, andfinally, the application of the completed tool.
Initially, threeexperienced researchers whoare fluent in English translated the original tool from English into BrazilianPortuguese.Theresearchersdiscussedthe discrep-anciesinthetranslationsanddefinedaBrazilianPortuguese version,whichwasthenbacktranslatedbyanative English-speakingexpert.
questions, and adequacy to the population aged 11---15 years.
Next,afocusgroupconsistingoftenchildrenand adoles-centsofbothgenders,aged10---17years,wasusedtoassess theclarityandunderstandingofthequestions,thusdefining thefinalPortugueseversionofthePDSS.
Fortheinternalconsistencyanalysisconductedthrough Cronbach’sAlpha,thetoolwasappliedin 90childrenand adolescentsofboth genders(51girls)enrolledinthefinal yearsofelementaryschool(59.3%)andhighschool(40.7%), aged10---17 years, witha mean of 15.7 years. Alpha val-ues≥0.7wereconsideredacceptable.20,21Thissamegroup wasasked, througha questionnaire, about their sleeping andwakingschedule.Basedonthe informationabout the sleepingandwakingtime,thetimeinbedwascalculated. Thescalereproducibilitywasanalyzedbasedonthetool’s applicationinasubgroupof30childrenandadolescentswho answeredthescale againoneweek afterthefirst applica-tion.
Theparticipatingchildrenandadolescentswereselected fromtwoprivateschools,oneinFlorianópolis,stateofSanta Catarina, and another in Curitiba, state of Paraná.After requesting permission toconduct the study in the above-mentionedschools,theeducationalcoordinatorsindicated the classes that were available to answer the question-naire. Thus, invitations were sent tothe students of the selectedclassestoobtainauthorizationfromtheirparents or guardians toparticipate in the study.The project was approvedby theEthicsCommittee onHumanResearchof the institution; parents or guardians signed the informed consentandthestudentssignedthetermofconsent.
Themeanandstandarddeviationofthesumofthescale questionswerecalculated.TheWilcoxontestwasusedfor theanalysisofthetest---retestdifference.Spearman’s corre-lationtestwasusedfortheanalysisofcorrelationbetween thePDSSscoresandtimeinbed.A5%levelofsignificance wasconsideredfortheinferentialtests.Analyseswere per-formedusing SPSSversion20.0 (IBMCorp.Released 2011. IBMSPSSStatisticsforWindows,version20.0;NY,USA).
Results
Translationandculturaladaptation
Fig.1 shows thetranslation andback-translation analysis ofthePDSSquestions(AppendixA).Thequestionsshowed clarity in the comparison between translation and back translation;theproposedfinalversionofthequestionswas contextuallysimilartotheoriginal oneregarding the lan-guageexpressions.However,anadaptationwascarriedout in question seven for better understanding, based onthe adviceoftheareaspecialistandthefocusgroup.
Expertevaluation
The experts were asked about the clarity and linguistic appropriatenessconsidering the understandingof children andadolescentsintheagerangeoftheoriginaltool.Based onthisassessment,theword‘‘atento’’(aware)wasadded totheword‘‘alerta’’(alert)inquestionthree,duetoa bet-terunderstandingbychildrenandadolescents.Inaddition,
in thisassessment,an expertsuggested adaptingquestion seven:‘‘How oftendoyou need someonetowakeyou up in the morning?’’ The expert suggested considering other waysofawakening,suchasanalarmclock.Thesuggestion wasconsideredvalidandadaptedinthefinalversionofthe scale.
Furthermore, in the final version of the scale, ques-tiontwowasadjustedconsideringtheterms‘‘sleepy’’and ‘‘drowsy.’’ These terms were considered synonyms in the Portugueselanguage,anditisbelievedthattheredundancy usedintheEnglishlanguageisnotnecessaryforthe appro-priate understanding ofthe question inPortuguese. Thus, thefinalquestionwas‘‘Howoftendoyoufeelsleepywhile doingyourhomework?’’
Finally,theexpertswereasked:‘‘Accordingtoyour per-ception,doesthetranslatedtoolconstituteavalidindicator inPortugueseandBrazilianculturefortheinvestigationof excessivedaytimesleepinessinchildrenandadolescents?’’ In this evaluation, only one expert said ‘‘in part,’’ ashe questioned the lack of work-related questions, consider-ingthat,inadolescence,somepeoplearealreadyworking. Becauseof theoriginal scale,it wasdecidednot tomake changes considering work activities. Finally, all experts answered ‘‘yes’’tothefollowing question:‘‘Accordingto your point of view, is the scoring scale in Brazilian Por-tugueseappropriate?’’
Focusgroup
Thefocusgroupwascarriedoutwithtenchildrenand ado-lescentstoverifytheunderstandingofthequestions.This groupwasselectedconsideringtheindicationofthe educa-tionalcoordinationofoneoftheschoolsparticipatinginthe study,accountingfortheavailabilityofstudentsto partic-ipatein thisactivity.Thequestionswereread onebyone tothegroup,andthe children/adolescentswereaskedto explaintheirunderstanding.Inthisstage,theclarityofthe questionswasverified;noparticipantshaddoubtsaboutthe contentofthequestions.
Questionnaireapplication
Agroupofchildrenandadolescentsansweredallthescale questionswiththeobjectivetoanalyzetheinternal consis-tency.Asubgroupansweredthescaleagainoneweekafter the first application. The internal consistency and repro-ducibility results are shown in Table 1. Furthermore, the correlation betweenthePDSSscores withthetimeinbed wascalculated,anda significant negativecorrelationwas found(r=−0.214;p=0.023).
Discussion
Final Back translation
Translation Original
1. How often do you fall asleep or get drowsy during class periods?
1. Com qual frequência você dorme ou sente sono em sala de aula?
1. How often do you sleep or feel sleepy in the classroom?
1. Com qual frequência você dorme ou sente sono em sala de aula?
2. How often do you get sleepy or drowsy while doing your homework?
2. Com qual frequência você dorme ou sente sono ao fazer a lição de casa?
2. How often do you sleep or feel sleepy while doing your homework?
2. Com qual frequência você fica com sono ao fazer a lição de casa?
3. Are you usually alert most of the day?
3. Você está alerta na maior parte do dia?
3. Are you alert most part of the day?
3. Você está atento/ alerta na maior parte do dia?
4. How often are you ever tired and grumpy during the day?
4. Com qual frequência você se sente cansado e mal humorado durante o dia?
4. How often are you ever tired and grumpy during the day?
4. Com qual frequência você se sente cansado e mal humorado durante o dia?
5. How often do you have trouble getting out of bed in the morning?
5. Com qual frequência você tem dificuldades para sair da cama de manhã?
5. How often do you have trouble getting out of the bed in the morning?
5. Com qual frequência você tem dificuldades para sair da cama de manhã?
6. How often do you fall back to sleep after being awakened in the morning?
6. Com qual frequência você volta a dormir depois de acordar pela manhã?
6. How often do you fall back to sleep after being awakened in the morning?
6. Com qual frequência você volta a dormir depois de acordar pela manhã?
7. How often do you need someone to awaken you in the morning?
7. Com qual frequência você precisa de alguém para te acordar de manhã?
7. How often do you need someone to awaken you in the morning?
7. Com qual frequência você precisa de alguém ou de auxílio de despertador para te acordar de manhã?
8. How often do you think that you need more sleep?
8.Com qual frequência você acha que precisa dormir mais?
8. How often do you feel like you need more sleeping time?
8. Com qual frequência você acha que precisa dormir mais?
Figure1 Analysisoftranslationandbacktranslationofthescalequestions.
Table1 Analysisoftheinternalconsistencyofthescalequestions.
PDSS Cronbach’salpha Mean(standarddeviation) p-Value
Test Retest
Sum 0.784 15.6(5.0) 15.6(5.0) 0.725
The consequencesof EDS gobeyond clinical symptoms andemergeinseveraldimensionsoflife,suchasschool per-formance,asshownbythestudyofPerez-Chadaetal.7in
2884Argentineanstudentswithameanageof13.3years. TheArgentineanstudyfoundthatEDSmeasuredbyPDSSwas anindependentpredictorforpooracademicperformancein thedisciplinesoflanguagesandmathematics.
Sleep disorders are increasing in modern society and constitute the main cause of EDS.1,22,23 Thus, there
was a significant correlation between the time in bed and EDS in children and adolescents investigated in the validation of PDSS in Brazilian Portuguese. This result confirms that reported by Drake et al.,3 who found
thatshorter sleepduration wascorrelatedwithincreased EDS.
In order to analyze the EDS in pediatric populations, theliteratureindicatessomedirecttools,suchasMultiple LatencyTest,andindirectones,suchasthePDSS. Consid-eringthattheuseoflaboratorytestsisrestrictedtoafew laboratories,the PDSSisindicated in theclinical practice forthediagnosisandidentificationoftreatmenteffects,as well as in scientific studies, particularly those with large populations.
clinicalresearchandEDSresearchmusttake intoaccount otherfactors,suchasthesleep/wakecyclepattern, time ofuseofelectronicmedia,6andthedietarypattern.24
The PDSS showed satisfactory reliability results (Cron-bach’salpha=0.784).Generally,itis affirmedthatavalue of0.7---0.8isacceptablefortheanalysis,anditisconsidered thatthenumberofquestionsinfluencesthestatistical calcu-lation,becausethenumeratoroftheequationfor˛depends onthenumberofscaleitems.21 Internalconsistencyvalues
weresimilartothatobservedbyDrakeetal.3(Cronbach’s
alpha=0.81)whenvalidatingtheAmericanscale.Also,ina similarstudycarriedoutwiththeEpworthSleepinessScale, theinternalconsistencyanalysisshowedaCronbach’salpha of0.76forthevalidationofBrazilianscaleand0.79forthe validationoftheoriginalscale.25
ThemeanofthesumofthePDSSquestions(15.6points) was similar to that found by Drake et al.3 (15.3 points)
andPerez-Chadaetal.7(15.7points).However,Perez-lloret
etal.17 found, in a study of 1194 13---17 year-olds of low
socioeconomiclevel,aslightlylowermeanPDSSscore(13.8 points).Additionally,Perez-lloretetal.17identifiedan
asso-ciationofEDSwithlowsleepduration,reducedattention, andpoorcognitiveperformance.Thus,consideringthemean scoresobserved intheaforementioned studies,aswell as theamplitudeofthescorescale(0---32points),itisbelieved that it is sensitive to assess EDS, as it does not have a ‘‘ceilingeffect’’and/or‘‘flooreffect’’inthesumof ques-tions.
Itisalsoobservedthatintheaforementionedstudiesthat usedthePDSS,includingitsvalidationstudy,cutoffpoints fortheclassificationofdifferentlevelsofEDSwerenot pro-posedasinEpworthscale,consideringthatthegreaterthe score,the higher theindication of daytime sleepiness.In thissense,theauthorssuggestcarryingoutfurtherstudies fortheproposedcutoffpointsforthesumofthescale.
Anotherkeypointreferstotherecommendedagerange fortheapplicationofPDSS.Theagerangeofchildrenand adolescentsintheoriginalvalidationstudybyDrakeetal.,3
11---15 yearsold,was expanded inthis study tomeet the assessmentneedsandduetothescarcityoftoolstoassess EDSinBrazilian children andadolescents.Moreover, liter-ature reports that EDS increases during adolescence due tobiologicaland environmentalfactors.8,9Thus,it is
con-sidered that the application of PDSS in children younger thantheageoftheoriginalscalevalidation(11years)must ensure the proper understanding of the questions, while for older ages (14 years), it is necessary toconsider the appropriateness of the scale regarding the sample profile orpatienttobeinvestigated.
Apossiblelimitationofthisstudyisthefactthatthe sam-plewasobtainedexclusivelyfromprivateschools.However, considering that the PDSS questions are easy to under-stand and directly related to the daily lives of children and adolescents, such a tool will be well understood by young individuals from other school networks. Addition-ally,thecorrelationbetweenPDSSscoreswithtimeinbed verified through the questionnaire may limit the analysis sensitivity.
Inviewofthepresentanalysis,PDSScanbeconsidered asvalidforapplicationinsamplesofBrazilianchildrenand adolescents,byshowing appropriateindicators ofvalidity, reproducibility,andinternalconsistency.
Conflicts
of
interest
Theauthorsdeclarenoconflictsofinterest.
Appendix
A.
Pediatric
Daytime
Sleepiness
Scale
(PDSS)
---
Brazilian
Portuguese
version
1.Comqualfrequênciavocêdormeousentesonoemsala deaula?
( )Sempre( )Frequentemente( )Àsvezes ( )Quasenunca( )Nunca
2.Comqualfrequênciavocêficacomsonoaofazeralic¸ão decasa?
( )Sempre( )Frequentemente( )Àsvezes ( )Quasenunca( )Nunca
3.Vocêestáatento/alertanamaiorpartedodia?a
( )Sempre( )Frequentemente( )Àsvezes ( )Quasenunca( )Nunca
4.Comqualfrequênciavocêsesentecansadoemal humoradoduranteodia?
( )Sempre( )Frequentemente( )Àsvezes ( )Quasenunca( )Nunca
5.Comqualfrequênciavocêtemdificuldadesparasairda camademanhã?
( )Sempre( )Frequentemente( )Àsvezes ( )Quasenunca( )Nunca
6.Comqualfrequênciavocêvoltaadormirdepoisde acordarpelamanhã?
( )Sempre( )Frequentemente( )Àsvezes ( )Quasenunca( )Nunca
7.Comqualfrequênciavocêprecisadealguémoude auxíliodedespertadorparateacordardemanhã? ( )Sempre( )Frequentemente( )Àsvezes ( )Quasenunca( )Nunca
8.Comquefrequênciavocêachaqueprecisadormirmais? ( )Sempre( )Frequentemente( )Àsvezes ( )Quasenunca( )Nunca
Pontuac¸ão:
Sempre=4
Frequentemente=3 Àsvezes=2 Quasenunca=1 Nunca=0
a Estaperguntapossuipontuac¸ãoreversa.
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