Rev. Bras. Reumatol. vol.55 número5

rev bras reumatol.2015;55(5):398–405

w w w . r e u m a t o l o g i a . c o m . b r

REVISTA

BRASILEIRA

DE

REUMATOLOGIA

Original

article

Translation

and

cross-cultural

adaptation

of

FFI

to

Brazilian

Portuguese

version:

FFI

–

Brazil

夽

Liu

Chiao

Yi

,

Isabela

Maschk

Staboli

,

Danilo

Harudy

Kamonseki

,

Elly

Budiman-Mak

_,

_Eduardo

_Kenzo

_Arie

a_{InterdisciplinaryPost-GraduationPrograminHealthSciences,UniversidadeFederaldeSãoPaulo,Santos,SP,Brazil} b_{PhysiotherapyCourse,UniversidadeFederaldeSãoPaulo,Santos,SP,Brazil}

c_{MedicineDepartment,LoyolaUniversityofChicago,Chicago,UnitedStates} d_{SantaCasadeSantos,Santos,SP,Brazil}

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Articlehistory: Received17May2014 Accepted9November2014 Availableonline18March2015

Keywords: Function Questionnaire Translation Foot

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Objective:PerformthetranslationandculturaladaptationofthequestionnaireFoot Func-tionalIndex(FFI),whichassessesthefunctionalityofthefoot,totheBrazilianPortuguese version.

Method:TheBrazilianversiondevelopmentofFFIquestionnairewasbasedontheguideline proposedbyGuillemin.Theappliedprocessconsistedof:(1)translation;(2)back-translation; (3)committeereview;(4)pretesting.ThePortugueseversionwasappliedto40patients,both genders,agedover18yearsold,withplantarfasciitisandmetatarsalgiatoverifythelevelof theinstrumentcomprehension.ThefinalBrazilianversionoftheFFIwassetaftergetting lessthan15%of“notunderstanding”oneachitem.

Results:SometermsandexpressionswerechangedtoobtainculturalequivalenceforFFI. Thetermsthatwereincomprehensiblewerechangedinaccordanceofpatientsuggestions. Conclusion:Afterthetranslationandculturaladaptationofthequestionnaire,thefinal Por-tugueseversionofFFIwasconcluded.

©2015ElsevierEditoraLtda.Allrightsreserved.

Traduc¸ão

e

adaptac¸ão

cultural

do

Foot

Function

Index

para

a

língua

portuguesa:

FFI

–

Brasil

Palavras-chave: Func¸ão Questionário Traduc¸ão Pé

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Objetivo:Fazeratraduc¸ãoeaadaptac¸ãoculturaldoquestionárioFootFunctionalIndex(FFI), queavaliaafuncionalidadedopé,paraaversãoemlínguaportuguesadoBrasil.

Métodos:A versão brasileira do FFI foi baseada no protocolo proposto por Guillemin.8 Oprocesso aplicadoconsistiuem:(1)traduc¸ão;(2) retrotraduc¸ão;(3) análisedocomitê deespecialistas;(4) pré-teste.Aversãobrasileirafoi aplicadaem40pessoas,homense

夽

WorkconductedwiththehelpoftheinstitutionalProgramofScientificInitiationscholarships(PIBIC/CNPq). ∗ _{Correspondingauthor.}

E-mail:liuchiaoyi@yahoo.com.br(L.C.Yi).

http://dx.doi.org/10.1016/j.rbre.2014.11.005

rev bras reumatol.2015;55(5):398–405

399

mulherescomidadesuperiora18anos,comfasciíteplantaremetatarsalgia,paraverificar oníveldecompreensãodoinstrumento.Aversãofinalfoidefinidaapósseobtermenosde 15%de“nãocompreensão”emcadaitem.

Resultados: ForamalteradostermoseexpressõesparaobterequivalênciaculturaldoFFI.As alterac¸õesfeitasforambaseadasnassugestõesdospacientes.

Conclusão: Apósatraduc¸ãoeadaptac¸ãoculturaldoquestionário,foiconcluídaaversãoda línguaportuguesadoBrasildoFFI.

©2015ElsevierEditoraLtda.Todososdireitosreservados.

Introduction

Inrecentyearstherehavebeenchangesintheapproachof musculoskeletaldisorders.Inthepast,clinicalchangeswere assessedbyphysicalexaminationandlaboratorytests. Cur-rently,outcomessuchasfunctionalityhavebeenemphasized astheyallowforananalysisofthehealthsituation,theimpact ofdiseasesonpatient’slife,andprovidethenecessary infor-mationtoevaluatetheeffectivenessofdifferenttreatments.

Thus,evaluationmeasuresthatmeasurefunctional,social andemotionalaspectshavebeenproposed,whichcanbeused bothinclinicalpracticeandinresearch.1–4

Inorder toapplyhealthevaluationmeasures,developed andusedinanotherlanguage,across-culturalequivalenceis necessary.Thisprocessconsistsonthetranslation,cultural adaptation and evaluation of the psychometric properties of the instrument. The translation and cultural adapta-tion phase allows the adjustment of the instrument to the new language, population, environment and culture. Psychometricpropertiesassessmentphases(validity, repro-ducibility and sensitivity to changes) consistson checking whetherthenewversionretainedthefeaturesoftheoriginal design.5–9

Musculoskeletal injuries in distal lower limbs causes several complications such as functional limitations and impairedqualityoflife.Approximately4%oftheworld popu-lationbetween25and74yearsarelikelytodevelopdiseases intheankleandfoot.2_{Therefore,instrumentshavebeen} pro-posedtoassesstheimpactonqualityoflifeandeffectiveness ofdifferenttreatments.1

Evaluation instruments of ankle and foot disorders are mainlyavailableinEnglishlanguage.Amongthem,theFFI (FootFunctionIndex),AOFAS(AmericanOrthopaedicFootandAnkle Society),FAOS(Foot andAnkleOutcomeScore),WOMAC (West-ernOntarioandMcMasterUniversitiesOsteoarthritisIndex),LFIS (LeedsFootImpactScale)andMFPDQ(ManchesterFootPainand DisabilityQuestionnaire).

FFI (Foot Function Index) is a questionnaire developed in Englishtoevaluatefootfunctioninpatientswhohave muscu-loskeletalinjuries.Sinceevaluationisfocusedonthefoot,the questionnairehasgreateraccuracyandsensitivityfor identi-fyingchangesinthisarea,whencomparedtootheravailable instruments.2 _{In assessing the reproducibility of the} origi-nalFFI,theintraclasscorrelationcoefficientwasconsidered excellent.2

FFItranslations and validationshavealreadybeen done intoChinese,4_German,5_French6_anItalian.7_{Thisstudyaimed}

attranslatingandmakingtheculturaladaptationoftheFFI questionnairetoBrazilianPortuguese.

Materials

and

methods

Participants

Fortypatientsparticipatedinthestudy,withclinical diagno-sisofplantarfasciitisandmetatarsalgia.Themeanagewas33 yearsand78%werefemale.Regardingthelevelofeducation, 42%hadnotcompletedtertiaryeducation,32%completed ter-tiaryeducation,24%completedsecondaryeducation,and2% didnotcompletesecondaryeducation.

ThestudywasapprovedbytheResearchEthicsCommittee n.226.521andanauthorizationfromtheauthoroftheFFIwas obtainedviaelectronicmailforitsuse.

Procedures

TheBrazilian versionofFFI was obtainedaccordingto the guidelineproposedbyGuillemin8_(Fig.1).

FFIwasinitiallytranslatedbytwoindependenttranslators who had Portugueseasa native language. Thus two inde-pendentversions,V1andV2,wereobtained.Then,thetwo translationswerecomparedanddiscussedbythetranslators andmembersofthecommitteeconsistingofthree physiother-apistsspecializedintraumatologyand orthopedics,andan orthopedistspecializedonankleandfootresearch.This meet-ing resultedina consensusversion,V3,which maintained the fundamental characteristics of the original question-naire.

V3versionwastranslatedbackintoEnglishbytwonative English-speaking translators,formingtwoindependent ver-sions(V4andV5),andthetranslatorsdidnothaveaccessto the originalquestionnaire.Then,the membersofthe com-mitteemetagain,todiscussthedifferencesbetweenversions (V1,V2,V3,V4andV5)andtheoriginalquestionnaire. Sen-tencesthatrequiredmodificationshadbeenrewritteninorder toimprovethesemantic,idiomatic,culturalandconceptual equivalence,andtheV6versionwasobtained.

400

Preparation

Initial translation

V2

First version in Portuguese V3

Back-translation

Committee analysis original version +V1+V2+V3+V4+V5

Committee analysis V1

V5

V6 Pretest (reformulation)

Sent to FFI author Final version in Portuguese V7

V4

Fig.1–Studyflowchart.

Eachitemofthequestionnairewasreadaloudforthe par-ticipants,who hadto:(1)answeriftheyunderstood(yesor no);(2) commentwhat theyunderstoodofeach itemread; and (3)suggest changes if therewere any itemsthat were “notunderstood”.Accordingtotheresultsofthisstage,some terms hadbeen adaptedand modified. Afterthis step,the questionnairewasadministered to20patients inasecond phase of Cognitive Interviews to refine clarity and under-standingoftheinstrument,anditemswithmorethan15% of “no understanding” were reformulated by the commit-tee.

Again, thisversion wasanalyzed bythecommitteeand senttotheauthorofFFIforapproval, resultinginthefinal versionV7(Fig.2).

Scorecalculation

Forthetotalscoreofeachdomain,thefollowingformulawas applied:sumofthescoreobtainedfromallitemsanswered bythe patient/totalscorepossible ofthedomain x 100, in ordertogetthevalueinpercent.Ifthepatientdoesnot per-formanactivitymentionedinoneoftheitems(e.g.nouseof assistivedevices),thisisconsiderednotapplicable.Thus,the scoreoftheseitemsarenotconsideredinthetotalsumofthat domain.

The final percentage of all domains shall be summed anddividedbythree(totalnumberofdomains)thus obtain-ing the final result of the questionnaire. The results may vary from 0 to 100% and are directly proportional to the limb functional impairment, and the higher the percent-age, the greater the functional change presented by the patient.2

Results

Atthetranslationphase,somechangestookplaceduringthe committeemeeting, whenall itemsofV1 and V2 versions werediscussedfortheformulationofconsensusversionV3 (Table1).

Afterback-translationthecommitteemetagaintodiscuss thedifferencesbetweenallversions(V1,V2,V3,V4andV5)and theoriginalquestionnaire.Atthisstage,changesweremade ingrammaticalstructuresofsomeitemsforequivalenceof words,languages,andadaptationofculturalcontext(Table2). Regarding the pre-test, the items “not understood” and changedduringthephasesofcognitiveinterviewareincluded inTable3.

In thefirst phaseofthe Cognitive Interviewstwoitems of the FFI questionnaire, the numerical scale of 10 scores and item C1 in the worst pain crisis were reformulated, dueto“nounderstanding”bymorethan15%ofpatients.In thesecond stageofcognitiveexamination,patientsdidnot showdifficultiesinunderstandingtheitems.Sotherewasno changes.

Withthe pre-testperformedand thenecessary changes made,thefinalversionofPortugueseFFIwasdefined(V7).This versionwassenttotheauthoroftheoriginalversionofFFI, whodidnotsuggestanychanges.

Discussion

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Nome: Identifícação do paciente: Data:

Patologia do pé: Idade:

Escala numérica de dor: 0 1 2 3 4 5 6 7 8 9 10

Dor no pé e índice de incapacidade:

Incapacidade

Pontuação

Exemplo: Por quanto tempo você:

A. Por quanto tempo você:

0. Anada pela casa de sapatos: Nunca

Pontuação/

NA

0 1 2 3 4 5 6 7 8 9 Sempre /

1. Usa bengala, muletas ou andador dentro de casa?

2. Usa bengala, muletas ou andador fora de casa?

3. Fica em casa a maior parte do dia devido a problemas no pé?

4. Fica na cama a maior parte do dia devido a problemas no pé?

5. Limita suas atividades devido a problemas no pé?

A escala numérica de cada item abaixo representa com que frequência você fez cada atividade na última semana. A extremidade esquerda dos números representa nunca e a direita sempre. Faça uma marca no número que indica com que frequência você conseguiu realizar as atividades na última semana por causa de seus pés. Caso você não tenha realizado a atividade na última semana marque NA (não se aplica) àextrema direita do item.

Nível de escolaridade:

Nunca 0 1 2 3 4 5 6 7 8 9 Sempre /

Nunca 0 1 2 3 4 5 6 7 8 9 Sempre /

Nunca 0 1 2 3 4 5 6 7 8 9 Sempre /

Nunca 0 1 2 3 4 5 6 7 8 9 Sempre /

Nunca

Total /Possível = %

0 1 2 3 4 5 6 7 8 9 Sempre /

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B. Quanta dificuldade você teve para:

Pontuação/

NA

1. Andar pela casa?

A escala numérica de cada item abaixo representa quanta dificuldade você teve quando realizou estas atividades na última. A extremidade esquerda dos números

representa nenhuma dificuldade e a direita tanta dificuldade que não foi possível realizar. Faça uma marca no número que indica a dificuldade

que você

teve para realizar as atividades na última semana por causa de seus pés. Caso você não tenha realizado a atividade na última semana marque NA

(não se aplica) à extrema direita do item.

Nenuma dificuldade 0 1 2 3 4 5 6 7 8 9 Muita dificuldade/

Impossível

2. Andar fora de casa no solo irregular? Nenuma dificuldade 0 1 2 3 4 5 6 7 8 9 Muita dificuldade/ Impossível

3. Andar quarto quarteirões ou mais? Nenuma dificuldade 0 1 2 3 4 5 6 7 8 9 Muita dificuldade/ Impossível

4. Subir escadas? Nenuma dificuldade 0 1 2 3 4 5 6 7 8 9 Muita dificuldade/

Impossível

5. Descer escadas? Nenuma dificuldade 0 1 2 3 4 5 6 7 8 9 Muita dificuldade/

Impossível

6. Ficar na ponta dos pés? Nenuma dificuldade 0 1 2 3 4 5 6 7 8 9 Muita dificuldade/

Impossível

7. Levantar da cadeira? Nenuma dificuldade 0 1 2 3 4 5 6 7 8 9 Muita dificuldade/

Impossível

8. Subir ou descer calçadas? Nenuma dificuldade 0 1 2 3 4 5 6 7 8 9 Muita dificuldade/

Impossível

9. Andar rápida ou correr? Nenuma dificuldade 0 1 2 3 4 5 6 7 8 9 Muita dificuldade/

Impossível

Total /Possível = %

Dificuldade

Pontuação

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403

B. Quanta dificuldade você teve para:

Pontuação/

NA

1. Na pior crise de dor?

A escala numérica de cada item abaixo representa o nível de dor que você sentiu em cada situação. A extremidade esquerda dos números represnta sem dor e a direita a pior dor imaginável. Faça uma marca no número que indica a intensidade da dor nos seus pés quando realizou essas atividades na última semana. Caso você tenha realizado a atividade na última semana marque NA (não se aplica) à extrema direita do item.

Sem dir 0 1 2 3 4 5 6 7 8 9 A pior dor imaginável

2. Antes de se levantar pela manhã? Sem dir 0 1 2 3 4 5 6 7 8 9 A pior dor imaginável

3. Quando anda descalço? Sem dir 0 1 2 3 4 5 6 7 8 9 A pior dor imaginável

4. Quando fica em pé descalço? Sem dir 0 1 2 3 4 5 6 7 8 9 A pior dor imaginável

5. Quando anda calçado? Sem dir 0 1 2 3 4 5 6 7 8 9 A pior dor imaginável

6. Quando fica em pé calçado? Sem dir 0 1 2 3 4 5 6 7 8 9 A pior dor imaginável

7. Quando anda usando aparelho ortopédico? Sem dir 0 1 2 3 4 5 6 7 8 9 A pior dor imaginável

8. Quando fica em pé usando aparelho ortopédico? Sem dir 0 1 2 3 4 5 6 7 8 9 A pior dor imaginável

9. Ao final do dia? Sem dir 0 1 2 3 4 5 6 7 8 9 A pior dor imaginável

Total /Possível = %

Dor

Pontuação

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Table1–Modificationontheinitialphaseoftranslation.

QuestionnaireItem V1andV2 ModificationforconsensualversionV3

A.Footpainanddisabilityindex V1Índicededornopéeincapacidade Dornopéeíndicedeincapacidade V2Dornopéeíndicedeimobilidade

A.Noneoftime V1Nenhumapartedotempo Nunca

V2Nunca

A.Disability V1Imobilidade Incapacidade

V2Incapacidade

A3.Stay V1Fica Fica

V2Permanece

B2.Unevenground V1Pisoirregular Soloirregular

V2Soloirregular

B9.Walkfast V1Andardepressa Andarrápido

V2Andarrápido

C1.Atitsworst V1Quandodóimais Napiordor

V2Napiordashipóteses

C5.Wearingshoes V1Calc¸andosapatos Calc¸ado

V2Usandosapatos

C7.Wearingorthotics V1Usandoaparelhoortopédico Usandoaparelhoortopédico

V2Usandopalmilhaortopédica

C.Worstpainimaginable V1Apiordorimaginável Apiordorimaginável

V2Piordorquesentiu

V1,versioninPortuguesebythefirsttranslator;V2,versioninPortuguesebythesecondtranslator;V3,consensualversioninPortuguesedefined attheendoftheinitialphaseoftranslation.

Table2–Phaseofback-translation.Modificationsin“V4”and“V5”fordefinitionof“V6”.

V4andV5.QuestionnaireItem-Term V6.QuestionnaireItem-Term

B8.V4Subiroudescernacalc¸ada? B8.Subiroudescercalc¸adas?

V5Subiroudescercalc¸adas?

C1.V4Quandodóimais? C1.Napiordor?

V5Quandodóimais?

C5.V4Quandoandacomcalc¸ado? C5.Quandoandacalc¸ado?

V5Quandovocêandacomcalc¸ado?

C6:V4Quandovocêestáparadaempécomcalc¸ado? C6.Quandoficaempécalc¸ado?

V5Quandovocêestáempécomcalc¸ado?

V4andV5,versionsinPortugueseoftheback-translationphase;V6,versiondefinedinPortugueseafteranalysisofalltranslatedversionsand originalversionofthequestionnaire.

Theprocedure oftranslation and culturaladaptation of instrumentsproposedbyGuillemin8 _{hasbeenfollowedand} citedinseveralstudies,duetointernationalrecognizement criteria.Thereareseveralquestionnairesalreadytranslated andvalidatedintheliteraturethatfollowedthisprocedure,as WOMAC(WesternOntarioandMcMasterUniversities)9_andFAOS (FootandAnkleOutcomeScore).10_{Thus,thesameprocedurewas} followedfortheFFIquestionnaire.

IntheinitialphaseofFFItranslationintoPortuguese,some expressionswerechangedbythecommittee.Amongthem, thequestionA.(“Disability”)wasthemostdistinctexpression amongtranslators,inwhichoneofthetranslatorsinterpreted as immobility(Imobilidade) and the other as lackof capac-ity(Incapacidade).Atconsensus,thecommitteedecidedthat the most appropriateterm would be Incapacidade. In back-translation,thequestionsthatweremostdiscussedwiththe

Table3–Pretest:cognitiveinterviews.

Notunderstooditems Patients(%) Suggestions

1stphaseoftheCognitiveInterviews(n=20)

VisualAnalogScale 14(70%) NumeralScaleof10points

C1.Atworstpain? 11(55%) C1.Atworstpaincrisis?

C7.Whenwearorthotics? 1(5%) C7.Incaseyouwearorthotics,whenyouwalk

wearingorthotics?

2ndphaseoftheCognitiveInterviews(n=20)

Noitems“notunderstood” Nochanges

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committeemembersinordertoreachaconsensuswere ques-tionsC1.“Quandodoimais(Whenisyourpainmoresevere)?” and C5. “Quandoanda com calc¸ado (When you walk with shoes)?”,whichweremodifiedto“Napiordor(Attheworst pain)?”and“Quandoandacalc¸ado(Whenyouwalkedwearing shoes)?”,respectively.

At pretest phase (Cognitive Interviews phase), changes insomeitemswere suggestedforthebetterunderstanding ofthe patients.Thechanges made inthe firstphase were relatedtotheVisualAnalogScale(alineof10cmisarranged betweenthenumbersofthetwoextremes0and10)andthe item C1. “At worst pain?”,which were suggestedby more than15%ofpatients,beingmodifiedto:interspersed Numer-icalScalesfrom1to10pointsand“Napiorcrisededor(At theworstpaincrisis)?”.ItemC7“Quandoandausando apar-elho ortopédico (When you walk wearing orthotics)?” was suggestedtobechangedbyonly5%ofpatients,not reach-ing 15% to be rewritten. After the changes,there was no needtochange anything inthe second phaseofCognitive Interviews.

Inthe present study,plantar fasciitis and metatarsalgia wereselectedbecausetheyare chronicdiseasesthataffect mostlythe feet.Astheyaffect mainlywomen, this gender prevailedinthestudy.AllapplicationsofFFIwereconducted throughinterviews,basedonpreviousstudieswiththesame purpose.9,10

Althoughtherearemethodologicalvariationsofthe pro-cessoftranslationandculturaladaptationofquestionnaires aboutqualityoflifeandfunctionality,thestandardprocess mustbemaintained,includingthephasesoftranslation,back translationandculturaladaptation.11–13_{TheBrazilianversion} ofFFI isinprocess ofpsychometricspropertiesevaluation. Afterthe end ofthe process it will beavailablefor use in Brazil.

Conclusion

TheprocessoftranslationandculturaladaptationoftheFFI wascarriedoutandtheversiontoBrazilianPortuguesewas obtained.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

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