Applying the Principles of Good Research Practice For Cross-Cultural Adaptation to Pediatric Health-Related Quality of Life Questionnaires

Abstract

Although still debated about its definition and conceptualization, the healthrelated quality of life (HRQOL) concept is simply defined as the patient’s evaluation of the impact of a health condition and its treatment on daily life. HRQOL is a multidimensional construct that covers physical, emotional, mental, social, and behavioral components of well-being and functioning. HRQOL is possible to conceptualize through objective indicators. A great deal of attention has been paid to ensure reliable and valid HRQOL measurements through the development of questionnaires with sound psychometric properties.

Continually from the past decade, HRQOL is more frequently used in prevention, treatment, and rehabilitation both, nationally and internationally. This requires that HRQOL measures are available across different nations/languages. With this in mind, questionnaires with good psychometric properties need to be simultaneously developed across different nations and cultures or, a slightly different but equally successful approach, the translation, subsequent analysis, and adaptation of existing and accepted measures into other languages is performed while considering aspects of the cultural settings. So far, cross-cultural adaptation of questionnaires has been recognized as one of the priority in HRQOL research.

It is early recognized that HRQOL assessments have some specific characteristics when children and adolescents are considered. The development of pediatric HRQOL measurement followed specific pathways with several important issues: specific HRQOL domains, age and developmental characteristics, self- and proxy-rating, generic and disease specific approaches to assessments, and psychometric considerations. Up to date, no clear guidelines for the cross-cultural adaptation of pediatric HRQOL questionnaires were developed. The aim of this thesis was to operationalize a model of the cross-cultural adaptation of pediatric HRQOL questionnaires.Taking a systematic approach, the cross-cultural adaptation process was described as should be followed for pediatric HRQOL questionnaires - including the procedures of translation and cultural adaptation, pretesting, psychometric evaluation, and assessing equivalence with bias elimination.

The operational model of the cross-cultural adaptation process for pediatric HRQOL questionnaires was developed following the previously established guidelines for translation and cultural adaptation, psychometric evaluation, and equivalence testing with bias elimination. The operational model has five consecutive phases: pre-translation, translation, pre-testing, psychometric, and finalization phase. Within the cross-cultural adaptation model, five aspects of investigating equivalence are recognized to claim levels of equivalence achievement: conceptual, semantic, items, operational, and psychometric. The operational model was presented considering four generic and two epilepsy specific questionnaires: KINDL questionnaire, KIDSCREEN questionnaire, Pediatric Quality of Life Inventory Version 4.0 Generic Core Scales - PedsQL, Quality of Life Enjoyment and Satisfaction Questionnaire Short form-Q-LES-Q-SF, Health- Related Quality of Life Measure for Children with Epilepsy - CEQOL-25, and Quality of Life in Epilepsy Inventory for Adolescents - QOLIE-AD-48.

The cross-cultural adaptation process of a HRQOL questionnaire to a new language/culture is a complex process involving several consecutive steps in order to ensure that the HRQOL concept represented by the questionnaire is appropriately transferred to that new language/culture. The essence of the process actually involves weighting between the altering of the source questionnaire’s items literally (i.e. translation) and removing, changing, adding, supplementing and/or modifying those items that deal with behavior that does not generalize equivalently in the target culture (i.e. cultural adaptation). Qualitative evaluations(i.e. pre-testing) and quantitative evaluations of the target questionnaires (i.e.psychometric evaluations) are added to confirm that the measuring concept represented by the questionnaire is appropriately transferred to the target culture/language.

Alternate abstract:

Iako se još uvek debatuje o definiciji i konceptu, kvalitet života povezan sa zdravljem (eng. health-related quality of life - HRQOL) bi jednostavno označavao kako pacijent procenjuje uticaj svog zdravstvenog stanja i primenjenih tretmana na svakodnevni život. Ovo je multidimenzionalni konstrukt, koji uključuje fizičke, emocionalne, mentalne, i socijalne komponente blagostanja i funkcionisanja pacijenta. Kao subjektivini pojam, HRQOL je moguće shvatati kroz objektivne indikatore i kroz kvalitativne i kvantitativne procene. Tokom poslednje dve decenije, posebna pažnja je posvećena obezbeđivanju pouzdanih i validinih procena HRQOL, kroz razvoj upitnika, koji imaju dobre psihometrijske osobine.

HRQOL se učestalo istražuje u prevenciji, lečenju i rehabilitaciji različitih poremećaja kako nacionalno tako i internacionalno, što zahteva da su upitnici dostupni za više jezika/nacija. Imajući ovo u vidu, HRQOL upitnici sa dobrim psihometrijskim karakteristikama moraju biti razvijeni simultano kroz više kultura/nacija ili da se prevode i adaptiraju već postojeći upitnici poštujući kulturološke odlike jezika na koji se prevode. Na ovaj način, unakrsna kulturološka adaptacija upitnika je prepoznata kao jedan od prioriteta u HRQOL istraživanjima.

Procena HRQOL kod dece i adolescenata ima određene specifičnosti, na primer HRQOL domeni specifični samo za ovu populaciju, godine i razvojne karakteristike, samo-procna i proksi-procena, generički i specifični upitnici, kao i psihometrijske odlike. Međutim, ne postoje jasne smernice za prevod i kulturološku adaptaciju pedijatrijskih upitnika za HRQOL. Cilj ove teze je da se koncipira model za kulturološku adaptaciju pedijatrisjkih upitnika. Pristupajući na sistematičan način procesu kulturološke adaptacije HRQOL upitnika predloženo je nekoliko procedura: prevod, kulturološka adaptacija, pre-testiranje, psihometrijska evaluacija, uz procenu nivoa slaganja originalnog i prevedenog upitnika (ekvivalentnost upitnika). Operativni model za kulturološku adaptaciju pedijatrijskih upitnika za HRQOL je razvijen usvajanjem postojećih vodiča i preporuka za prevod i kulturološku adaptaciju, psihometrijsku evaluaciju i procenu ekvivalentnosti raznih upitnika.Model ima pet konsekutivnih faza:procesi pre prevoda, sam prevod, pre-testiranje, psihometrijska procena ifinalizacija prevoda. Pet aspekata procene ekvivalentnosti upitnika su izdvajena:konceptualna, sematička, pitanja, operacionalna i psihometrijska. Operativnimodel je predstavljen na četiri generička i dva upitnika specifična za epilepsiju:KINDL, KIDSCREEN, Pediatric Quality of Life Inventory Version 4.0 Scales –PedsQL, Quality of Life Enjoyment and Satisfaction Questionnaire Short form – QLES-Q – SF, Health-Related Quality of Life Measure for Children with Epilepsy -CEQOL-25, i Quality of Life in Epilepsy Inventory for Adolescents - QOLIE-AD-48.

Proces kulturološke adaptacije HRQOL upitnika za decu i mlade na drugilezik je složen process, koji uključuje niz konsekutivnih koraka kojim seobezbeđuje da HRQOL koncept koji je u osnovi originalnog upitnika budeadekvatno “prenet” na novu verziju, to jest drugi jezik. Suštinu procesa činiodmeravanje između “literarnog preuređivanja” i menjanja, adaptiranja, dodavanjai/ili modifikovanja pitanja, naročito onih koja se odnose na ponašanja koja nisuprisutna u kulturi na koju se upitnik prevodi Kvalitativna (pre-testiranje) ikvantitativna (psihometrijsko testiranje) procena prevoda upitnika su sledećikoraci, kojim se dodatno obezbeđuje da je HRQOL koncept koji se meri određenimupitnikom zaista prenet na novi jezik. Operativni model kulturološke adaptacijeupitnika koji je usvojen u ovoj tezi pruža nove mogućnosti i izazove za istraživanjeHRQOL u pedijatrijskim populacijama. Međutim, na prvom mestu, važno je da seproceni važnost predloženih koraka u fazama kulturološke adaptacije kroz studijepraćenja, koje bi procenjivale navedene korake na različite načine. Takođe, važnobi bilo razviti smernice koje bi bile konsenzualno donete o kulturološkoj adaptacijiupitnika o kavalitetu života, ali i drugih koji se odnose na procenu ishoda lečenja.