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  • ORIGINAL ARTICLE

    BRAZILIANPORTUGUESE VALIDATION OF THE UNIVERSITYOF WASHINGTON QUALITY OF LIFE QUESTIONNAIREFOR PATIENTS WITH HEAD AND NECK CANCER

    Jose Guilherme Vartanian, MD,1 Andre Lopes Carvalho, MD, PhD,1 Bevan Yueh, MD, MPH,2,3

    Cristina Lemos B. Furia, PhD,1 Julia Toyota, RN,1 Jennifer A. McDowell,2

    Ernest A. Weymuller Jr, MD,3 Luiz Paulo Kowalski, MD, PhD1

    1 Head and Neck Surgery and Otorhinolaryngology Department, Centro de Tratamento e Pesquisa Hospitaldo Cancer A. C. Camargo, Rua Professor Antonio Prudente, 211-01509-900 Sao Paulo, SP, Brazil.E-mail: lp_kowalski@uol.com.br2 Veterans Affairs Puget Sound Healthcare System, Seattle, Washington3 Department of Otolaryngology-Head and Neck Surgery, University of Washington, Seattle, Washington

    Accepted 11 April 2006Published online 5 July 2006 in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/hed.20464

    Abstract: Background. The University of Washington Quality

    of Life (UW-QOL) questionnaire is an English-language survey

    instrument used worldwide to assess the quality of life of patients

    with head and neck cancer. To be used in other cultures, such

    instruments require careful translation and psychometric valida-

    tion in other languages.

    Methods. The translation and cultural adaptation of the

    questionnaire were performed following accepted international

    guidelines. The psychometric validation was performed on a

    consecutive series of patients with at least 1 year of disease-free

    survival after treatment for squamous cell carcinoma of the

    upper aerodigestive tract, recruited from October 2004 to Janu-

    ary 2005 from a tertiary cancer center hospital. Eligible subjects

    were invited to complete the Portuguese version of the UW-QOL

    questionnaire during routine clinical consultation and complete it

    again within 15 days. They also completed a validated Portu-

    guese version of the Medical Outcomes Study 36-Item Short-

    Form Health Survey (SF-36) and a questionnaire to evaluate anx-

    iety and depression symptoms (Hospital Anxiety and Depres-

    sion Scale [HADS]).

    Results. A Portuguese version of the questionnaire was de-

    veloped in iterative fashion. In the psychometric validation proc-

    ess, a total of 109 patients were analyzed. Reliability was excel-

    lent, including both internal consistency (Cronbachs alpha [a] of0.744) and test retest reliability (intraclass correlation coefficient

    [ICC] of 0.882). Construct validity was supported by statistically

    significant relationships between the SF-36 and HAD question-

    naires and the translated UW-QOL questionnaire.

    Conclusions. The BrazilianPortuguese version of the UW-

    QOL questionnaire appears to be culturally appropriate and

    psychometrically valid. This version is a valuable tool to evaluate

    accurately the quality of life of Brazilian patients with head and

    neck cancer. VVC 2006 Wiley Periodicals, Inc. Head Neck 28:

    11151121, 2006

    Keywords: quality of life; head and neck cancer; questionnaires;

    validity; reliability

    During the past few years, quality of life (QOL)evaluation has been recognized as an importantoutcome measure in medicine, including oncol-ogy.1,2 These measurements have been made withregularity in the head and neck cancer popula-tion. QOL is important to assess because the mostrecent advances inmanagement can lead to differ-ent physical and/or functional sequelae.35 Theanatomic location of head and neck tumors may

    Correspondence to: L. P. Kowalski

    VVC 2006 Wiley Periodicals, Inc.

    Portuguese Version of UW-QOL Questionnaire HEAD & NECKDOI 10.1002/hed December 2006 1115

  • influence vital functions such as chewing, swal-lowing, and speech and may also impair cosmeticand psychosocial aspects of patients.6 In this con-text, evaluation of QOL is an important tool forunderstanding the impact of the head and neckcancer and its treatment on the patients life. Itcould also be a valuable tool for better planning oftreatment strategies.69

    Health-related QOL is usually measured byapplication of specific questionnaires. Among allquestionnaires designed to evaluate patients withhead and neck cancer, the University of Washing-ton Quality of Life (UW-QOL) questionnaire10 isone of the most frequently used worldwide. It iswell validated, concise, and easy to complete andinterpret. It has been very suitable for English-speaking populations. To introduce its use in othercultures and countries, it needs to be carefullytranslated and culturally adapted in the new lan-guage, and then psychometrically validated in thenew language, to guarantee its accuracy in thenew population.11,12

    The objective of this study was to perform thetranslation and psychometric validation of the UW-QOLquestionnaire into BrazilianPortuguese.

    MATERIALS AND METHODS

    The first step was the translation and adaptationof the UW-QOL questionnaire to the BrazilianPortuguese language.We followed internationallyaccepted guidelines.11,12 Two bicultural expertstranslated the original English version of the UW-QOL questionnaire to BrazilianPortuguese. Athird bicultural person performed the comparisonof the 2 versions and an iterative consensus wasreached. The consensus version of the BrazilianPortuguese translation was sent to other 2 addi-tional bicultural experts (at the University ofWashington, Seattle), who performed a similarback-translation process (from BrazilianPortu-guese to English). This back-translated versionwas then compared with the original English-lan-guage version to ensure that the translationsweresuitable. Discrepancies between the original andback-translated versions were resolved by repeat-ing the process as needed.

    The next step was the psychometric validation.We tested the translated version on a consecutiveseries of patients seen in the A. C. Camargo Hospi-tal outpatient clinic betweenOctober 2004 and Jan-uary 2005. Inclusion criteria were adult patientswith squamous cell carcinoma of the upper aerodi-gestive tractwho had 1 year of disease-free survival.Eligible patients were invited to participate in the

    study, and participants signed a consent formapproved by the Institutional Ethics Committee.

    All participants were asked to complete apacket of self-administered questionnaires duringthe routine outpatient clinic consultation and alsoreceived another UW-QOL questionnaire within 15days, which was returned by mail. The 15-dayinterval was chosen to measure testretest reli-ability, as enough time had elapsed to preventpatients from remembering their responses to thefirst administration of the scale, but not enoughtime to allow clinicallymeaningful change to occur.We emphasize that no patients in the study under-went treatment in this 15-day interim period. Thepacket included the following questionnaires:BrazilianPortuguese version of the UW-QOLquestionnaire, the BrazilianPortuguese validatedform of the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36),13 and the HospitalAnxiety andDepression Scale (HADS).14 The chartsof enrolled subjects were reviewed, and demo-graphic, tumor, and treatment datawere collected.

    Each domain item on the UW-QOL scale isscored from 0 to 100, with the composite scorebeing the mean of the 12 domains. A higher scoreis indicative of better QOL. Also, 3 separate globalquestions on overall QOL are not used in the com-posite score, and they can be analyzed separately.The HADS is a questionnaire consisting of 14questions designed to evaluate the presence ofanxiety and depression in patients with physicaldiseases. These 14 questions are divided in 2 sub-groups (7 questions to evaluate anxiety and 7 toevaluate depression), each question with scoresvarying from 0 to 3. The sum of each subscaledenotes the category of the patients: 0 to 7, non-cases; 8 to 10, doubtful cases; and 11 to 21 definitecases. In this study, we divided the HADS scoresin 2 categories: patients without depression(noncases) and those who may or definitely havedepression (doubtful and definite cases). TheSF-36 is a multidimensional, 36-item genericinstrument to evaluate QOL. Results may bereported in any of 8 subdomains, or as 2 summaryscores, termed the physical and mental compo-nent summary scales. These 2 component sum-mary scales describe general physical and mentalhealth. They are each scored from 0 to 100; ahigher score is indicative of better QOL, and ascore of 50 represents the normative value in theUS population.

    Reliability was established by assuring bothinternal consistency (Cronbachs a) and testre-test reliability (intraclass correlation coefficient

    1116 Portuguese Version of UW-QOL Questionnaire HEAD & NECKDOI 10.1002/hed December 2006

  • [ICC]) at 2 weeks in the absence of interim treat-ment. Internal consistency is considered good if aapproximates 0.70 but does not exceed 0.90,because values of 0.90 imply the presence ofredundant items.15 Testretest reliability wasmeasured with the ICC, which is more rigorousthan Pearsons correlation coefficient r because itconsiders not just the strength of the correlationbut also systematic variations.16

    There are 3 forms of validity: content, crite-rion, and construct. Content validity was estab-lished with the rigorous approach to item develop-ment in the original form. It is maintained by therigorous process of the translation and back-translation. The criterion validity, which testsscale performance in comparison to a gold stand-ard, is difficult to establish when evaluating QOLscales, mainly in head and neck cancer assess-ment because there is no instrument consideredgold-standard in this population. Construct va-lidity is present if the scale behaves according tohypothesized relationships. We hypothesized thatthe composite score of the UW-QOL should corre-late with general questions about overall QOLand themain component summary scales of the SF-36 questionnaire. We also hypothesized that higherdepression scores and larger tumors would result inworse UW-QOL scores. The Pearson correlationcoefficient andSpearman rho (q) were used to evalu-ate the correlations between continuous and ordinalvariables, respectively. The nonparametric tests ofMannWhitney or KruskalWallis were used tocomparemeans among the groups studied.

    The statistical analysis was performed usingversion 12.0 of the SPSS statistical program(SPSS, Chicago, IL) forWindows.

    RESULTS

    The first translation of the UW-QOL to BrazilianPortuguese was successful, without substantialdiscrepancies. A minor difficulty was encounteredin translating the word narcotics, which existsin Portuguese but is not currently used in Brazil.We opted to use the expression controlledmedica-tion, which is the term more commonly used inBrazil for the designation of such drugs. Afterotherminor adjustments, the back-translation wascompared with the original English version anddid not show any significant content discrepanciesbetween both versions. The final BrazilianPortu-guese version is contained in the Appendix.

    A total of 109 patients were enrolled in the psy-chometric validation process. Most were male

    (82.6%) with ages ranging from 34 to 83 years(median, 62 years). The tumor sites were: 37 oralcavity (33.9%), 19 oropharynx (17.4%), 39 larynx(35.8%), 11 hypopharynx (1.1%), and 3 nasopha-rynx (2.8%). The T classifications were as follows:51 (46.8%) T1/T2 and 58 (53.2%) T3/T4. Forty(36.7%) patients had surgery and radiotherapy, 30(27.5%) had surgery alone, 21 (19.3%) had radio-therapy alone, 14 (12.8%) had primary concomi-tant chemoradiation, and 4 (3.7%) had a combina-tion of surgery, radiation, and chemotherapy.

    The mean and standard deviation (SD) of theUW-QOL composite score in the test and retestevaluations were 80.2 (SD 12.6) and 78.9 (SD 13.9), respectively.

    The translated scale had strong internal consis-tency (Cronbachs a 0.744) and excellent testre-test reliability (ICC 0.880) (raw data inFigure 1).

    Construct validity was evaluated based on thehypotheses described. Patients with higher scoreson the depression scale had lower scores on theUW-QOL questionnaire, which showed a statisti-cally significant Spearmans q correlation of0.342(p < .001). This association was also significantwith dichotomous categorization of HADS scores asproposed by the authors (p < .001 [Figure 2]). TheUW-QOL composite scores behaved as predictedwhen patients were categorized by T classification,as patients with larger tumors had worse UW-QOLscores (p < .001) (Figure 3). The UW-QOL compos-ite scores also correlated well with global questions

    FIGURE 1. Testretest data of UW-QOL (ICC 0.880). ICC,intraclass correlation coefficient.

    Portuguese Version of UW-QOL Questionnaire HEAD & NECKDOI 10.1002/hed December 2006 1117

  • (Figure 4). There was also moderately strong con-cordance between the UW-QOL composite scoreand the Physical Component Summary (PCS) andMental Component Summary (MCS) scores of theSF-36 (Table 1).

    DISCUSSION

    QOL evaluation has become an important out-come measure in the head and neck cancer popu-

    lation during the past few decades.6,17 This impor-tance is highlighted by the potential impact ofsuch tumors and their treatment on functional,emotional, social, and professional aspects ofaffected individuals.10,18,19

    Typically, QOL is measured by the applicationof specific questionnaires. Most instruments havebeen designed in developed and English-speakingcountries.17,20,21 To be of use in other countriesand cultures, these scales require rigorous trans-lation and revalidation.11 The UW-QOL question-naire is a well-validated, concise, and minimallyburdensome scale,17 and also happens to be one ofthe most frequently used head and neck scales inthe world. We have successfully translated andadapted this scale for the Brazilian population.

    In addition, we have demonstrated that ourtranslation has excellent reliability and construct

    FIGURE 3. Graphic representation of the association between the

    UW-QOL composite score and the tumor T classification (p< .001).

    FIGURE 4. Graphic representation of the association between

    the UW-QOL composite score and the UW-QOL global question

    on overall quality of life (p < .001).

    Table 1. Correlation between UW-QOL composite score

    and the PCS and MCS scores from the Medical

    Outcomes Study SF-36.

    UW-QOL composite score SF-36 PCS SF-36 MCS

    Pearson 0.394 0.358

    Sig (1-tailed)

  • validity. We observed strong correlations betweenthe BrazilianPortuguese UW-QOL compositescores with T classification, global QOL, andHADS scores. Patients with poor overall QOL andlarger tumors, as well as patients with higherdepressive scores, had lower UW-QOL score, con-firming that the hypothesized variables that couldaffect the QOL were directly related to the UW-QOL scoring.

    An important consideration in the applicationof QOL scales is to understand what kind ofchange represents a minimally clinically impor-tant difference.22,23 As yet unpublished data fromthe University of Washington suggest that a 6- to8-point difference in the composite score is therange for a low to a high clinically important dif-ference (B.Y., 2003). Our Brazilian data suggestthat t...

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