Reliability of the Brazilian version of the PedsQL-ESDR questionnaire to evaluate quality of life of children and adolescents

A doença renal em estágio avançado (DREA) na infância tem apresentado incidência e prevalência crescentes na população pediátrica. Em 2008, a incidência Confiabilidade da tradução da versão brasileira do questionário PedsQL DREA para avaliação da qualidade de vida de crianças e adolescentes Reliability of the Brazilian version of the PedsQL ESDR questionnaire to evaluate quality of life of children and adolescents


IntroductIon
The incidence and prevalence of end-stage renal disease (ESRD) in children have increased.In 2008, the median global incidence of renal replacement therapy (RRT) in children and adolescents aged between zero and 19 years was four per million and 18 per million age-related population respectively, while prevalence ranged from 18 to 100 per million age-related population.According to the 2013 Census of the Brazilian Society of Nephrology, an estimated 100,000 patients were on dialysis nationwide, 0.4% of whom aged between one and 12 years. 1,2SRD is characterized by irreversible loss of renal function and decline in glomerular filtration rate to levels below 29 ml/min/1.73m 2 , followed by impairment of regulatory, excretory and endocrine function.The etiology of pediatric ESRD presents unique characteristics when compared to the disease in adults.The disease in children is based on congenital causes, with two thirds of the cases stemming from urinary system anomalies or inherited kidney disease.][3][4][5][6] Early diagnosis and adequate treatment are of paramount importance in delaying the progress of disease and ensuring good-quality patient survival.[9][10][11][12][13][14][15] In healthcare, QoL gained additional relevance when it was incorporated in the assessment of treatment outcomes, which led to the emergence of the idea of health-related quality of life (HRQoL).][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] In pediatric patients, HRQoL considers the difference between the expectations of patients and their families in regards to treatment -which may vary depending on individual expectations and past experiences with healthcare and illness.][35][36][37][38] The scales and instruments used to assess HRQoL must encompass multiple dimensions in order to capture an individual's perceptions over aspects concerned with QoL.Ideally, these scales should match the respondent's ability to understand and answer the questions in them, while providing useful information that may be reutilized in future interventions tailored to the specific needs of the patients as per the captured perceptions.The purpose of these scales, therefore, is to enable patients to share their impressions on the disease afflicting them. 17,20,22,30e Pediatric Quality of Life Inventory (Peds QL) TM 3.0 End-Stage Renal Disease (ESRD) module -Child/Adolescent Self-Report and Parent Proxy-Report was developed by Varni et al. to assess the HRQoL of patients with ESRD stages 4 and 5 as perceived by the patients themselves and their parents.This instrument looks into satisfaction with the treatment and allows insight into the patients' needs as per their own and their primary caregivers' views.In order for the Brazilian Portuguese version of the scale to be as effective and reliable as its original counterpart in English, it must undergo a thorough process of validation, which includes translation and cultural adaptation of the scale to the local reality. 18his paper aims to present the outcomes of the calculations carried out as part of the validation process of the Brazilian Portuguese version of the Peds QL TM

MAterIAls And Method
This study is part of the ongoing process of translating and linguistically adapting the Peds QL TM  The study enrolled children and adolescents aged between two and 18 years with ESRD stages 4 and 5 followed up in the Nephrology Unit of the Children's Institute at HCFMUSP and their respective primary caregivers.
The questionnaires were answered while patients and parents were at the Pediatric Nephrology Clinic or at the Dialysis Unit.Primary caregivers were first explained the purposes of the study and invited to join in.Those willing to participate were asked to give informed consent and were then interviewed for patient demographics and clinical data and PC demographics.The questionnaires were applied during outpatient visits or dialysis sessions.A researcher was present during most of the sessions to read the questions in the scale to the patients or to aid participants who answered the questions on their own and address comprehension issues.
The Peds QL TM 3.0 contains specific questionnaires for individuals in the 5-7, 8-12, and 13-18 year-old age groups, with 34 questions grouped into seven domains (General Fatigue, About My Kidney Disease, Treatment Problems, Family & Peer Interaction, Worry, Perceived Physical Appearance, and Communication) (Appendix 1). 18The parent proxy-report questionnaires are structured equally, but there is a specific set of 13 questions for children aged between two and four years grouped into four domains (General Fatigue, About My Kidney Disease, Treatment Problems, and Worry) (Appendix 2). 18he answers to each question are numbered from zero to four and converted into a score in which 0 = 100; 1 = 75; 2 = 50; 3 = 25; and 4 = 0. Domains with more than 50% of the questions left unanswered are not considered.While there is no cutoff point, scores close to 100 are deemed positive for QoL. 39

StatiStical analySiS
Sample size was calculated using software program StatsToDo and Cronbach's Alpha.The mean score in each domain was calculated by dividing the sum of the scores by the number of given answers.Cronbach's Alpha was also used in the separate comparison of mean domain scores and total scores.

results
Table 1 shows the demographic and clinical profiles of the interviewed patients (n = 24) in terms of age, gender, and treatment mode, in addition to relevant primary caregiver information (n = 32).
The final version of the translated scale was used in the interviews. 18None of the invited primary caregivers or patients refused to join the validation of the scale.All participants were able to comprehend and answer the questions in the scale.It took participants approximately five minutes to answer the questionnaire.In every domain, more than 50% of the questions were answered.
Table 2 shows the mean scores and the Cronbach's Alpha of the seven domains separately, as calculated from the reports, and the scores pertaining to all domains in the child/ adolescent self-reports and parent proxy-reports for each set of questionnaires.
Once the initial calculations yielded a Cronbach's Alpha under 0.50 for domains About My Kidney Disease and Treatment Problems in the child/adolescent self-reports and parent proxy-reports, the patients were regrouped into three age ranges (0-7; 8-12; 13-18 years) and their scores recalculated (Table 3).

dIscussIon
The scales currently used to assess the QoL of Brazilian pediatric patients were entirely developed abroad, particularly in Englishspeaking countries.9]30 The translation and ensuing cultural and linguistic validation of the Brazilian Portuguese Peds QL TM 3.0 scale used to assess the QoL of of the scale to a group of patients, proof reading, and final review. 18iven that the scale is used specifically to study individuals with ESRD at different stages of growth and development, statistical analysis was carried out in order to assess the sensitiveness of the scale when applied to Brazilian patients.Cronbach's Alpha was chosen to estimate the reliability of the scale for its track record with other similar scales and its use in the analysis of respondent answer profiles.
Despite the lack of agreement around a reference value for Cronbach's Alpha, some authors have considered 0.50 as appropriate, which was the case in almost every item analyzed in this study and in the global assessment of the questionnaires.These results have suggested the original scale is accurate and confirmed the use of the translated and adapted version.

FInAl consIderAtIons
The QoL of pediatric patients with ESRD must be assessed throughout the delivery of treatment.The availability of specific, regionally validated scales enhances patient QoL monitoring and allows for outcome comparisons between centers within the same region or from different areas of the globe, in addition to guiding the adoption of therapeutic measures.
This paper presented the validation process of a QoL assessment scale used with children and adolescents with ESRD, which proved valid, reliable, and useful in our setting.It is our hope that the pediatric nephrology community incorporates the scale into routine practice and that the expected refinement of the care provided to pediatric patients with ESRD materializes.
3.0 ESRD Module used to assess the QoL of children and adolescents with ESRD.
3.0 scale into Brazilian Portuguese for use in the assessment of HRQoL of Brazilian children and adolescents with ESRD.The main project was approved by the Research Ethics Committee of the University Hospital (HC) of the School of Medicine of the University of São Paulo (USP) and granted permit 0082/10.The MAPI Research Trust -the institution responsible for the original scale and all its versions -granted the study permission to carry out the translation, cultural adaptation, and validation of the scale.

tAble 2
DiStributiOn Of mean valueS anD crOnbach'S alpha fOr each DOmain anD peDS ql tm 3.0 eSrD mODule -

tAble 3
DiStributiOn Of crOnbach'S alpha On DOmainS abOut my kiDney DiSeaSe anD treatment prOblemS in the peDS qltm 3.0 eSrD mODule -chilD Self-repOrtS anD parent prOxy-repOrtS accOrDing tO age range things with my family because of my treatment 3. I feel left out of activities with my friends because of my treatment wOrry 1.I worry about whether or not my medical treatments are working 2. I worry about having surgery 3. I worry that I will be sick for a long time 4. I worry that I will have to stay in the hospital 5.I worry about my blood pressure 6.I worry that I will get sick if I don't take my medicines 7. I worry about my weight 8.I worry about getting infections 9.I worry about having needle sticks (i.e., injections, blood tests, IVs) 10.I worry about the results of my blood tests perceiveD phySical appearance 1.I don't like other people to see my scars2.I don't look as old as other kids my age 3. I am embarrassed that my medicines will change the way I look cOmmunicatiOn 1.It is hard for me to tell the doctors and nurses how I feel 2. It is hard for me to ask the doctors and nurses questions 3. It is hard for me to tell other people at the hospital (i.e., child life, dietician, social worker) how I feel 4. It is hard for me to explain my illness to other people 5.It is hard for me to tell my parents how I feel 1.It is difficult for me when other people don't understand about my illness 2. I can't do