Development of the Brazilian Portuguese version of the Achilles Tendon Total Rupture Score (ATRS BrP): a cross-cultural adaptation with reliability and construct validity evaluation

Zambelli et al. BMC Sports Science, Medicine and Rehabilitation (2016) 8:11 DOI 10.1186/s13102-016-0034-0 RESEARCH ARTICLE Open Access Development of the Brazilian Portuguese version of the Achilles Tendon Total Rupture Score (ATRS BrP): a cross-cultural adaptation with reliability and construct validity evaluation Roberto Zambelli1, Rafael Z. Pinto2,3, João Murilo Brandão Magalhães1, Fernando Araujo Silva Lopes1, Rodrigo Simões Castilho1, Daniel Baumfeld4, Thiago Ribeiro Teles dos Santos5 and Nicola Maffulli6,7* Abstract Background: There is a need for a patient-relevant instrument to evaluate outcome after treatment in patients with a total Achilles tendon rupture. The purpose of this study was to undertake a cross-cultural adaptation of the Achilles Tendon Total Rupture Score (ATRS) into Brazilian Portuguese, determining the test-retest reliability and construct validity of the instrument. Methods: A five-step approach was used in the cross-cultural adaptation process: initial translation (two bilingual Brazilian translators), synthesis of translation, back-translation (two native English language translators), consensus version and evaluation (expert committee), and testing phase. A total of 46 patients were recruited to evaluate the test-retest reproducibility and construct validity of the Brazilian Portuguese version of the ATRS. Test-retest reproducibility was performed by assessing each participant on two separate occasions. The construct validity was determined by the correlation index between the ATRS and the Orthopedic American Foot and Ankle Society (AOFAS) questionnaires. Results: The final version of the Brazilian Portuguese ATRS had the same number of questions as the original ATRS. For the reliability analysis, an ICC(2,1) of 0.93 (95 % CI: 0.88 to 0.96) with SEM of 1.56 points and MDC of 4.32 was observed, indicating excellent reliability. The construct validity showed excellent correlation with R = 0.76 (95 % CI: 0.52 to 0.89, P < 0.001). Conclusion: The ATRS was successfully cross-culturally validated into Brazilian Portuguese. This version was a reliable and valid measure of function in patients who suffered complete rupture of the Achilles Tendon. Keywords: Achilles Tendon Total Rupture Score (ATRS), Complete rupture of the Achilles Tendon, Functional questionnaires, Cross-cultural adaptation * Correspondence: 6 Department of Musculoskeletal Disorders, University of Salerno School of Medicine and Surgery, Salerno, Italy 7 Centre for Sports and Exercise Medicine, Queen Mary University, Mile End Hospital, London, UK Full list of author information is available at the end of the article © 2016 Zambelli et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Zambelli et al. BMC Sports Science, Medicine and Rehabilitation (2016) 8:11 Background The use of patient-reported questionnaires to estimate functional capacity, pain and limitation in activities of daily living is an important outcome measure to monitor treatment progress in clinical and research settings [1]. The Knee Injury and Osteoarthritis Outcome Score (KOOS) [2] and the Foot and Ankle Outcome Score (FAOS) [3] are examples of patient-reported questionnaires widely used to assess perceived activity limitations in patients with osteoarthritis of the knee and patients with ankle ligament injury respectively. With increasing number of publications from different countries, crosscultural adaptation of patient-reported questionnaires is essential when the aim is to compare the results of interventions across different populations [4, 5]. Ruptures of the Achilles tendon are relatively common in adults, especially in individuals aged 30–50 years. Men are three to four times more likely to sustain an injury than women [6–8]. The incidence has been reported to vary between 9.9 to 37.3 cases per 100,000 people [6, 9]. The recent increase in incidence has been associated with increased participation in high demand competitive and recreational sports, aging population, lack of fitness and performing strenuous physical activities [10–12]. Another explanation may be the increasing incidence of metabolic and other chronic diseases, which are associated with acute Achilles tendon ruptures [13]. An important tool for evaluation of patients who have suffered a complete rupture of the Achilles tendon is the Achilles Tendon Total Rupture Score (ATRS). The ATRS is a valid questionnaire with high reproducibility and sensitivity for measuring outcome after treatment in patients with total Achilles tendon rupture [14]. The ATRS was originally developed in Swedish, and has been translated and cross-culturally adapted into several languages, including Danish [15], and British English [16, 17]. To facilitate comparison among studies at an international level, cross-cultural adaptation of this questionnaire for the Brazilian population is warranted. The aim of this study was to perform the translation and crosscultural adaptation of the Achilles Tendon Total Rupture Score (ATRS) into Brazilian Portuguese, and to determine its reproducibility and validity. Methods Design This is a cross sectional study approved by the Ethics and Research Committee of our institution (Hospital Mater Dei, Belo Horizonte, Minas Gerais, Brazil). Patients from three tertiary hospitals were included into this study. All were examined for the purposes of the present study in our centre (Orthopedic Department, Hospital Mater Dei, Belo Horizonte, Minas Gerais, Brazil). Page 2 of 6 All patients gave written informed consent to participate in this study. Translation The ATRS is a self-reported questionnaire composed of ten items that reflect the opinion of patients regarding their symptoms, limitations in daily activities and physical activities after a complete rupture of the Achilles tendon. At the end of each question, the patient is given a scale from 0 to 10, where 0 corresponds to more symptoms and greater limitations of physical activity, and 10 indicates no symptoms and limitations. The final score is obtained by the sum of the responses for each item. The ATRS total score ranges from 0 to 100, with higher scores equal to less symptoms and limitations [10] (Additional file 1). The cross-cultural adaptation of the ATRS was divided into 5 phases: initial translation (two bilingual Brazilian translators), synthesis of translation, back-translation (two native English language translators), consensus (...truncated)