Translation, cultural adaptation and validation of a questionnaire about the quality of life of patients with chronic venous ulcers of the lower limbs

Abstract

Chronic ulcers of the lower limbs (CULL) affect up to 5% of adults in Western countries. They are responsible for significant morbidity and mortality, and have a strong economic and social impact, influencing considerably the quality of life (QoL) of patients. Venous ulcer (VU) is responsible for 70% of CULL. Some QoL questionnaires can be applied in patients with VU in order to evaluate this issue. However, because they are generic, these questionnaires can not accurately assess some aspects of QoL of these patients. In this context, Hareendran et al developed a questionnaire (Venous leg ulcer quality of life questionnaire) that proved to be effective in assessing the QoL of patients with chronic VU. Thus, as there is no specific questionnaire for chronic VU being used in a large scale in Brazil, it is necessary to translate and adapt a specific construct in order to use it in clinical practice. OBJECTIVES: To translate the questionnaire The venous leg ulcer quality of life (Vlú-QoL) questionnaire into Portuguese of Brazil, to adapt it to the Brazilian reality, and validate it with patients at the Clinical Hospital (CH) of the Medical School of Botucatu (MSB), UNESP. Secondary Objectives: To evaluate the reproducibility of the questionnaire, adapted to Brazilian Portuguese (VLU-QoL-Br), the impact on the quality of life in subgroups: gender, age, number, size, and duration of ulcers and to evaluate the correlation of VLU-QoL-Br to the measure of willingness to pay by the treatment. METHODOLOGY: The project will be developed in the clinic of chronic ulcers of the institution, involving adult patients of both genders, and people with lower-limb VU, from April to December 2012. The diagnosis of VU (inclusion criteria) will be based on clinical signs and evidence of chronic venous insufficiency. Sampling shall be performed by convenience. The translation of the questionnaire will be held by a professional translator, who does not know the purpose of the topic, and two experts in the area of venous ulcers, fluent in English. The synthesis of the translations will be held in a meeting with the three translators present. It will then be held a pre-interview with ten patients in the CH of the MSB-UNESP, VU carriers, to assess their understanding of the translated questionnaire, and adaptation of the language. The new questionnaire will be applied to 100 patients in the same hospital and reapplied after 7-14 days by the same interviewer, in the same patients, to determine the reproducibility of the construct, provided there is no clinical worsening of the lesions. The questionnaire will be evaluated demographic and clinical information, about the ulcer and the willingness to pay for the treatment. Statistical analysis: The internal consistency of the questionnaire developed will be tested by Cronbach's alpha. The importance of the items will be evaluated from the subtraction of each individual item construct measured in relation to the modification of the Cronbach's alpha. They are considered important items in the questionnaire regarding the continued those that modify the coefficient of fewer than 0.2 units. The total score and each item will be assessed for agreement by intraclass correlation coefficient (absolute agreement). The correlation between the total score (VLU-QoL-Br), area of ulcers, number of ulcers, time of evolution of ulcers, and willingness to pay will be tested by the linear correlation coefficient of Spearman (rs), as well as the correlation between the questionnaire items. Subsequently, the items will be tested in comparison with the original construct by confirmatory factor analysis (path analysis). It will be considered a significant p-value <0.05 two-tailed.(AU)