Development of the Portuguese Version of the Celiac Disease Questionnaire

Abstract

Celiac disease is characterized as a permanent and chronic intolerance to the gluten ingestion. The only effective treatment is the lifelong gluten-free diet, which implies radical changes in the patient’s life and eating habits with a constant challenge and potential shifts in their health-related quality of life. The health-related quality of life occupies an important place as a research subject in different areas of human activity. However we do not found in the literature specific instruments adapted to the Portuguese reality that could measure the health-related quality of life in celiac patients. Then our goal is to develop the Portuguese version of the Celiac Disease Questionnaire - CDQ (developed by Dr. Winfried Häuser team in 2007), which may contribute to the identification of factors that influence the adult celiac patients health-related quality of life. We carried out the translation, cultural and functional equivalence of measures with a preliminary study. Subsequently we applied the CDQ to 231 celiac patients and proceeded with a component analysis and reliability. As in the original version, the analysis of the Portuguese version suggests the existence of a four dimensions model with a KMO coefficient of 0.897. Nevertheless, we obtained a different item factor loading in each dimension: emotional experience, social participation, fears and concerns, gastrointestinal symptoms. For each dimension the Cronbach's α ranged from 0.71 to 0.89 and an overall value of 0.91. The Portuguese version of the CDC proved to be a specific instrument for health-related quality of life assessment in adult celiac patients.