Quality of life in coeliac patients: Italian validation of a coeliac questionnaire

BACKGROUND: Coeliac disease (CD) is a chronic condition requiring a gluten-free diet, which is a very demanding diet to maintain on a life-long basis. For this reason it is a condition that can have serious repercussions on the quality of life (QOL). Therefore the need to elaborate a questionnaire on QOL specifically for patients with CD (CDQ): its original language is German, and the translation/validation process represents a considerable challenge involving not only a translation into Italian but also an adaptation to the country's specific cultural differences. METHODS: The questionnaire has been translated according to a "German → Italian → Italian → German" algorithm with reconciliation of the differences. Scores for CDQ are computed overall and over four areas of four items each: emotion, gastrointestinal symptoms, gastrointestinal worries, social problems. RESULTS: CDQ was administered to 171 coeliacs (F 132, mean age 38 yrs ± 14). Completeness was optimal. Item internal consistency was satisfied for 100% and 97% of patients for the specific and generic part, respectively. Cronbach's α coefficient was 0.7 for all scales. The general CDQ was higher in patients reporting subjective well-being (discriminant validity). CONCLUSIONS: The Italian translation of CDQ sounds natural, is easy to understand and reduces possible cultural biases to a minimum. A field test gave results comparable to the original validation, supporting the use of CDQ in cross-national surveys.