Construction and validation of a questionnaire to measure gastrointestinal function in adults

Introduction: Gastrointestinal function can be altered by different clinical circumstances, for example side effects of a treatment. In cancer patients, the gastrointestinal function is modified either due to the location of the tumor in the digestive system or by the side effects of chemotherapy, radiotherapy or surgery. This can be manifested with symptoms that could be a nutritional risk. Aim: To create and validate a questionnaire to measure gastrointestinal function in adults. Material and methods: The construction of the questionnaire was based on different versions. The questionnaire was modified after the opinion and observations of expert panels and a pilot study of 100 patients with cancer. The validation was performed based on the application of the questionnaire to 898 participants. For the statistical analysis Cronbach 's Alpha and Exploratory Factor analysis was performed. Results: The final version of the questionnaire was integrated with 9 items that measure both gastrointestinal symptoms and intestinal rhythm. The KM0 value was 0.850 and Bartlett's Sphericity test was 2914.41 (gl. of 36). The extraction of the factors by Principal Components Analysis distributed the 9 items in 2 dimensions with factors >= 0.40, which represent an accumulated variance of 58.89%. About trustworthy was determined by Cronbach 's Alpha analysis, for the total 9 items the value obtained was 0.844. Conclusions: The design of this questionnaire allows to measure the gastrointestinal function in adults, also the identification of the level of severity of the gastrointestinal symptoms. The confidence levels assure that the questionnaire assess the gastrointestinal function adequately.