Development and validation of a questionnaire investigating endurance athletes practices to manage gastrointestinal symptoms around exercise

Aim: To develop and validate a questionnaire investigating endurance athletes' carbohydrate beliefs, knowledge, information sources, and other dietary and non-dietary practices related to exercise-associated gastrointestinal symptoms. Methods: A questionnaire was developed by a review of relevant literature and sports-related questionnaires, and input from five experienced sports dietitians. Item construct and format was adapted and modified from a previous questionnaire. The modified questionnaire sought information on demographics, nutrition knowledge, beliefs, intended practices, information sources and exercise-associated gastrointestinal symptoms. A five-phase validity process was conducted to determine content, face and construct validity, item difficulty and internal reliability of the questionnaire. The Delphi technique was applied with experts over three anonymous rounds. Items were reviewed to determine whether to keep, modify, or delete, rate the relevance of each item using a content validity index (CVI), and provide comments. A content analysis was conducted on all comments after each round. Online interviews were conducted with a pilot group of endurance athletes (n = 15) to assess item difficulty and feasibility. Nutrition knowledge was compared between pilot group of athletes and experts to determine construct validity and internal consistency. A test-retest process was applied to a second pilot group (n = 8) to verify questionnaire reliability. Results: High CVI (>=.83) and agreement scores were obtained through the Delphi technique. High reliability (r = .942) and acceptable internal consistency (alpha = .53-.78) of the questionnaire were obtained. Conclusions: The questionnaire was shown to be a valid and reliable tool that will be of use for clinicians and research purposes.