Translation and cross-cultural adaptation of the Persian version of inflammatory bowel disease-fatigue (IBD-F) self-assessment questionnaire

This data was used to evaluate the cross-cultural adaptation (validity and reliability) of the Persian version of inflammatory bowel disease-fatigue (IBD-F) self-assessment questionnaire. The original IBD-F questionnaire was translated into the Persian version in a standard forward-back manner. Construct validity was checked through the face and content validity (ratio (CVR) and index(CVI)). Fifteen experts were asked to score each item's necessity on an ordinal Likert scale of three; then, the content validity ratio was calculated using the Lawshe formula. Eight judges from a previously defined panel were asked to donate a score on an ordinal Likert scale of four to each item concerning its relevancy, clarity, and simplicity to compute the individual-CVI. Average individual-CVIs were considered as the Scale-CVI for each domain. Twenty lay experts (chosen from the target population) were asked to declare their opinion about each item's importance by donating a 5-point Likert scale; subsequently, face validity was determined by the impact score formula. Questions meeting the minimum values of CVR, CVI, and impact score were retained in the final version of the questionnaire for reliability appraising. Internal consistency and test-retest reliability were checked using Cronbach's α and intraclass correlation coefficients (ICC). Fifty-four patients were recruited based on inclusion and exclusion criteria to participate in the reliability analysis. Internal consistency and test-retest reliability were checked using Cronbach's α and intraclass correlation coefficients (ICC).