| Objective: To estimate validity of Block food frequency questionnaire (FFQ), Dietary History Questionnaire (DHQ) and Diet records in IBD patients.;Methods: Nutrient intake data from 54 subjects participating in a 12-month, randomized, placebo controlled, dietary intervention study in Crohn's disease (CD), were analyzed to evaluate the validity and agreement between the three instruments ( the Block food frequency questionnaire (Block-FFQ), the Dietary History Questionnaire (DHQ), and 14 day diet diaries (DD)) used to measure dietary intake.;Results: There was good agreement between the two FFQs for all of the nutrients. The estimated correlations between the DDs and two questionnaires for the log transformed nutrients ranged from -0.04 for polyunsaturated fat to 0.77 for calcium and cholesterol. Niacin, monounsaturated fat and polyunsaturated fat are the three nutrients that showed poor agreement between the dietary assessment measures.;Conclusion: FFQs give similar information to DDs in patients with CD. DDs seem to be more captive when there is excess intake of one or more unusual food items or avoidance of certain foods in CD patients who may be eating an altered diet due to symptoms or due to the mere fact that they have a gastrointestinal illness. However, FFQs turn out to be more informative in cases where the DDs are sparsely filled. Dietary intervention studies in patients with Crohn's disease should consider using DD and one of the FFQs to obtain complementary information from both sources. |
