Assessing the reliability and reproducibility of food frequency questionnaire and identify major dietary patterns in overweight and obese adults in Tabriz, Iran

Abstract

Materials and methods: The study included two studies: (1) a pilot study (n = 30) assessment of reliability and reproducibility of FFQ, (2) a cross-sectional study (n = 422) aiming to determine the major dietary pattern of overweight and obese adults. A 189-food item FFQ was completed twice with one-month interval for each subjects. Food consumption over one year for 422 adults aged 20-60 years in Tabriz was collected after assessment of reliability and reproducibility of FFQ. Weight and height were measured and body mass index (BMI) was estimated. Factor analysis was used to determine major dietary pattern.Background and purpose: This study was aimed to assess the reliability and reproducibility of a designed food frequency questionnaire (FFQ) and to determine the major dietary pattern of overweight and obese adults in Tabriz, Iran.Results: Correlation coefficient of the two completed FFQ was varied from 0.60 (for garlic) to 0.97 (for potatoes). Three major dietary patterns were found using factor analysis: "healthy", "western" and "traditional" dietary pattern. Correlation coefficient for the three "Healthy", "Western" and "Traditional" dietary patterns, were 0.90, 0.83 and 0.92, respectively. These dietary patterns included 23% of the total variances.Conclusion: The reliability and reproducibility of the FFQ used in this study was good. There were three major dietary pattern using FFQ among overweight and obese adults in Tabriz. é 2014 Mazandaran University of Medical Sciences. All rights reserved.