Validity and reproducibility of a semi-quantitative multiple-choice food frequency questionnaire in adults living in central Iran

Abstract

Background: To the best of our knowledge, no study has tried to develop and validate a multiple-choice food-based FFQ in Iran using weighed dietary records.This study aimed to investigate the validity and reproducibility of a multiple-choice semi-quantitative food frequency questionnaire (SQ-FFQ) in adults living in central Iran.Methods: Participants attended a large long-term clinical trial were asked to complete three SQ-FFQs by interview, and nine 3-day weighed dietary records (WDRs), over nine months. They provided two blood samples to assess serum calcium, magnesium, zinc, and vitamin C levels. The Pearson and intraclass correlation coefficients (ICC) were calculated to assess reproducibility and validity. The degree of misclassification was explored by using a contingency table of quartiles which is compare the information between third FFQ and WDRs. The method of triads was incorporated to assess validity coefficients between estimated intakes using third FFQ, WDRs, and biochemical markers and assumed true intakes.Results: A total of 180 adults aged 48.9±8.4 years completed the study. Compared to WDRs, FFQs overestimated all nutrients intakes except for iron. The median Pearson correlation coefficient was 0.31, 0.44, and 0.38 for FFQ1-FFQ2, FFQ1-FFQ3 and FFQ2-FFQ3, respectively and ICC ranged from 0.43 (thiamin) to 0.73 (vitamin D, median: 0.56). The de-attenuated, age, sex, and education adjusted correlation coefficients ranged from 0.01 for vitamin A to 0.40 for vitamin B12 and -0.05 for vitamin A to 0.41 for manganese (median: 0.17 and 0.26) for FFQ1-WDR and FFQ3-WDR, respectively. The median exact agreement and complete disagreement between FFQ3 and WDRs were 33% and 6%, respectively. The FFQ3 validity coefficients for vitamin C, calcium, magnesium, and zinc were 0.13, 0.62, 0.89, and 0.66, respectively, using the triads method.Conclusions: The SQ-FFQ seems to be an acceptable tool to assess the long-term dietary intake for future large-scale studies in this population.

The association between dietary approaches to stop hypertension diet and mediterranean diet with metabolic syndrome in a large sample of Iranian adults: YaHS and TAMYZ Studies

“…The participants were provided with exact explanations about the portion sizes using household scales by the interviewer. In the next stage, single food items were combined into 40 groups based on their similarity and consumption rate (grams per day) and finally the nutrient intakes were computed (Mirmiran et al, 2010;Mirzaei et al, 2017;Salehi-Abargouei et al, 2020).…”

“…The participants' dietary intakes were examined using the validated food frequency questionnaire (FFQ) containing 178 food items and 551 questions. The validity and reliability of this FFQ has been assessed in Iran (Mirmiran et al, 2010;Salehi-Abargouei et al, 2020). Participants were asked to report their usual consumption frequency of food items in the last 12 months.…”

Dietary patterns in association with sleep duration in Iranian Adults: Results from YaHS-TAMYZ and shahadieh cohort studies

“…The detailed information of dietary intakes of adults who participated in the YaHS study was separately collected in the Yazd nutrition survey [called Taghzieh Mardom Yazd (TAMYZ) in Persian] using a semi-quantitative food frequency questionnaire (FFQ) which its validity and reproducibility have been previously reported. [ 24 ] The methodology of the YaHS-TAMYZ study has been published in detail elsewhere. [ 25 ] The Shahedieh study is a subset of the nationwide population-based cohort study (Persian cohort) that including 180,000 persons from 18 geographically distinct areas of Iran,[ 26 ] and Shahedieh is one part of those areas in which 9977 adults were included.…”

The Association Between Major Dietary Patterns and Severe Mental Disorders Among a Large Sample of Adults Living in Central Iran: Baseline Data of YaHS-TAMYZ Cohort Study

“…The dietary assessment in TAMYZ was done by using a 178-item semi-quantitative multiple-choice FFQ which showed an acceptable validity and reliability [27]. For each food item, participants were asked to report the i) frequency of food consumption in the past year based on 10 multiple-choice frequency response categories varying from 'never or less than once a month' to '10 or more times per day', and ii) amount of food consumed each time (portion size).…”