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Relative Validity and Reproducibility of a Semi-Quantitative Food Frequency Questionnaire to Assess Nutrient Intakes of Persian Cohort Participants: Comparisons to 24-Hour Dietary Recalls and Selected Biomarkers Publisher Pubmed



Eghtesad S ; Sharafkhah M ; Hekmatdoost A ; Ostadrahimi A ; Farjam M ; Vakilian A ; Pasdar Y ; Kheradmand M ; Shahrakisanavi F ; Mehrparvar AH ; Shayanrad A ; Mohammadi Z ; Seyyedsalehi MS ; Willett WC Show All Authors
Authors
  1. Eghtesad S
  2. Sharafkhah M
  3. Hekmatdoost A
  4. Ostadrahimi A
  5. Farjam M
  6. Vakilian A
  7. Pasdar Y
  8. Kheradmand M
  9. Shahrakisanavi F
  10. Mehrparvar AH
  11. Shayanrad A
  12. Mohammadi Z
  13. Seyyedsalehi MS
  14. Willett WC
  15. Malekzadeh R
  16. Poustchi H

Source: Archives of Iranian Medicine Published:2025


Abstract

BACKGROUND: Food frequency questionnaires (FFQs) are widely used in epidemiologic studies to assess the dietary intake of individuals. In this study, we evaluated the validity and reproducibility of the FFQ used in the Prospective Epidemiological Research Studies in IrAN (PERSIAN) for assessing nutrient intakes. METHODS: Individuals (n=978) from seven PERSIAN cohort centers participated in this study; an initial FFQ was completed for each person upon enrollment (FFQ1), followed by two 24-hour dietary recalls (24HR) each month, for twelve months, and finally, another FFQ at the end of the study (FFQ2). Serum and 24-hour urine (24H-U) samples were also collected each season, and selected biomarkers were measured. To assess validity, correlation coefficients between the 24HRs and the FFQs were obtained. The triad method was used to compare the biomarkers to the FFQs. Correlations between FFQ1 and FFQ2 were evaluated to assess the reproducibility of the questionnaire. RESULTS: Correlations obtained for energy and macronutrients, in comparing FFQ1 and FFQ2 to the 24HRs were 0.57,0.63 (energy), 0.56,0.62 (protein), 0.51,0.55 (lipids) and 0.42,0.51 (carbohydrates), respectively. Moderate (0.4‒0.6) and high (>0.6) correlations were seen for micronutrients, with only vitamins B6 and B12 being poorly correlated (<0.4). Validity coefficients obtained for urinary protein and sodium, as well as serum folate and selected fatty acids were acceptably above 0.4. Reproducibility correlations ranged from 0.18 (alpha-linoleic acid) to 0.78 (selenium), with 19 of the 30 evaluated nutrients showing high and 2 showing poor correlations. CONCLUSION: Overall, the PERSIAN Cohort FFQ is acceptable to rank individuals based on their nutrient intakes. This record is sourced from MEDLINE/PubMed, a database of the U.S. National Library of Medicine