Validity and reproducibility of a FFQ for assessing dietary intake among residents of northeast China: northeast cohort study of China

Abstract

Purpose: To evaluate the reproducibility and validity of the food frequency questionnaire (FFQ) for residents of northeast China. Methods: A total of 131 participants completed two FFQs (FFQ1 and FFQ2) within a 3-month period, 125 participants completed 8-day weighed diet records (WDRs), and 112 participants completed blood biomarker testing. Reproducibility was measured by comparing nutrient and food intake between FFQ1 and FFQ2. The validity of the FFQ was assessed by WDRs and the triad method. Results: The Spearman correlation coefficients and intraclass correlation coefficients (ICCs) for reproducibility ranged from 0.41 to 0.69 (median = 0.53) and from 0.18 to 0.68 (median = 0.53) for energy and nutrients and from 0.37 to 0.73 (median = 0.59) and from 0.33 to 0.86 (median = 0.60) for food groups, respectively. The classifications of same or adjacent quartiles ranged from 73.64% to 93.80% for both FFQs. The crude Spearman correlation coefficients between the FFQ and WDRs ranged from 0.27 to 0.55 (median = 0.46) for the energy and nutrients and from 0.26 to 0.70 (median = 0.52) for food groups, and classifications of the same or adjacent quartiles ranged from 65.32% to 86.29%. The triad method indicated that validation coefficients for the FFQ were above 0.3 for most nutrients, which indicated a moderate or high level of validity. Conclusions: The FFQ that was developed for residents of northeast China for the Northeast Cohort Study of China is reliable and valid for assessing the intake of most foods and nutrients.

Intake of ultra-processed foods and asthenozoospermia odds: A hospital-based case-control study

“…The FFQ used in the present study was based on FFQ used in a large cohort study in the northeast of China ( 29 , 30 ). The reproducibility and validity of the FFQ used in the current study were similar to FFQ used in previously published literature ( 11 , 30 – 32 ). The FFQ included seven frequency categories (“never,” “two to three times per month,” “one time per week,” “two to three times per week,” “four to six times per week,” “one time per day,” and “more than two times per day”) for each food item.…”

Nutrients-Rich Food Index Scores and the Overall Survival of Ovarian Cancer Patients: Results from the Ovarian Cancer Follow-Up Study, a Prospective Cohort Study

“…The dietary intakes of OC patients were collected at recruitment through a validated 111-item food frequency questionnaire (FFQ) with reasonable reliability and validity. For most food items, the reproducibility coefficients (intraclass and spearman) were above 0.5, and the spearman correlation coefficients were 0.3–0.7 between the FFQ and weighed dietary records [ 21 ]. All participants were needed to check the usual frequency consumption for each food item with standard serving sizes over 12 months before the diagnosis of OC through the FFQ, which was carried out by skilled and well-trained personnel via face-to-face interviews.…”

Purine Intake and All-Cause Mortality in Ovarian Cancer: Results from a Prospective Cohort Study

“…A validated 111-item food-frequency questionnaire (FFQ) was used to collect dietary data, which was validated previously [ 24 ]. The reproducibility coefficients (intraclass correlation coefficients and Spearman correlation coefficients) for the majority of food groups were over 0.5, whereas correlation values (Spearman correlation coefficients) between the FFQ and weighted diet records for the majority of food groups ranged from 0.3 to 0.7 [ 13 , 22 ].…”