| Median (IqR) | | | Cross-classification into quartiles; n (%) | |
---|
FFQ1 | FFQ2 | ICC | Cronbach’s alpha | Correctly classifieda | Grossly misclassifiedb | Cohen’s Kappa |
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Whole grain (g) | 16.2 (15.6) | 20.8 (16.6) | 0.989 | 0.995 | 50 (100) | 0 | 0.653*** |
- aClassified into the same or adjacent (±1) quartile;
- bClassified into opposing quartiles (by ≥2 quartiles)
- ***p < 0.001
- IqR interquartile range, FFQ1 first administration of the food frequency questionnaire, FFQ2 second administration of the food frequency questionnaire, ICC intra-class correlation coefficient