Reproducibility and validity of an FFQ developed for adults in Nanjing, China

摘要

We evaluated the reproducibility and validity of an FFQ used in a Chinese community-based nutrition and health survey. A total of ninety-nine males and 104 females aged 31-80 years completed four three consecutive 24-h dietary recalls (24-HDR, served as a reference method, one three consecutive 24-HDR for each season) and two FFQ (FFQ1 and FFQ2) over a 1-year interval. The reproducibility of the FFQ was estimated with correlation coefficients, misclassification and weighted. statistic. The validity was evaluated by comparing the data obtained from FFQ2 with the mean 24-HDR (m24-HDR). Compared with the m24-HDR, the FFQ tended to underestimate intake of most nutrients and food groups. For all nutrients and food groups, the Spearman's and intra-class correlation coefficients between FFQ1 and FFQ2 ranged from 0.66 to 0.88 and from 0.65 to 0.87, respectively. Most correlation coefficients decreased after adjusting for energy. More than 90% of the subjects were classified into the same or adjacent categories by both FFQ. For all nutrients and food groups, the crude, energy-adjusted and de-attenuated Spearman's correlation coefficients between FFQ2 and the m24-HDR ranged from 0.21 to 0.69, 0.19 to 0.58 and 0.25 to 0.71, respectively. More than 70% of the subjects were classified into the same and adjacent categories by both instruments. Both weighted. statistic and the Bland-Altman plots showed reasonably acceptable agreement between the FFQ2 and the m24-HDR. The FFQ developed for adults in the Nanjing area can be used to reliably and validly measure usual intake of major nutrients and food groups.