This study was conducted to validate a food frequency questionnaire (FFQ) to assess vitamin K intake in clinical and research settings based on data from the Fifth Korea National Health and Nutrition Examination Survey (KNHANES V). We collected a subset of data on informative food items using the 24-hour recall method from adults aged 19 to 64 years from KNHANES V. The cumulative percent contribution and cumulative multiple regression coefficients for vitamin K intake from each food were computed. Twenty-five foods items were selected for the FFQ to assess vitamin K intake. The FFQ was validated against intakes derived from a 5-day food record (5DR) (n = 48). To assess the reliability of the FFQ, participants completed the self-administered FFQ (FFQ1) and a second FFQ (FFQ2) after a 6-month period (n = 54). Data were analyzed using Pearson's correlation coefficients, the cross-classification method, and Bland-Altman plots. Mean intakes were similar for vitamin K between the FFQ and dietary records, with significant correlations observed (r = 0.652), and cross-classification analyses demonstrated no major misclassification of participants into intake quartiles. Bland-Altman plots showed no serious systematic bias between the administrations of the two dietary assessment methods over the range of mean intakes. FFQ reliability was high, with a Pearson's correlation coefficient of 0.560. This pilot study shows promising validation and reliability evidence for the use of this FFQ, which is focused on vitamin K intake in adults, as an efficient screening tool in clinical and research settings.
Citations
As prevalence of metabolic syndrome has rapidly increased over the past decade, lifestyle changes including dietary habits are considered as a therapeutic cornerstone for metabolic syndrome, cardiovascular complications and type 2 diabetes. We evaluated the effectiveness of a telephone-delivered nutrition education to improve metabolic parameters compared with a single-visit with a dietitian in subjects with metabolic syndrome. A total of seventy-one adults who met diagnostic criteria for the metabolic syndrome were randomly assigned to either the single-visit group or the in-depth nutrition education group during a 3-month intervention study period. The in-depth telephone-delivered nutrition education group had an initial visit with a dietitian and additional two telephone counseling during the first 4 weeks of the study periods. Sixty-six subjects completed a 3-month intervention study. The trial examined participant's anthropometric changes and dietary intakes as well as changes in the metabolic syndrome factors. At the end of the trial, the in-depth nutrition education group showed significantly higher reduction in weight, body fat and abdominal circumference compared with the other group (p < 0.05). In the in-depth nutrition groups, the prevalence of metabolic syndrome was decreased to 45.5%, while 69.7% of the subjects were metabolic syndrome patients in the single-visit group (p < 0.05). These results demonstrate that the telephone-intervention counseling is a feasible mean to deliver dietary intervention in patients with metabolic syndrome.
Citations
First
Prev
