Search

Objective:Our aim was to evaluate the reproducibility of a food-frequency questionnaire (FFQ) developed in a French population, and its validity against four 24-h dietary recalls (24-HRs).Methods:A total of 57 adults (aged 18–63), 17 adolescents (aged 14–18) and 20 children (aged 10–14) completed four 24-HRs (one per season) and two FFQs over a 1-year interval. Reproducibility of the FFQ was estimated by intraclass correlation coefficients (ICCs). The validity of FFQ was assessed by comparison with the four 24-HRs.Results:For most nutrients, the first FFQ measurements gave higher mean values than the second FFQ. The ICCs for nutrients ranged from 0.39 for total protein to 0.83 for alcohol. The ICCs were higher for food items consumed daily such as milk (0.80) or sugars and confectionery (0.65), and lower for rarely eaten food such as inner organs (0.11). Nutrient intakes as assessed by FFQs were higher than those from the 24-HRs, except for alcohol. The de-attenuated Pearson's correlation coefficient for nutrients varied from 0.25 (dietary fiber) to 0.90 (alcohol), but the adjustment for energy did not improve these coefficients. When nutrient intakes were categorized into quintiles, FFQ and 24-HRs produced agreement rates (same or adjacent quintile) between 55% (for PUFA) and 95% (for alcohol), while misclassification to an extreme quintile was rare (<5%).Conclusion:The FFQ developed for the FLVS II Study can be used to classify adults or adolescents according to their nutrients and food intakes over a 1-year period.European Journal of Clinical Nutrition (2009) 63, 282–291; doi:10.1038/sj.ejcn.1602914; published online 19 September 2007 [ABSTRACT FROM AUTHOR]

Objective:We conducted a dietary validation study in youth aged 1–11 years by comparing dietary intake of omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) as assessed by a parent-completed semiquantitative food frequency questionnaire (FFQ) over time to erythrocyte membrane composition of the same fatty acids.Design:The study population included youth aged 1–11 years who were participants in the Diabetes Autoimmunity Study in the Young (DAISY), a longitudinal study in Denver, Colorado that is following a cohort of youth at risk for developing type I diabetes. Four hundred and four children who had erythrocyte membrane fatty acid data matched to an FFQ corresponding to the same time frame for a total of 917 visits (matches) were included. PUFA intake was expressed both as g/day (adjusted for total energy) and as percent of total fat intake. We used mixed models to test the association and calculate the correlation between the erythrocyte membrane estimates and PUFA intake using all records of data for each youth.Results:Intakes of total omega-3 fatty acids (β=0.52, P<0.0001, ρ=0.23) and marine PUFAs (β=1.62, P<0.0001, ρ=0.42), as a percent of total fat in the diet, were associated with percent of omega-3 and marine PUFAs in the erythrocyte membrane. Intakes of omega-6 PUFAs (β=0.04, P=0.418, ρ=0.05) and arachidonic acid (β=0.31, P=0.774, ρ=0.01) were not associated.Conclusions:In these young children, an FFQ using parental report provided estimates of average long-term intakes of marine PUFAs that correlated well with their erythrocyte cell membrane fatty acid status.European Journal of Clinical Nutrition (2008) 62, 733–738; doi:10.1038/sj.ejcn.1602763; published online 18 April 2007 [ABSTRACT FROM AUTHOR]

Objective: To evaluate validity and reliability of the food-frequency questionnaire (FFQ) developed for the Korean Genome Epidemiologic Study (KoGES). Methods: FFQ was administered twice at 1-year interval (first FFQ (FFQ1) at the beginning and second FFQ (FFQ2) at the end of the study) and diet records (DRs) were collected for 3 days during each of the four seasons from December 2002 to May 2004 for those who attended the health examination center. At the end of the study period, we collected the 12-day DRs of 124 participants. The nutrient intakes from the DRs were compared with both FFQ1 and FFQ2. Results: The intakes of energy and some nutrients estimated from FFQ1 and FFQ2 were different from those assessed by the DRs. Especially, the consumption of carbohydrates was higher in FFQ1 and FFQ2 than in the DRs. The de-attenuated, age, sex and energy intake adjusted correlation coefficients between the FFQ2 and the 12-day DRs in Korean population ranged between 0.23 (Vitamin A) and 0.64 (carbohydrate). The median for all nutrients was 0.39. The correlations were similar when we compared nutrient densities of both methods. Joint classification of calorie-adjusted nutrient intakes assessed by FFQ2 and 12-day DRs by quartile ranged from 25.8% (vitamin A) to 39.5% (carbohydrate, iron) for exact concordance. Except vitamin A, the proportion of subjects classified into distant quartile was less than 7% in all nutrients. The median of correlations between the two FFQs 1 year apart were 0.45 for all nutrient intakes and 0.39 for nutrient densities. Conclusions: We conclude that the FFQ we have developed appears to be an acceptable tool for assessing the nutrient intakes in this population. Further studies for calibration of the FFQ collected from multicenters participating in the KoGES are needed. [ABSTRACT FROM AUTHOR]

Objective:To validate the folate and vitamin B12 intakes estimated by a food-frequency questionnaire (FFQ) designed to be used in a case-control study on the association between maternal dietary intake and the risk of having a child with a congenital heart defect.Design and subjects:The FFQ was filled out by 53 women of reproductive age. Immediately thereafter, blood samples were taken to determine serum folate, red blood cell (RBC) folate and serum vitamin B12 concentrations. Subsequently, three dietary 24-h recalls (24HR) were completed during a period of three successive weeks and used as a reference method. The recalls comprised two weekdays and one weekend day. Using the method of triads, validity coefficients were calculated by comparing nutrient intakes derived from the FFQ and 24HR with the corresponding nutritional biomarkers in blood. The validity coefficient is the correlation between the dietary intake reported by the FFQ and the unknown ‘true’ dietary intake.Results:The comparison of B-vitamin intakes reported by the FFQ and the mean of the 24HR revealed deattenuated correlation coefficients of 0.98 for folate and 0.66 for vitamin B12. The correlation coefficients between the B-vitamin intakes estimated by the FFQ and concentrations of serum folate, RBC folate and serum vitamin B12 were 0.20, 0.28 and 0.21, respectively. The validity coefficients for serum folate, RBC folate and serum vitamin B12 were 0.94, 0.75 and 1.00, respectively. The estimated folate and vitamin B12 intakes were comparable with the results of the most recent Dutch food consumption survey.Conclusions:The adapted FFQ is a reliable tool to estimate the dietary intake of energy, macronutrients, folate and vitamin B12 in women of reproductive age. Therefore, this FFQ is suitable for the investigation of nutrient-disease associations in future.Sponsorship:Funding was provided by the Netherlands Heart Foundation (Grant 2002.B027).European Journal of Clinical Nutrition (2007) 61, 610–615. doi:10.1038/sj.ejcn.1602581; published online 13 December 2006 [ABSTRACT FROM AUTHOR]

BACKGROUND:: Reliability or validity studies are important for the evaluation of measurement error in dietary assessment methods. An approach to validation known as the method of triads uses triangulation techniques to calculate the validity coefficient of a food-frequency questionnaire (FFQ). OBJECTIVE:: To assess the validity of an FFQ estimates of carotenoid and vitamin E intake against serum biomarker measurements and weighed food records (WFRs), by applying the method of triads. DESIGN:: The study population was a sub-sample of adult participants in a randomised controlled trial ofß-carotene and sunscreen in the prevention of skin cancer. Dietary intake was assessed by a self-administered FFQ and a WFR. Nonfasting blood samples were collected and plasma analysed for five carotenoids (a-carotene,ß-carotene,ß-cryptoxanthin, lutein, lycopene) and vitamin E. Correlation coefficients were calculated between each of the dietary methods and the validity coefficient was calculated using the method of triads. The 95%confidence intervals for the validity coefficients were estimated using bootstrap sampling. RESULTS:: The validity coefficients of the FFQ were highest fora-carotene (0.85) and lycopene (0.62), followed byß-carotene (0.55) and total carotenoids (0.55), while the lowest validity coefficient was for lutein (0.19). The method of triads could not be used forß-cryptoxanthin and vitamin E, as one of the three underlying correlations was negative. CONCLUSIONS:: Results were similar to other studies of validity using biomarkers and the method of triads. For many dietary factors, the upper limit of the validity coefficients was less than 0.5 and therefore only strong relationships between dietary exposure and disease will be detected. SPONSORSHIP:: National Health and Medical Research Council.European Journal of Clinical Nutrition (2005) 59, 211-218. doi:10.1038/sj.ejcn.1602060 Published online 13 October 2004 [ABSTRACT FROM AUTHOR]

OBJECTIVE:: Nutritional status and lifestyle can have profound effects on health. To analyse behaviour patterns in population subgroups of public health importance, we compared lifestyle, dietary intake of energy and selected nutrients, and nutritional biomarkers of type 1 diabetes (T1DM) patients and nondiabetic first-degree relatives against control subjects with no family history of T1DM. DESIGN:: A cross-sectional study. SETTING:: Department of Internal Medicine, University of Pisa, Italy. SUBJECTS:: A total of 209 individuals including 38 type 1 patients, 76 relatives, and 95 healthy subjects. INTERVENTIONS:: We used the European Prospective Investigation of Cancer and Nutrition questionnaires to assess dietary intake and lifestyle. Anthropometric indices and nutritional biomarkers (such as plasma levels of albumin, iron, lipids, homocysteine, vitamin B9 and vitamin B12 as well as urinary outputs of nitrogen, sodium and potassium) were evaluated. RESULTS:: Emerging health issues:(1) In total, 45%of controls were overweight. Increasing age was associated with increasing body mass and decreasing activity in sport in front of an unchanged energy intake.(2) The distribution of energy sources was incorrect. The proportion of caloric intake derived from total fat and cholesterol did not match general guidelines. Total dietary fibre consumption was assessed to be adequate (25?g/day) in only 27%of all the participants.(3) Estimated daily intakes of water-soluble vitamin B9 and fat-soluble vitamin D and vitamin E were deficient in comparison with dietary reference intakes.(4) The prevalence of adoption and maintenance of healthful eating and physical activity habits was higher in women and T1DM patients (probably as a consequence of the medical educational intervention). On the contrary, supportiveness of the family in term of changing the undesirable behaviours at home seemed to fail. CONCLUSIONS:: This study provides first evidence indicating unhealthy dietary behaviours, which could even predispose to the development of diabetes and cardiovascular complications, in subjects living in Pisa. The combination of vitamin B9 and vitamin E deprivation could be deleterious for endothelial function, since these antioxidants have been implicated in the modulation of nitric oxide and eicosanoid signalling. SPONSORSHIP:: This study was supported by a grant from the Ministry of Education, University and Research, Italy.European Journal of Clinical Nutrition (2005) 59, 114-122. doi:10.1038/sj.ejcn.1602047 Published online 1 September 2004 [ABSTRACT FROM AUTHOR]