Dietary assessment methods for micronutrient intake in pregnant women : a systematic review

The EURopean micronutrient RECommendations Aligned (EURRECA) Network of Excellence needs clear guidelines for assessing the validity of reported micronutrient intakes among vulnerable population groups. A systematic literature search identified studies validating the methodology used for measuring usual dietary intake during pregnancy. The quality of each validation study selected was assessed using a EURRECA-developed scoring system. The validation studies were categorised according to whether the study used a reference method that reflected short-term intake (,7 d) long-term intake ($7 d) or used biomarkers (BM). A correlation coefficient for each micronutrient was calculated from the mean of the correlation coefficients from each study weighted by the quality of the study. Seventeen papers were selected, which included the validation of fifteen FFQ, two dietary records (DR), one diet history and a Fe intake checklist. Estimates of twenty-six micronutrients by six FFQ were validated against 24-h recalls indicating good correlation for six micronutrients. Estimates of twenty-four micronutrients by two FFQ were validated against estimated DR and all had good or acceptable correlations. Estimates of fourteen micronutrients by three FFQ were validated against weighed DR indicating good correlations for five. Six FFQ were validated against BM, presenting good correlations only for folic acid. FFQ appear to be most reliable for measuring short-term intakes of vitamins E and B6 and long-term intakes of thiamin. Apart from folic acid, BM do not add any more certainty in terms of intake method reliability. When frequency methods are used, the inclusion of dietary supplements improves their reliability for most micronutrients

Genetic differentiation of three species of Matthiola (Brassicaceae) in the Sicilian insular system

We examined the genetic variation of 12 isozyme loci in 14 populations of Matthiola (Brassicaceae) representing the geographic distribution of the species M. incana, M. fruticulosa ssp.fruticulosa and M. tricu.spidata in the Sicilian insular system and the adjacent mainland areas to estimate the levels and apportionment of genetic variation in the insular populations and to understand their population dynamics. The disparity in the distribution of polymorphism in populations of M. incana ssp. incana (low within populations but with high values of FST and GST) contrasts with the homogeneity in the inter-population distribution of the high genetic variation detected in M . tricuspidata and M. fruticulosa ssp. fruticulosa . While the low polymorphism found in M. incana ssp. incana is consistent with its origin through cultivation and the associated lack of gene flow, the Sicilian populations of the other two taxa probably derived from multiple founder events from nearby continental areas and,according to our estimates, have maintained high interpopulational gene flow. Unlike M . incana, the Sicilian populations of M. tricuspidata and M .fruticulosa ssp. Futiculosa could have survived thebglaciations in refugia. This higher antiquity, togetherbwith the maintenance of abundant gene flow, largely explains their high values of genetic variation. In contrast, M. incana ssp. pulchella and M. incana ssp. rupestris have low indices of polymorphism and they are probably neo-endemics, as their distribution areas were severely affected by the Plio-Pleistocene glaciations

Evaluating the quality of dietary intake validation studies

Within the EURopean micronutrient RECommendations Aligned Network of Excellence (EURRECA), a scoring system was developed to assess the quality of dietary intake validation studies. The scoring system included three steps. The first step was to give each study a quality score, which included five components: sample size, statistics used, data collection procedure, consideration of seasonality and supplement use. Scores ranged front 0 to 7, and validation studies classified as very good (>= 5), good (5-3.5), acceptable/reasonable (3.5-2.5) and poor (<2.5). The second and third steps included ail adjustment/weighting of the correlation coefficient according to the quality score and moreover a rating of the adjusted/weighted correlation. The scoring system was tested in 124 validation studies that included at least one vitamin. Only 5.6% of the 124 studies were judged to be of very good quality according to the quality score, 41.9% of good quality and 16.9% had a poor rating. When adjusting for the study quality scores, crude and adjusted mean correlations of vitamins A, C, D and E intakes were similar, but the percentage of correlation values classified as poor or very good was higher after adjustment. These results show the importance of considering the quality Of Studies validating dietary assessment methods and the correlations obtained for the micronutrient of interest when interpreting effects observed in epidemiological studies using dietary assessment methods. Without a doubt, this subject Constitutes a key topic for research in nutritional epidemiology

Observations of Comets

International audienc

Observations of Comets

International audienc

Observations of Comets

International audienc