The shifting focus from infectious to non-communicable diseases has changed what and how nutritional epidemiology evaluates in the relationships between foods, nutrients and the occurrence of disease. The classically applied vision based on individual nutrients, ‘research from the bottom up’, has now been complemented with new approaches, such as applying the analysis of food combinations (dietary patterns) to study exposure and outcome. Methods of estimating nutrient adequacy have also changed over time, starting from calculating the nutrient adequacy ratio to the use of the probabilistic approach. In the present work constituting Research Activity 1.1, conducted within the EURopean micronutrient RECommendations Aligned Network of Excellence, we have set out to rationalise and harmonise the science of estimating micronutrient intake and nutritional adequacy in Europe. A review of food and nutrition initiatives previously conducted in Europe is presented to set the background and context for the present efforts towards developing a harmonised framework on the dietary assessment of micronutrient intakes.

The objective of the present paper is to review the methods of measuring micronutrient intake adequacy for individuals and for populations in order to ascertain best practice. A systematic review was conducted to locate studies on the methodological aspects of measuring nutrient adequacy. The results showed that for individuals, qualitative methods (to find probability of adequacy) and quantitative methods (to find confidence of adequacy) have been proposed for micronutrients where there is enough data to set an average nutrient requirement (ANR). If micronutrients do not have ANR, an adequate intake (AI) is often defined and can be used to assess adequacy, provided the distribution of daily intake over a number of days is known. The probability of an individual's intake being excessive can also be compared with the upper level of safe intake and the confidence of this estimate determined in a similar way. At the population level, adequacy can be judged from the ANR using the probability approach or its short cut – the estimated average requirement cut-point method. If the micronutrient does not have an ANR, adequacy cannot be determined from the average intake and must be expressed differently. The upper level of safe intake can be used for populations in a similar way to that of individuals. All of the methodological studies reviewed were from the American continent and all used the methodology described in the Institute of Medicine publications. The present methodology should now be adapted for use in Europe.

The purpose of the present study was to conduct a systematic review of the literature on the value of the methods used to assess dietary patterns for measuring nutrient intake adequacy in the population. Systematic review on Pubmed database up to April 2008. The search included specific key words and MeSH terms. No language limit was set. Only studies that compared food patterns with nutrient intake adequacy or nutrient biomarkers were included in the analysis. The search resulted in 1504 articles. The inclusion and exclusion criteria limited the selection to thirty articles. Nineteen studies evaluated the usefulness of the dietary patterns, either a priori defined (thirteen studies), or defined by factor analysis (four studies) or by cluster analysis (two studies), but only nine of them tested their validity (four a priori defined and four a posteriori defined). Diet indices showed moderate to good validity results for measuring the adequacy of intakes for α-carotene, β-carotene, vitamin C, vitamin B6, Ca, folic acid, Fe and Mg. The factor analysis approach showed moderate to good validity correlations with the adequacy of intake of α-carotene, β-carotene, lutein, lycopene, vitamin C, vitamin B6 and folic acid. Vitamin B12 and vitamin E are the micronutrients with less probability of being adequately assessed with dietary patterns a priori or a posteriori defined. Diet indices are tools with fair to moderate validity to assess micronutrient intake adequacy.

Dietary patterns have been related to health outcomes and morbi-mortality. Mediterranean diet indexes are correlated with adequate nutrient intake. The objective of the present study was to analyse the adequacy of nutrient intake of a posteriori defined Mediterranean (MDP) and Western (WDP) diet patterns in the Seguimiento Universidad de Navarra (SUN) cohort. A sample of 17 197 subjects participated in the study. Participants completed a 136-item validated semi-quantitative FFQ. Principal component analysis was used to define dietary patterns. Individuals were classified according to quintiles of adherence based on dietary pattern scores. Non-dietary variables, such as smoking and physical activity habits, were also taken into account. The probability approach was used to assess nutrient intake adequacy of certain vitamins (vitamins B12, B6, B3, B2, B1, A, C, D and E) and minerals (Na, Zn, iodine, Se, folic acid, P, Mg, K, Fe and Ca). Logistic regression analysis was used to assess the adequacy of nutrient intake according to adherence to dietary patterns. WDP and MDP were defined. A higher quintile of adherence to an MDP was associated to a lower prevalence of inadequacy for the intake of Zn, iodine, vitamin E, Mg, Fe, vitamin B1, vitamin A, Se, vitamin C and folic acid. The adjusted OR for not reaching at least six (or at least ten) nutrient recommendations were 0·09 (95 % CI: 0·07, 0·11) (and 0·02 (95 % CI: 0·00, 0·16)) for the upper quintile of MDP and 4·4 (95 % CI: 3·6, 5·5) and 2·5 (95 % CI: 1·1, 5·4) for the WDP. The MDP was associated to a better profile of nutrient intake.

EURopean micronutrient RECommendations Aligned is a network of excellence funded by the European commission, and established to address the problem of differences between countries in micronutrient recommendations as well as to understand how nutritional information including requirements and adequacy of intake is processed among different population groups. The aims of the present paper were to review the methods used for the adequacy assessment of the intake of six micronutrients of public health concern (vitamin A, folate, vitamin B12, Fe, Zn and iodine) in non-European and European nutrition surveys carried out on the apparently healthy population and to compare in particular the adequacy across surveys for folate intake. A systematic literature review was conducted to identify nutrition surveys that assessed micronutrient intake adequacy. The search yielded 9049 records, out of which 337 were eligible for the selected micronutrients. The majority (83·9 %) of the European surveys compared the adequacy of the nutrient intake against the Recommended Dietary Allowances (RDA); only a few surveys (8·0 %) used the estimated average requirement cut-point method, while none of them used the probability approach. The comparison of folate inadequacy across eight countries revealed that about 25 % of the adult female population had inadequate intakes when judged against the different recommendations used by the respective investigators, but nearly 75 % had inadequate intakes when compared against the estimated average requirement cut-point value of 320 μg/d. The present review showed that different methods were applied across Europe to estimate the adequacy of micronutrient intake, which led to different prevalence estimates of micronutrient inadequacy.

The present research was conducted within the framework of the EURopean micronutrient RECommendations Aligned project. In order to identify the best practice in assessing nutrient intakes, a search strategy for collecting data from national food consumption surveys/studies in Europe was developed. Systematic literature searches were carried out on twenty-eight European and the four European Free Trade Association countries. A questionnaire was also sent to two to five experts in each country. Systematic reviews using PubMed yielded 12 703 abstracts that were reduced to 200 studies using inclusion and exclusion criteria. Similarly, a search of ministry web sites yielded 3033 hits, and subsequently reduced to nine surveys. Belgium, France, Germany, Ireland, Sweden, Spain and the United Kingdom were the countries with most data and Slovenia and Liechtenstein were those with the least. Seventy-eight expert questionnaires were obtained from all countries except for Liechtenstein, Luxembourg and Slovakia. Detailed results and references are given. A systematic search and questionnaires are equally good at identifying national surveys across countries. Literature searching provides globally accessible and objective information albeit limited, whereas the questionnaire provides information that, depending upon responders, can be more complete. A combination of both strategies is recommended.

Research was conducted within the EURopean micronutrient RECommendations Aligned (EURRECA) Network of Excellence, to find the best practice in assessing nutrient intakes. Objectives include: to search for and use data on individual nutrient intake adequacy (NIA) assessment collected in twenty-eight European countries and the four European Free Trade Association countries; to design and test innovative tools for data quality analysis. The information was obtained using the method described by Blanquer et al. in the present issue. The best-practice criteria were devised to select the most appropriate survey in each country. Then a survey quality scoring system was developed in consultation with experts and tested on these surveys. Weights were allocated according to a variable priority order agreed by consultation. The thirty-two countries yielded twenty-four national surveys (eight countries excluded). Data collection techniques: eleven countries/surveys used personal interviews only; six used combinations of techniques. Dietary assessment methods: two used repeated 24 h recalls only; eleven used combinations. NIA assessment methods: two used probabilistic approach and sd/Z-scores only; eleven used comparison with estimated average requirements/RDA only. Countries were ranked according to the survey quality scoring, but careful interpretation is needed because of incomplete data from some surveys; bearing this in mind, the information quality is high in 37·5 % countries, medium in 50·0 % and low in 12·5 %. Although there is room for improvement and caution should be taken when drawing conclusions and recommendations from these results, the lessons learned and tools developed at this first attempt form the basis for future work within the EURRECA framework for aligning European micronutrient recommendations.

The present study evaluated how applying different dietary methods affects risk assessment of inadequate intakes at the population level. A pooled analysis was conducted using data from two Spanish regional representative surveys both applying similar methodology with a total sample of 2615 individuals aged 12–80. Diet was assessed in the entire sample applying data from one 24 h recall (24HR), a mean of two non-consecutive 24HR, both crude and adjusted for intraindividual variability, and a FFQ. Intakes of vitamins A, C, E, thiamin, riboflavin, niacin, vitamin B6, vitamin B12, Fe, Mg, P and Zn were compared to the average nutrient requirement (ANR or estimated average requirement) in the entire sample and also excluding under-reporters applying the ANR cut-point method (and the probability approach for Fe). Higher percentages of intakes below the ANR were seen for 1–24HR and the mean of 2–24HR, except for nutrients with the highest rates of inadequacy (vitamins A, E, folate and Mg). For these micronutrients, higher percentages of inadequacy were obtained by adjusted 24HR data and the lowest with FFQ. For the remaining nutrients, adjusted data gave the lowest inadequacy percentages. The best concordance was seen between 2–24HR and 1–24HR as well as for adjusted 24HR, with the least observed between FFQ and the other methods. Exclusion of under-reporters considerably reduced inadequacy in both daily methods and FFQ. Crude daily data gave higher estimates of inadequate intakes than adjusted data or FFQ. Reproducibility of daily methods was also reasonably good. Results may differ depending on the micronutrient thus impeding reaching conclusions/recommendations common for all micronutrients.

In order to assess nutritional adequacy, valid estimates of nutrient intake are required. One of the main errors in dietary assessment is misreporting. The objective was to review the extent, nature and determinants of misreporting in dietary assessment, how this affects reported intakes of micronutrients and how this is identified and measured, and to identify the best ways of dealing with misreporting when interpreting results. A systematic literature search was conducted for studies of misreporting of dietary intake in adults by 24 hour recalls or by estimated or weighed food records, published up to March 2008. Thirty-seven relevant studies were identified. Possible causes of misreporting were identified. Methods most used to identify misreporting were the Goldberg cut-off (46 % studies) and the doubly labelled water technique (24 % studies). The magnitude of misreporting of energy intake was similar in all three dietary assessment methods. The percentage of under-reporters was about 30 % and energy intake was underestimated by approximately 15 %. Seven papers presented usable data for micronutrient intake. Absolute intakes of Fe, Ca and vitamin C (the three micronutrients addressed in all papers) were on average 30 % lower in low-energy reporters (LER) than that in non-LER and, although results were not consistent, there was a tendency for micronutrient density to be higher in LER. Excluding underreporters or using energy adjustment methods for micronutrient intakes is discussed. Residual method of energy adjustment seems to be a good tool for practice to decrease an influence of misreporting when interpreting results of studies based on food records and 24 hour recalls.

Immigrants comprise a noteworthy segment of the European population whose numbers are increasing. Research on the dietary habits of immigrants is critical for correctly providing diet counselling and implementing effective interventions. The aim of the present study was to identify the presently used methods and adaptations required for measuring dietary intake in European immigrant groups. A comprehensive review strategy included a structured MEDLINE search, related references and key expert consultations. The review targeted adults from non-European union (European union-15 countries) ethnic groups having the largest populations in Europe. As studies evaluating nutrient intake were scarce, papers evaluating intake at the level of foods were included. Forty-six papers were selected. Although Eastern Europe, Turkey, Africa (North, Sub-Saharan and Afro-Caribbean), Asia and Latin America represented the most numerous immigrant groups, papers on dietary intake were not available for all populations. Interview-administered FFQ and repeated 24 hour recalls were the most frequently applied instruments. Inclusion of ethnic foods and quantification of specific portion sizes of traditional foods and dishes in assessment tools as well as food composition databases were commonly identified problems. For FFQ, food list elaboration required particular consideration to reflect key ethnic foods and relative contribution to nutrient intake. Extra efforts were observed to overcome cultural barriers to study participation. Evaluating dietary intake of immigrant populations requires special attention to various methodological aspects (sampling, recruiting, instruments used, method of administration, food composition database, acculturation, etc.) so as to adequately address the range of socio-cultural factors inherent in these nutritionally at risk target groups.

In order to assess nutritional adequacy, reliable estimates of nutrient intake are required. Specifically, the EURopean micronutrient RECommendations Aligned (EURRECA) Network of Excellence needs clear guidelines on methods suitable for assessing micronutrient intakes among vulnerable population groups. The objective of this project was to collect, evaluate data and review the suitability of methods used to assess dietary intake of low-income groups across Europe. A comprehensive literature review methodology was employed, which involved structured search MEDLINE, from 1990 to 2008, on (nutrient intake methods) and (validity terms) and (human studies) and finally (low-income terms). In addition, manual searches were conducted for published books and national studies. Seven studies satisfied the selection criteria for inclusion in the review in which four dietary intake methods had been described and validated. Three other studies found in the grey literature used similar methods. Only one study tested a variety of methods to assess reliability and the method preferred by those having low incomes. Preferred methods were 24 h recalls and a FFQ which, compared with the weighed inventory, also yielded higher estimates of energy and nutrient intakes. Many of the methods used in low-income populations have not been subjected to evaluation and consequently may not demonstrate sensitivity and/or specificity when used in this population. Based on one study only, four multiple-pass 24 h recalls are recommended as the most appropriate method for the evaluation of nutritional adequacy in low-income households.

Presently used dietary-assessment methods often present difficulties for researchers and respondents, and misreporting errors are common. Methods using information and communication technologies (ICT) may improve quality and accuracy. The present paper presents a systematic literature review describing studies applying ICT to dietary assessment. Eligible papers published between January 1995 and February 2008 were classified into four assessment categories: computerised assessment; personal digital assistants (PDA); digital photography; smart cards. Computerised assessments comprise frequency questionnaires, 24 h recalls (24HR) and diet history assessments. Self-administered computerised assessments, which can include audio support, may reduce literacy problems, be translated and are useful for younger age groups, but less so for those unfamiliar with computers. Self-administered 24HR utilising computers yielded comparable results as standard methods, but needed supervision if used in children. Computer-assisted interviewer-administered recall results were similar to conventional recalls, and reduced inter-interviewer variability. PDA showed some advantages but did not reduce underreporting. Mobile phone meal photos did not improve PDA accuracy. Digital photography for assessing individual food intake in dining facilities was accurate for adults and children, although validity was slightly higher with direct visual observation. Smart cards in dining facilities were useful for measuring food choice but not total dietary intake. In conclusion, computerised assessments and PDA are promising, and could improve dietary assessment quality in some vulnerable groups and decrease researcher workload. Both still need comprehensive evaluation for micronutrient intake assessment. Further work is necessary for improving ICT tools in established and new methods and for their rigorous evaluation.