The European Prospective Investigation into Cancer and Nutrition (EPIC) is an ongoing multi-centre prospective cohort study designed to investigate the relationship between nutrition and cancer, with the potential for studying other diseases as well. The study currently includes 519 978 participants (366 521 women and 153 457 men, mostly aged 35-70 years) in 23 centres located in 10 European countries, to be followed for cancer incidence and cause-specific mortality for several decades. At enrolment, which took place between 1992 and 2000 at each of the different centres, information was collected through a non-dietary questionnaire on lifestyle variables and through a dietary questionnaire addressing usual diet. Anthropometric measurements were performed and blood samples taken, from which plasma, serum, red cells and buffy coat fractions were separated and aliquoted for long-term storage, mostly in liquid nitrogen. To calibrate dietary measurements, a standardised, computer-assisted 24-hour dietary recall was implemented at each centre on stratified random samples of the participants, for a total of 36 900 subjects. EPIC represents the largest single resource available today world-wide for prospective investigations on the aetiology of cancers (and other diseases) that can integrate questionnaire data on lifestyle and diet, biomarkers of diet and of endogenous metabolism (e.g. hormones and growth factors) and genetic polymorphisms. First results of case-control studies nested within the cohort are expected early in 2003. The present paper provides a description of the EPIC study, with the aim of simplifying reference to it in future papers reporting substantive or methodological studies carried out in the EPIC cohort.

The European Prospective Investigation into Cancer and Nutrition (EPIC), which covers a large cohort of half a million men and women from 23 European centres in 10 Western European countries, was designed to study the relationship between diet and the risk of chronic diseases, particularly cancer. Information on usual individual dietary intake was assessed using different validated dietary assessment methods across participating countries. In order to adjust for possible systematic over-or underestimation in dietary intake measurements and correct for attenuation bias in relative risk estimates, a calibration approach was developed. This approach involved an additional dietary assessment common across study populations to re-express individual dietary intakes according to the same reference scale. A single 24-hour diet recall was therefore collected, as the EPIC reference calibration method, from a stratified random sample of 36 900 subjects from the entire EPIC cohort, using a software program (EPIC-SOFT) specifically designed to standardise the dietary measurements across study populations. This paper describes the design and populations of the calibration sub-studies set up in the EPIC centres. In addition, to assess whether the calibration sub-samples were representative of the entire group of EPIC cohorts, a series of subjects' characteristics known possibly to influence dietary intakes was compared in both population groups. This was the first time that calibration sub-studies had been set up in a large multi-centre European study. These studies showed that, despite certain inherent methodological and logistic constraints, a study design such as this one works relatively well in practice. The average response in the calibration study was 78.3% and ranged from 46.5% to 92.5%. The calibration population differed slightly from the overall cohort but the differences were small for most characteristics and centres. The overall results suggest that, after adjustment for age, dietary intakes estimated from calibration samples can reasonably be interpreted as representative of the main cohorts in most of the EPIC centres.

Guarantor: N Slimani. Contributors: NS was the overall coordinator of the ENDB project and in charge of the preparation of the paper in collaboration with the other co-authors. GD, JV, GS, SS, MP, IU, DATS, NS were members of the 'task force group' involving specific managerial or technical tasks for the project and/or the preparation of reference ENDB guidelines. IU was also in charge of the development of the DBMS in collaboration with the coordinating centre. SS, MP, PG, AM, JI, WB, AF, SW, EV, JU, SC and AB were involved as the national compilers in charge of documenting, compiling and evaluating the subset of their national nutrient databases used in the ENDB project. AM, JI, WB and IU were also involved as members of the 'ENDB expert group' headed by DATS, in charge of revising the reference ENDB guidelines. MN, MCB-R, CS, AT, SN, IM, JR, HB, MO, PHMP, PJ, PA, DE, EL, MS de M, AT, KG, CS, SR, AW, SB were involved as local EPIC collaborators in the supervision and preparation of EPIC-specific databases relevant to the ENDB project (e.g. recipe files). CC and MvB, at the coordinating centre, were involved in tasks relevant to these EPIC databases. AFS has provided long-standing scientific collaboration and support for setting up the ENDB. ER is the overall coordinator of the EPIC study. All co-authors provided comments and suggestions on the manuscript. Objective: This paper describes the ad hoc methodological concepts and procedures developed to improve the comparability of Nutrient databases (NDBs) across the 10 European countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). This was required because there is currently no European reference NDB available. Design: A large network involving national compilers, nutritionists and experts on food chemistry and computer science was set up for the 'EPIC Nutrient DataBase' (ENDB) project. A total of 550-1500 foods derived from about 37 000 standardized EPIC 24-h dietary recalls (24-HDRS) were matched as closely as possible to foods available in the 10 national NDBs. The resulting national data sets (NDS) were then successively documented, standardized and evaluated according to common guidelines and using a DataBase Management System specifically designed for this project. The nutrient values of foods unavailable or not readily available in NDSs were approximated by recipe calculation, weighted averaging or adjustment for weight changes and vitamin/mineral losses, using common algorithms. Results: The final ENDB contains about 550-1500 foods depending on the country and 26 common components. Each component value was documented and standardized for unit, mode of expression, definition and chemical method of analysis, as far as possible. Furthermore, the overall completeness of NDSs was improved (X99%), particularly for b-carotene and vitamin E. Conclusion: The ENDB constitutes a first real attempt to improve the comparability of NDBs across European countries. This methodological work will provide a useful tool for nutri...

It is considered that fruit and vegetable (F&V) protect against oesophagus and gastric cancer (GC). However, 2 recent meta‐analyses suggest that the strength of association on GC seems to be weaker for vegetables than for fruit and weaker in cohort than in case‐control studies. No evidence exists from cohort studies about adenocarcinoma of oesophagus (ACO). In 521,457 men and women participating in the EPIC cohort in 10 European countries, information of diet and lifestyle was collected at baseline. After an average of 6.5 years of follow‐up, a total of 330 GC and 65 ACO, confirmed and classified by a panel of pathologists, was used for the analysis. We examined the relation between F&V intake and GC and ACO. A calibration study in a sub‐sample was used to control diet measurement errors. In a sub‐sample of cases and a random sample of controls, antibodies against Helicobacter pylori (Hp) were measured and interactions with F&V were examined in a nested case‐control study. We observed no association with total vegetable intake or specific groups of vegetables and GC risk, except for the intestinal type, where a negative association is possible regarding total vegetable (calibrated HR 0.66; 95% CI 0.35–1.22 per 100 g increase) and onion and garlic intake (calibrated HR 0.70; 95% CI 0.38–1.29 per 10 g increase). No evidence of association between fresh fruit intake and GC risk was observed. We found a negative but non significant association between citrus fruit intake and the cardia site (calibrated HR 0.77; 95% CI 0.47–1.22 per 100 g increase) while no association was observed with the non‐cardia site. Regarding ACO, we found a non significant negative association for vegetable intake and for citrus intake (calibrated HRs 0.72; 95% CI 0.32–1.64 and 0.77; 95% CI 0.46–1.28 per 100 and 50 g increase, respectively). It seems that Hp infection does not modify the effect of F&V intake. Our study supports a possible protective role of vegetable intake in the intestinal type of GC and the ACO. Citrus fruit consumption may have a role in the protection against cardia GC and ACO. © 2005 Wiley‐Liss, Inc.

Background: Dietary supplement use is increasing, but there are few comparable data on supplement intakes and how they affect the nutrition and health of European consumers. The aim of this study was to describe the use of dietary Correspondence: G Skeie, Institute of Community Medicine, University of Tromsø, N-9037 Tromsø, Norway. E-mail: Guri.Skeie@uit.no Guarantor: G Skeie Contributors: GS performed statistical analyses and wrote the article. NS was the overall coordinator of this project and of the EPIC nutritional databases (ENDB) project. GS, ML, PA, PJ, VP, AP, EMN, KA, TP, MN, MT, KN, JH, LW, ES, AO, SN, VH, GD, CC, DE contributed to the reclassification of data from their respective countries, and gave input on statistical analyses, interpretation of results and drafting of the article. TB, AH, HV, PW, MCBR, PF, EL, NS gave input on the statistical analyses, interpretation of results and drafting of the manuscript. The other co-authors were local EPIC collaborators involved in the design of the study and data collection. ER is the overall coordinator of the EPIC study. All co-authors provided comments and suggestions on the article and approved the final version. Results: Between countries, the mean percentage of dietary supplement use varied almost 10-fold among women and even more among men. There was a clear north-south gradient in use, with a higher consumption in northern countries. The lowest crude mean percentage of use was found in Greece (2.0% among men, 6.7% among women), and the highest was in Denmark (51.0% among men, 65.8% among women). Use was higher in women than in men. Vitamins, minerals or combinations of them were the predominant types of supplements reported, but there were striking differences between countries. Conclusions: This study indicates that there are wide variations in supplement use in Europe, which may affect individual and population nutrient intakes. The results underline the need to monitor consumption of dietary supplements in Europe, as well as to evaluate the risks and benefits.