title: Dietary Assessment in the MetaCardis Study: Development and Relative Validity of an Online Food Frequency Questionnaire.
abstract: BACKGROUND
  The European study MetaCardis aims to investigate the role of the gut microbiota in health and cardiometabolic diseases in France, Germany, and Denmark. To evaluate long-term diet-disease relationships, a food frequency questionnaire (FFQ) was found to be the most relevant dietary assessment method for the MetaCardis study.
  
  
  OBJECTIVE
  The objectives of this study were to describe the development of three semiquantitative online FFQs used in the MetaCardis study-one FFQ per country-and to assess the relative validity of the French MetaCardis FFQ.
  
  
  METHODS
  The layout and format of the MetaCardis FFQ was based on the European Prospective Investigation of Cancer (EPIC)-Norfolk FFQ and the content was based on relevant European FFQs. Portion size and nutrient composition were derived from national food consumption surveys and food composition databases. To assess the validity of the French MetaCardis FFQ, a cross-sectional study design was utilized.
  
  
  METHODS
  The validation study included 324 adults recruited between September 2013 and June 2015 from different hospitals in Paris, France.
  
  
  METHODS
  Food intakes were measured with both the French MetaCardis FFQ and 3 consecutive self-administered web-based 24-hour dietary recalls (DRs).
  
  
  METHODS
  Several measures of validity of the French MetaCardis FFQ were evaluated: estimations of food groups, energy, and nutrient intakes from the DRs and the FFQ, Spearman and Pearson correlations, cross-classification, and Bland-Altman analyses.
  
  
  RESULTS
  The French MetaCardis FFQ tended to report higher food, energy, and nutrient intakes compared with the DRs. Mean correlation coefficient was 0.429 for food, 0.460 for energy, 0.544 for macronutrients, 0.640 for alcohol, and 0.503 for micronutrient intakes. Almost half of participants (44.4%) were correctly classified within tertiles of consumption, whereas 12.9% were misclassified in the opposite tertile. Performance of the FFQ was relatively similar after stratification by sex.
  
  
  CONCLUSIONS
  The French MetaCardis FFQ was found to have an acceptable level of validity and may be a useful instrument to rank individuals based on their food and nutrient intakes.
authors.forename: Eric O
authors.initials: EO
authors.lastname: Verger
authors.forename: Patrice
authors.initials: P
authors.lastname: Armstrong
authors.forename: Trine
authors.initials: T
authors.lastname: Nielsen
authors.forename: Rima
authors.initials: R
authors.lastname: Chakaroun
authors.forename: Judith
authors.initials: J
authors.lastname: Aron-Wisnewsky
authors.forename: Rikke Juul
authors.initials: RJ
authors.lastname: Gøbel
authors.forename: Tatjana
authors.initials: T
authors.lastname: Schütz
authors.forename: Fabien
authors.initials: F
authors.lastname: Delaere
authors.forename: Nicolas
authors.initials: N
authors.lastname: Gausseres
authors.forename: Karine
authors.initials: K
authors.lastname: Clément
authors.forename: Bridget A
authors.initials: BA
authors.lastname: Holmes
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D003718:Denmark; D004032:Diet; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D004041:Dietary Fats / Q000008:administration & dosage; D004044:Dietary Proteins / Q000008:administration & dosage; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage; D005260:Female; D005602:France; D005858:Germany; D006801:Humans; D020407:Internet; D008297:Male; D011939:Mental Recall; D008875:Middle Aged; D015596:Nutrition Assessment; D064787:Portion Size; D011446:Prospective Studies; D015203:Reproducibility of Results; D012646:Self Administration; D011795:Surveys and Questionnaires
chemical_list: D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins; D005231:Fatty Acids, Unsaturated
keywords: Development; Food frequency questionnaire; MetaCardis study; Portion sizes; Relative validity