title: Online dietary intake estimation: the Food4Me food frequency questionnaire.
abstract: BACKGROUND
  Dietary assessment methods are important tools for nutrition research. Online dietary assessment tools have the potential to become invaluable methods of assessing dietary intake because, compared with traditional methods, they have many advantages including the automatic storage of input data and the immediate generation of nutritional outputs.
  
  
  OBJECTIVE
  The aim of this study was to develop an online food frequency questionnaire (FFQ) for dietary data collection in the "Food4Me" study and to compare this with the validated European Prospective Investigation of Cancer (EPIC) Norfolk printed FFQ.
  
  
  METHODS
  The Food4Me FFQ used in this analysis was developed to consist of 157 food items. Standardized color photographs were incorporated in the development of the Food4Me FFQ to facilitate accurate quantification of the portion size of each food item. Participants were recruited in two centers (Dublin, Ireland and Reading, United Kingdom) and each received the online Food4Me FFQ and the printed EPIC-Norfolk FFQ in random order. Participants completed the Food4Me FFQ online and, for most food items, participants were requested to choose their usual serving size among seven possibilities from a range of portion size pictures. The level of agreement between the two methods was evaluated for both nutrient and food group intakes using the Bland and Altman method and classification into quartiles of daily intake. Correlations were calculated for nutrient and food group intakes.
  
  
  RESULTS
  A total of 113 participants were recruited with a mean age of 30 (SD 10) years (40.7% male, 46/113; 59.3%, 67/113 female). Cross-classification into exact plus adjacent quartiles ranged from 77% to 97% at the nutrient level and 77% to 99% at the food group level. Agreement at the nutrient level was highest for alcohol (97%) and lowest for percent energy from polyunsaturated fatty acids (77%). Crude unadjusted correlations for nutrients ranged between .43 and .86. Agreement at the food group level was highest for "other fruits" (eg, apples, pears, oranges) and lowest for "cakes, pastries, and buns". For food groups, correlations ranged between .41 and .90.
  
  
  CONCLUSIONS
  The results demonstrate that the online Food4Me FFQ has good agreement with the validated printed EPIC-Norfolk FFQ for assessing both nutrient and food group intakes, rendering it a useful tool for ranking individuals based on nutrient and food group intakes.
authors.affiliation: UCD Institute of Food and Health, University College Dublin, Dublin, Ireland.
authors.forename: Hannah
authors.initials: H
authors.lastname: Forster
authors.forename: Rosalind
authors.initials: R
authors.lastname: Fallaize
authors.forename: Caroline
authors.initials: C
authors.lastname: Gallagher
authors.forename: Clare B
authors.initials: CB
authors.lastname: O'Donovan
authors.forename: Clara
authors.initials: C
authors.lastname: Woolhead
authors.forename: Marianne C
authors.initials: MC
authors.lastname: Walsh
authors.forename: Anna L
authors.initials: AL
authors.lastname: Macready
authors.forename: Julie A
authors.initials: JA
authors.lastname: Lovegrove
authors.forename: John C
authors.initials: JC
authors.lastname: Mathers
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Gibney
authors.forename: Lorraine
authors.initials: L
authors.lastname: Brennan
authors.forename: Eileen R
authors.initials: ER
authors.lastname: Gibney
mesh_terms: D000328:Adult; D004032:Diet; D015930:Diet Records; D004034:Diet Surveys; D002149:Energy Intake; D005260:Female; D005502:Food; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D006113:United Kingdom
keywords: Food4Me; Web-based; dietary assessment; food frequency questionnaire; online dietary assessment tool