title: Perceived subject outcomes and impact on health-related quality of life associated with diet using the new Food Benefits Assessment (FBA) questionnaire: development and psychometric validation.
abstract: OBJECTIVE
  To assess the perceived outcomes associated with diet/food intake in the general adult population.
  
  
  METHODS
  The Food Benefits Assessment (FBA) questionnaire was developed from subjects' verbatim transcripts (n 18) and after comprehension tests (n 5). Normal-weight (n 130) and overweight (n 67) subjects then completed the final questionnaire twice, 7 d apart. Psychometric properties were assessed, including construct validity by principal components analysis (PCA), concurrent validity (Spearman coefficient) with the Short Form-36 scale (SF-36), known-group validity by comparing FBA dimension scores according to lifestyle and clinical variables, internal consistency reliability (Cronbach's alpha) and test-retest reproducibility in stable subjects over 1 week (intraclass correlation coefficient, ICC).
  
  
  RESULTS
  PCA and Multitrait analysis confirmed the final version of the FBA comprising forty-one items split into seven dimensions (vitality; digestive comfort; physical appearance; well-being; snacking; disease prevention; aesthetics). All dimensions displayed good item convergent validity (0.44 to 0.80), good concurrent validity (highest correlation between well-being dimension of FBA and mental health scale of SF-36, r=0.83) and good known-group validity and reproducibility (ICC >or= 0.76); internal consistency reliability was good to excellent (Cronbach's alpha=0.79 to 0.91).
  
  
  CONCLUSIONS
  The FBA is the first valid and reliable questionnaire that allows the assessment of diet effects and impact as perceived by subjects. It is a good candidate in the nutrition field for further use in specific population settings and with a particular food or daily diet. Linguistically validated English (UK and US) and German versions of the questionnaire are available.
authors.affiliation: Danone Research, RD 128, F-91767 Palaiseau Cedex, France. denis.guyonnet@danone.com
authors.forename: Denis
authors.initials: D
authors.lastname: Guyonnet
authors.forename: Olivier
authors.initials: O
authors.lastname: Chassany
authors.forename: Céline
authors.initials: C
authors.lastname: Picard
authors.forename: Isabelle
authors.initials: I
authors.lastname: Guillemin
authors.forename: Juliette
authors.initials: J
authors.lastname: Meunier
authors.forename: Eva
authors.initials: E
authors.lastname: Seignobos
authors.forename: Marc
authors.initials: M
authors.lastname: Vigneux
authors.forename: Taous
authors.initials: T
authors.lastname: Lassel
authors.forename: Elyse
authors.initials: E
authors.lastname: Trudeau
mesh_terms: D000328:Adult; D000368:Aged; D004032:Diet / Q000523:psychology*; D005260:Female; D058870:Food, Organic; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D025341:Principal Component Analysis; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D012647:Self-Assessment; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D011795:Surveys and Questionnaires / Q000592:standards*; D055815:Young Adult