title: Concurrent and construct validity of Mediterranean diet scores as assessed by an FFQ.
abstract: OBJECTIVE
  The aim of the present study was to assess the concurrent and construct validity of two diet-quality indices, a modified Mediterranean diet score (mMDS) and a Mediterranean-like diet score (MLDS) additionally incorporating unhealthy food choices, as determined by an FFQ.
  
  
  METHODS
  A validation study assessing FFQ intake estimates compared with ten or more unannounced 24 h recalls. Pearson's correlation coefficients, intraclass correlation coefficients (ICC), Bland-Altman plots and the limits of agreement method were used to assess the between-method agreement of scores. Construct validity was shown using associations between nutrient intakes derived from multiple 24 h recalls and the mMDS and MLDS derived from the FFQ.
  
  
  METHODS
  Gerona, Spain.
  
  
  METHODS
  A total of 107 consecutively selected participants from a population-based cross-sectional survey.
  
  
  RESULTS
  Pearson's correlations for the energy-adjusted mMDS and MLDS compared with multiple recalls were 0·48 and 0·62, respectively. The average FFQ energy-adjusted mMDS and MLDS were 102 % and 98 % of the recall-based mMDS and MLDS estimates, respectively. The FFQ under- and overestimated dietary recall estimates of the energy-adjusted MLDS by 28 % and 25 %, respectively, with slightly wider boundaries for the mMDS (31 % and 34 %). The ICC, which assesses absolute agreement, was similar to Pearson's correlations (mMDS = 0·48 and MLDS = 0·61). The mean differences between methods were similar across the range of average ratings for both scores, indicating the absence of bias. The FFQ-derived mMDS and MLDS correlated in the anticipated directions with intakes of eleven (73·3 %) and thirteen of fifteen nutrients (86·7 %), respectively.
  
  
  CONCLUSIONS
  The FFQ provides valid estimates of diet quality as assessed by the mMDS and MLDS.
authors: Cardiovascular Risk and Nutrition Research Group (CARIN-ULEC), IMIM-Hospital del Mar Barcelona, Biomedical Research Park (Parc de Recerca Biomèdica de Barcelona - PRBB), c/Doctor Aiguader 88, 08003 Barcelona, Spain.
authors: Alejandra A
authors: AA
authors: Benítez-Arciniega
authors: Michelle A
authors: MA
authors: Mendez
authors: Jose M
authors: JM
authors: Baena-Díez
authors: Maria-Asunción
authors: MA
authors: Rovira Martori
authors: Cristina
authors: C
authors: Soler
authors: Jaume
authors: J
authors: Marrugat
authors: Maria-Isabel
authors: MI
authors: Covas
authors: Hector
authors: H
authors: Sanz
authors: Alba
authors: A
authors: Llopis
authors: Helmut
authors: H
authors: Schröder
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D038441:Diet, Mediterranean; D002149:Energy Intake; D005247:Feeding Behavior; D005260:Female; D058870:Food, Organic; D006801:Humans; D016014:Linear Models; D008297:Male; D011939:Mental Recall; D008875:Middle Aged; D015596:Nutrition Assessment; D015203:Reproducibility of Results; D013030:Spain; D011795:Surveys and Questionnaires