Reproducibility and relative validity of a brief quantitative food frequency questionnaire for assessing fruit and vegetable intakes in N orth‐ A frican women

Abstract Background In the context of a rapidly increasing prevalence of noncommunicable diseases, fruit and vegetables could play a key preventive role. To date, there is no rapid assessment tool available for measuring the fruit and vegetable intakes of N orth‐ A frican women. The present study aimed to investigate the reproducibility and relative validity of an eight‐item quantitative f ood f requency q uestionnaire that measures the fruit and vegetable intakes ( FV ‐ FFQ ) of M oroccan women. Methods During a 1‐week period, 100 women, living in the city of R abat, M orocco (aged 20–49 years) completed the short FV ‐ FFQ twice: once at baseline ( FV ‐ FFQ 1) and once at the end of the study ( FV ‐ FFQ 2). In the mean time, participants completed three 24‐h dietary recalls. All questionnaires were administered by interviewers. Reproducibility was assessed by computing Spearman's correlation coefficients, i ntra c lass c orrelation ( ICC ) coefficients and k appa statistics. Relative validity was assessed by computing W ilcoxon signed‐rank tests and S pearman's correlation coefficients, as well as by performing B land– A ltman plots. Results In terms of reproducibility, S pearman's correlation coefficient was 0.56; ICC coefficient was 0.68; and weighted k appa was 0.35. In terms of relative validity, compared with the three 24‐h recalls, the FV ‐ FFQ slightly underestimated mean fruit and vegetable intakes (−10.9%; P = 0.006); Spearman's correlation coefficient was 0.69; at the individual level, intakes measured by the FV ‐ FFQ were between 0.39 and 2.19 times those measured by the 24‐h recalls. Conclusions The brief eight‐item FV ‐ FFQ is a reliable and relatively valid tool for measuring mean fruit and vegetable intakes at the population level, although this is not the case at the individual level.