TY - JOUR

T1 - Relative validity and reproducibility of a food frequency questionnaire to assess dietary fiber intake in Danish adults

AU - Vuholm, Stine

AU - Lorenzen, Janne Kunchel

AU - Kristensen, Mette Bredal

N1 - CURIS 2014 NEXS 408

PY - 2014

Y1 - 2014

N2 - Background: Differences in habitual dietary fiber intake may modify effects of dietary fiber interventions, thus measurement of habitual dietary fiber intake is relevant to apply in intervention studies on fiber-rich foods, and food frequency questionnaire (FFQ) is a commonly used method. Rye bread is the major contributor of dietary fiber in the Danish population, and a nation-specific FFQ is therefore needed.Objective: The aim of this study was to assess the relative validity and reproducibility of a self-administered quantitative FFQ designed to assess total dietary fiber intake among Danish adults.Design: In order to assess the relative validity of the FFQ, a total of 125 participants completed both a 7-day weighed dietary recording (DR) and an FFQ consisting of 60 questions. To evaluate the reproducibility of theFFQ, a sub-group of 12 participants subsequently completed an FFQ approximately 6 months later.Results: Estimates of mean dietary fiber intake were 24.999.8 and 28.199.4 g/day when applying the FFQ and DR, respectively, where FFQ estimates were 12% lower (pB0.001). Pearson’s correlation coefficient between the estimated dietary fiber intake of the two methods was r0.63 (pB0.001), and 62% of theparticipants were grouped into the same tertile of intake according to the two methods. The estimates of mean dietary intake of first and second FFQ were very similar (22.294.0 and 23.394.1 g/day, respectively, p0.42) and showed a correlation of r0.95 (95% CI 0.830.99).Conclusion: The developed FFQ showed moderate underestimation of dietary fiber intake (g/day), adequate ranking of subjects according to their dietary fiber intake, and good reproducibility. The FFQ is therefore believed to be a valuable tool for epidemiology and screening in human interventions, where intake of dietary fibers is of specific interest.

AB - Background: Differences in habitual dietary fiber intake may modify effects of dietary fiber interventions, thus measurement of habitual dietary fiber intake is relevant to apply in intervention studies on fiber-rich foods, and food frequency questionnaire (FFQ) is a commonly used method. Rye bread is the major contributor of dietary fiber in the Danish population, and a nation-specific FFQ is therefore needed.Objective: The aim of this study was to assess the relative validity and reproducibility of a self-administered quantitative FFQ designed to assess total dietary fiber intake among Danish adults.Design: In order to assess the relative validity of the FFQ, a total of 125 participants completed both a 7-day weighed dietary recording (DR) and an FFQ consisting of 60 questions. To evaluate the reproducibility of theFFQ, a sub-group of 12 participants subsequently completed an FFQ approximately 6 months later.Results: Estimates of mean dietary fiber intake were 24.999.8 and 28.199.4 g/day when applying the FFQ and DR, respectively, where FFQ estimates were 12% lower (pB0.001). Pearson’s correlation coefficient between the estimated dietary fiber intake of the two methods was r0.63 (pB0.001), and 62% of theparticipants were grouped into the same tertile of intake according to the two methods. The estimates of mean dietary intake of first and second FFQ were very similar (22.294.0 and 23.394.1 g/day, respectively, p0.42) and showed a correlation of r0.95 (95% CI 0.830.99).Conclusion: The developed FFQ showed moderate underestimation of dietary fiber intake (g/day), adequate ranking of subjects according to their dietary fiber intake, and good reproducibility. The FFQ is therefore believed to be a valuable tool for epidemiology and screening in human interventions, where intake of dietary fibers is of specific interest.

U2 - 10.3402/fnr.v58.24723

DO - 10.3402/fnr.v58.24723

M3 - Journal article

VL - 58

JO - Scandinavian Journal of Nutrition/Naringsforskning, Supplement

JF - Scandinavian Journal of Nutrition/Naringsforskning, Supplement

SN - 1102-6510

M1 - 24723

ER -