Reproducibility and relative validity of a food frequency questionnaire to estimate intake of dietary phylloquinone and menaquinones.
S R ZwakenbergA I P EngelenG W DalmeijerS L BoothC VermeerJ J M M DrijversM C OckeE J M FeskensYvonne T van der SchouwJ W J BeulensPublished in: European journal of clinical nutrition (2017)
The FFQ is reproducible to rank subjects for phylloquinone and menaquinone intake.The relative validity of our FFQ, compared with 24HDR, to estimate intake of phylloquinone and short-chain menaquinones was low, but the relative validity for long-chain menaquinones was good. The relative validity of our FFQ, compared with plasma phylloquinone and dpucMGP, was relatively low for both phylloquinone and menaquinone intake.