Reproducibility and validity of food group intake in a short food frequency questionnaire for the middle-aged Japanese population

Nahomi Imaeda, Chiho Goto, Tae Sasakabe, Haruo Mikami, Isao Oze, Akihiro Hosono, Mariko Naito, Naoko Miyagawa, Etsuko Ozaki, Hiroaki Ikezaki, Hinako Nanri, Noriko T. Nakahata, Sakurako K. Kamano, Kiyonori Kuriki, Yuri T. Yaguchi, Takamasa Kayama, Ayako Kurihara, Sei Harada, Kenji Wakai