Development of a Food-Frequency Questionnaire to Measure the Dietary Calcium Intake of Adult Japanese Women
YUHO SATO, JUNKO TAMAKI,1 FUJIKO KITAYAMA,2 YUKINORI KUSAKA,3 YUMI KODERA,4 AKIKO KOUTANI5 and MASAYUKI IKI1
Department of Nutrition, Tenshi College School of Nursing and Nutrition, Sapporo, 1Department of Public Health, Kinki University School of Medicine, Osaka, 2Nutrient Control Room, Medical Service Section, University of Fukui Hospital, Fukui, 3Department of Environmental Health, University of Fukui Faculty of Medical Sciences, Fukui, 4Health Promotion Section, Fukui Health and Welfare Center, Fukui, 5Nutritional Management Room, Fukui Prefectural Hospital, Fukui, Japan
Assessing calcium intake is necessary for epidemiological studies on osteoporosis. This study was aimed at developing a valid food frequency questionnaire (FFQ) to estimate the dietary calcium intake of Japanese people. The FFQ contains 26 items, representing common sources of calcium. The respondents, 74 women aged 15 - 79 years living in Fukui city, whose dietary calcium intake was estimated at 638 ± 306 (S.D.) mg based on a one-day weighted food record kept during the National Nutrition Survey of 1996, were asked to indicate their consumption frequency and usual portion size (large, medium, small) for each food item. Trained dieticians interviewed the subjects to confirm their answers to the FFQs. The mean calcium intake per day according to the FFQ (655 ± 222 mg) did not differ significantly from that according to the one-day food record. The coefficient of correlation between these methods was 0.512, a statistically significant value. The calcium intake from dairy products showed a good correlation, r = 0.717. The coefficient of correlation between the values estimated based on two FFQ filled out three days apart was 0.900, showing good test-retest reliability. Therefore, this FFQ is valid and reliable in estimating dietary calcium intake for epidemiological studies.
keywords ——calcium; diet; food; nutrition; nutrition surveys
© 2005 Tohoku University Medical Press
===============================
Tohoku J. Exp. Med., 2005, 207, 217-222
Correspondence: Yuho Sato, Kita-13, Higashi-3, Higashi-ku, Sapporo 065-0013, Japan.
e-mail: y-satou@tenshi.ac.jp