The reproducibility of 24-h dietary recall for estimating mineral intakes and their food sources among middle-aged Japanese men and women

The objective of the present study was to examine reproducibility for mineral intakes estimated by single 24-h dietary recall for middle-aged Japanese men and women. We conducted repeated cross-sectional study between 1973 and 1999. The subjects were 262 Japanese people (132 men and 130 women) aged 40-69 years. The median Spearman correlation coefficients (range) for mineral intakes were 0.43 (0.31-0.55) for men and 0.39 (0.32-0.50) for women. The correlation coefficients stratified by the survey periods 1973-1984 and 1985-1999 were 0.42 (0.31-0.53) for men and 0.44 (0.34-0.53) for women during the earlier period, and 0.43 (0.22-0.62) for men and 0.29 (0.21-0.65) for women during the later period. In conclusion, the reproducibility of single 24-h dietary recall was fairly good for estimating mineral intakes by middle-aged Japanese men and women, although the reproducibility for some minerals tended to decline from the mid-1980s.