Table 1

Folate intake (μg/day) assessed by the dietary records and food frequency questionnaire, and their correlation coefficients.

DR1
 FFQ2
Spearman correlation



Mean ± SD
 Median
 Range
 Mean ± SD
 Median
 Range
 % difference of mean
 Crude
 Energy-adjusted3
 Deattenuated
Cohort I









     Men (n = 102)
 425 ± 103
 427
 210–735
 473 ± 231
 444
 119–1807
 11
 0.49
 0.40
 0.57
     Women (n = 113)
 389 ± 106
 380
 153–667
 476 ± 287
 419
 146–1978
 22
 0.29
 0.35
 0.47











Cohort II









     Men (n = 174)
 467 ± 156
 443
 197–1280
 421 ± 190
 370
 85–1178
 -10
 0.33
 0.50
 0.63
     Women (n = 176)
 426 ± 112
 417
 198–980
 454 ± 237
 397
 4–1498
 7
 0.42
 0.48
 0.63

1 DR, dietary records

2 FFQ, food frequency questionnaire.

3 Folate was adjusted for total energy intake using the residual method.

Ishihara et al. Nutrition Journal 2005 4:26   doi:10.1186/1475-2891-4-26