Skip to main content

Table 2 Correlation coefficients of energy and nutrient intakes from dietary records and food frequency questionnaire for Japanese athletes. (n = 78)

From: Development and validation of a food frequency questionnaire for Japanese athletes (FFQJA)

Nutrient intake   DR FFQJA Correlation coefficient
Median (Interquartile range) Median (Interquartile range) Crude (95% CI) Energy-adjusted (95% CI) ICC (95% CI)
Energy (kcal) 2560 (2074, 2962) 2502 (2073, 3391) 0.523 (0.324–0.678) 0.466 (0.273–0.623)
Protein (g) 91.1 (72.9, 102.5) 94.5 (73.1, 117.0) 0.445 (0.234–0.616) 0.314 (0.090–0.508) 0.393 (0.188–0.565)
Fat (g) 80.8 (65.1, 98.2) 73.6 (58.4, 89.3) 0.344 (0.122–0.533) 0.270 (0.043–0.470) 0.338 (0.126–0.521)
Carbohydrate (g) 347.9 (273.0, 400.4) 374.0 (308.6, 510.9) 0.550 (0.356–0.699) 0.353 (0.132–0.541) 0.470 (0.278–0.626)
Calcium (mg) 509 (415, 670) 573 (432, 803) 0.379 (0.160–0.562) 0.584 (0.397–0.724) 0.367 (0.207–0.578)
Iron (Fe) (mg) 8.2 (6.8, 9.9) 8.2 (6.2, 10.4) 0.436 (0.223–0.609) 0.491 (0.397–0.724) 0.409 (0.207–0.578)
Retinol (ηgRAE) 511 (397, 733) 586 (410, 1094) 0.407 (0.191–0.585) 0.515 (0.286–0.653) 0.351 (0.140–0.531)
Vitamin B1 (mg) 1.28 (1.02, 1.58) 1.29 (0.99, 1.77) 0.399 (0.182–0.579) 0.293 (0.286–0.653) 0.369 (0.161–0.546)
Vitamin B2 (mg) 1.34 (1.08, 1.60) 1.53 (1.10, 1.89) 0.473 (0.266–0.639) 0.574 (0.314–0.672) 0.433 (0.234–0.597)
Vitamin C (mg) 109 (77, 154) 126 (71, 170) 0.273 (0.046–0.473) 0.464 (0.067–0.490) 0.256 (0.036–0.451)
Dietary fiber (g) 13.6 (11.9, 16.7) 13.4 (10.6, 16.6) 0.222 (−0.006–0.428) 0.500 (0.385–0.717) 0.213 (−0.009–0.415)
  1. n = 78
  2. DR Dietary records, FFQJA Food frequency questionnaire for Japanese athletes, RAE retinol activity equivalents
  3. Crude correlation coefficient: Spearman’s correlation coefficients
  4. Energy-adjusted correlation coefficients were calculated using an energy density method
  5. ICC intraclass correlation coefficients
  6. 95% CI: 95% confidence interval