Skip to main content
. 2012 Jan 24;175(4):340–347. doi: 10.1093/aje/kwr317

Figure 2.

Figure 2.

Comparison of statistical powers (%) when the use of a calibrated combination of 12 24-hour dietary recalls (24HRs) plus a food frequency questionnaire (FFQ) leads to 90% power, Eating at America’s Table Study, 1997–1998. The solid line shows results for calibrated 24HR(s) only. The dashed line shows results for a calibrated combination of 24HR(s) + FFQ. The dotted line shows results for the calibrated FFQ only. A) Energy-adjusted total fat intake; B) energy-adjusted vitamin C intake; C) energy-adjusted intake of whole grains; D) energy-adjusted intake of dark green vegetables. See Web Appendix 7 for plots for the other dietary components.