70 [high fat diet]) was negligible (kappa statistic = 0.036). The MF was accurate at the extremes of fat intake, but could not reliably identify the 3 AHA dietary classifications. Alternative MF cutpoints of <30 (Step 2), 30–50 (Step 1), and >50 (high fat diet) were highly sensitive (96%), but had low specificity (46%) for a high fat diet. ROC curve analysis identified that a MF score cutoff of 38 provided optimal sensitivity 75% and specificity 72%, and had modest agreement (kappa = 0.39, P < 0.001) with the FFQ for the identification of subjects with a high fat diet. Conclusions The MEDFICTS questionnaire is most suitable as a tool to identify high fat diets, rather than discriminate AHA Step 1 and Step 2 diets. Currently recommended MEDFICTS cutpoints are too high, leading to overestimation of dietary quality. A cutpoint of 38 appears to be providing optimal identification of patients who do not meet AHA dietary guidelines for fat intake."/>
Block Dietary | High Fat | Step 1 | Step 2 | ANOVA | |
---|---|---|---|---|---|
Variable | Diet | Diet | Diet | F | Sig. |
Total calories | 1980 | 1540 | 1302 | 12.3 | .0001 |
% fat | 40.9 | 38 | 30.3 | 10.1 | .0001 |
% saturated fat | 15.7 | 13.1 | 10.6 | 22.1 | .0001 |
Cholesterol | 351 | 309 | 181 | 5.3 | .006 |