Table 4.
Ability of Food Frequency Questionnaire (FFQ) to Identify People Not Meeting RDA for Nutrients or Recommendations for Cholesterol and Fat (n = 89), Berkeley, Calif, 2000
| Criterion | Percent of Sample Below the Criterion | Sensitivity, %c | Specificity, %d | |
|
| ||||
|---|---|---|---|---|
| In Recall,a % | In FFQ,b % | |||
| Below RDA | ||||
| Vitamin C | 18 | 19 | 50 | 88 |
| Iron | 63 | 61 | 77 | 67 |
| Calcium | 70 | 42 | 50 | 78 |
| Cholesterol <300 mg/day | 44 | 44 | 69 | 76 |
| Percentage of energy from fat <30% | 61 | 55 | 62 | 66 |
RDA indicates recommended dietary allowance.
a
Percentage of respondents who failed to meet the criterion, by three 24-hour recalls.
b
Percentage of respondents who failed to meet the criterion, by FFQ.
c
Of those identified by recalls as failing to meet the recommendations, the percentage correctly identified by FFQ.
d
Of those identified by recalls as meeting recommendations, the percentage correctly identified by FFQ.