Table 4.
Estimated correlation coefficients and attenuation factors between the FFQ and true intakes based on the 24 h dietary recalls using a measurement error model, unadjusted and adjusted for energy intake, in the calibration sub-study: the NIH–AARP Diet and Health Study, 1995–1996
| Correlation coefficient | Attenuation factor | |||
|---|---|---|---|---|
| Men | Women | Men | Women | |
| Total nitrate | ||||
| Unadjusted | 0·53 | 0·48 | 0·49 | 0·46 |
| Adjusted | 0·59 | 0·57 | 0·59 | 0·57 |
| Total nitrite | ||||
| Unadjusted | 0·45 | 0·37 | 0·32 | 0·24 |
| Adjusted | 0·59 | 0·58 | 0·47 | 0·38 |
| Animal nitrite | ||||
| Unadjusted | 0·61 | 0·47 | 0·49 | 0·44 |
| Adjusted | 0·64 | 0·52 | 0·56 | 0·54 |
| Plant nitrite | ||||
| Unadjusted | 0·52 | 0·48 | 0·40 | 0·30 |
| Adjusted | 0·68 | 0·68 | 0·54 | 0·44 |
NIH–AARP, National Institutes of Health–AARP.