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Related Experiment Video

Updated: Jul 9, 2026

'Boden Food Plate': Novel Interactive Web-based Method for the Assessment of Dietary Intake

'Boden Food Plate': Novel Interactive Web-based Method for the Assessment of Dietary Intake

Published on: September 18, 2018

Correlations between estimated and true dietary intakes.

Gary E Fraser¹, David J Shavlik

¹Center for Health Research, School of Public Health, Loma Linda University, Loma Linda, CA 92350, USA. gfraser@sph.llu.edu

Annals of Epidemiology

|April 7, 2004

Summary

This study introduces a new method to estimate correlations between dietary assessment tools and true intake. Results show reference methods generally correlate better with true intake than questionnaires, highlighting potential issues with regression calibration.

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Area of Science:

Nutritional epidemiology
Biostatistics
Dietary assessment methodology

Background:

Accurate dietary intake assessment is crucial for nutritional research.
Current dietary assessment methods, like food frequency questionnaires and reference methods, have limitations in correlating with true intake.
The validity of these methods is often difficult to quantify due to complex error structures.

Purpose of the Study:

To develop and describe a statistical method for estimating correlations between dietary assessment tools and true dietary intake.
To assess the relative validity of food frequency questionnaires versus reference methods.
To investigate the correlation between errors in questionnaire and reference dietary data.

Main Methods:

Developed an error model incorporating data from a food frequency questionnaire (Q), a reference method (R), and a biological marker (M).
The model allows for non-classical error structures for R and M, and does not assume zero correlation between errors in Q and R.
Credible intervals were calculated for correlations between R, Q, M, true dietary data (T), and errors in R and Q.

Main Results:

Applied the model to a validation dataset, finding correlations between dietary data and true intake generally ranged from 0.4 to 0.8.
Correlations between the reference method and true intake (R,T) typically exceeded those of the questionnaire and true intake (Q,T), suggesting higher validity for R.
Estimated correlations between errors in R and Q were frequently non-zero, indicating potential problems with regression calibration using imperfect reference data.

Conclusions:

Integrating a biological marker with dietary data enables the calculation of correlations between estimated and true dietary intakes under reasonable error assumptions.
Sensitivity analyses are recommended for individual variables within the model.
The findings underscore the importance of estimating error correlations for accurate dietary assessment validation.