Exposure Assessment Methods
- Usual Dietary Intakes
- The NCI Method
- Details of the NCI Method
- Food Intakes, US Population, 2001-04
- Selected Intakes as Ratios of Energy Intake, US Population, 2001-04
- Selected Intakes of Energy from Empty Calories, US Population, 2001-04
- SAS Macros
- Further Information
- Fact Sheet (PDF, 258 KB)
Usual Dietary Intakes: Further Information
Importance of Estimating Usual Intake Distributions
Freedman LS, Midthune D, Carroll RJ, Krebs-Smith S, Subar AF, Troiano RP, Dodd K, Schatzkin A, Bingham SA, Ferrari P, Kipnis V. Adjustments to improve the estimation of usual dietary intake distributions in the population. J Nutr 2004 Jul;134(7):1836-43. Erratum in: J Nutr 2005 Jun;135(6):1524.
Importance of Accounting for Measurement Error in Estimating Diet-Health Relationships
Freedman LS, Schatzkin A, Midthune D, Kipnis V. Dealing with dietary measurement error in nutritional cohort studies. J Natl Cancer Inst 2011 Jul;103(14):1086-92.
Review of Methods
Dodd KW, Guenther PM, Freedman LS, Subar AF, Kipnis V, Midthune D, Tooze JA, Krebs-Smith SM. Statistical methods for estimating usual intake of nutrients and foods: a review of the theory. J Am Diet Assoc 2006 Oct;106(10):1640-50. Review.
The NCI Method
Estimating distributions of a single dietary component
Tooze JA, Midthune D, Dodd KW, Freedman LS, Krebs-Smith SM, Subar AF, Guenther PM, Carroll RJ, Kipnis V. A new statistical method for estimating the usual intake of episodically consumed foods with application to their distribution. J Am Diet Assoc 2006 Oct;106(10):1575-87.
Tooze JA, Kipnis V, Buckman DW, Carroll RJ, Freedman LS, Guenther PM, Krebs-Smith SM, Subar AF, Dodd KW. A mixed-effects model approach for estimating the distribution of usual intake of nutrients: the NCI method. Stat Med 2010 Nov 30;29(27):2857-68.
Estimating distributions of two or more dietary components
Freedman LS, Guenther PM, Dodd KW, Krebs-Smith SM, Midthune D. The population distribution of ratios of usual intakes of dietary components that are consumed every day can be estimated from repeated 24-hour recalls. J Nutr 2010 Jan;140(1):111-6.
Freedman LS, Guenther PM, Krebs-Smith SM, Dodd KW, Midthune D. A population's distribution of Healthy Eating Index–2005 component scores can be estimated when more than one 24-hour recall is available. J Nutr 2010 Aug;140(8):1529-34.
Zhang S, Krebs-Smith SM, Midthune D, Perez A, Buckman D, Kipnis V, Freedman LS, Dodd KW, Carroll RJ. Fitting a bivariate measurement error model for episodically consumed dietary components. Intl J Biostat 2011;7(1):Article 1.
Zhang S, Midthune D, Guenther PM, Krebs-Smith SM, Kipnis V, Dodd KW, Buckman DW, Tooze JA, Freedman L, Carroll RJ. A new multivariate measurement error model with zero-inflated dietary data, and its application to dietary assessment. Ann Appl Stat 2011 Jun;5(2B):1456-87.
Use of frequency information as a covariate in a model to estimate usual intakes
Subar AF, Dodd KW, Guenther PM, Kipnis V, Midthune D, McDowell M, Tooze JA, Freedman LS, Krebs-Smith SM. The food propensity questionnaire: concept, development, and validation for use as a covariate in a model to estimate usual food intake. J Am Diet Assoc 2006 Oct;106(10):1556-63.
Evaluating relationships between usual intakes and health outcomes
Kipnis V, Midthune D, Buckman DW, Dodd KW, Guenther PM, Krebs-Smith SM, Subar AF, Tooze JA, Carroll RJ, Freedman LS. Modeling data with excess zeros and measurement error: application to evaluating relationships between episodically consumed foods and health outcomes. Biometrics 2009 Dec;65(4):1003-10.
Combining self-report intake data with biomarker data
Freedman LS, Kipnis V, Schatzkin A, Tasevska N, Potischman N. Can we use biomarkers in combination with self-reports to strengthen the analysis of nutritional epidemiologic studies? Epidemiol Perspect Innov 2010 Jan;7(1):2.
Freedman LS, Tasevska N, Kipnis V, Schatzkin A, Mares J, Tinker L, Potsichman N. Gains in statistical power from using a dietary biomarker in combination with self-reported intake to strengthen the analysis of a diet-disease relationship – an example from CAREDS. Am J Epidemiol 2010 Oct; 172(7):836-42.
Last Modified: 18 Oct 2013