Can we use biomarkers in combination with self-reports to strengthen the analysis of nutritional epidemiologic studies?

Table 1 Parameters for the Lutein - Age Related Macular Degeneration Model

Model	Parameter	Value*
Biomarker-Diet^a	Intercept β ₀			5.29
	Slope β ₁			0.60
	Residual variance(ε _BL)			0.10
Biomarker Measurement^b	Mean(TBL)			5.60
	Variance(TBL)			0.19
	Residual variance(ε _MBL)			0.05
			FFQ		6 × 24 HR
	Intercept γ ₀		0.35		0.08
	Slope γ ₁		0.71		0.84
Dietary Intake Measurement^c	Mean(TDI)			0.51
	Variance(TDI)			0.25
	Residual variance(ε _RDI)		0.36		0.20
Disease-Diet^d		Model a		Model b		Model c
	Intercept α ₀	0.51		6.72		3.77
	Coefficient α ₁	-1.00		0.00		-0.48
	Coefficient α ₂	0.00		-1.20		-0.63

* Biomarker level is log transformed nmol/L; Dietary intake is log transformed mg/d. Parameter values are derived from data in references: Van het Hoff et al[26], Brevik et al[28], Delcourt et al[33], Dixon et al[30], Mares et al[31] and on unpublished data from the OPEN study[34], as described in Additional File 1: Appendix, Part A.
^a Parameters for regression of TBL on TDI
^b Parameters for regression of MBL on TBL
^c Parameters for regression of RDI on TDI
^d Parameters for regression of disease D on TBL and TDI