Table 2.

Validity^a of the Self-Report Instruments and Plasma Marker for Total Carotenoids in a WHEL Sample of 3,088 Breast Cancer Survivors Recruited Between 1995 and 2000 and Followed Through 2006

Assessment Methodb and Years	Error Correlation in Repeated Plasma Measurements (r)
	r = 0				r = 0.3c
	Comparison (n = 1,551)		Intervention (n = 1,537)		Comparison (n = 1,551)		Intervention (n = 1,537)
	Validity Estimate	95% Credible Interval	Validity Estimate	95% Credible Interval	Validity Estimate	95% Credible Interval	Validity Estimate	95% Credible Interval
24-Hour recalls
Baseline	0.44	0.40, 0.48	0.44	0.40, 0.48	0.44	0.40, 0.47	0.44	0.40, 0.47
1 year	0.46	0.42, 0.49	0.56	0.52, 0.60	0.45	0.41, 0.48	0.55	0.51, 0.59
4 years	0.48	0.44, 0.52	0.58	0.54, 0.62	0.49	0.45, 0.53	0.57	0.54, 0.61
Arizona food frequency questionnaire
Baseline	0.39	0.35, 0.43	0.39	0.35, 0.43	0.38	0.34, 0.42	0.38	0.34, 0.42
1 year	0.42	0.38, 0.46	0.53	0.49, 0.57	0.41	0.37, 0.45	0.52	0.48, 0.56
4 years	0.42	0.38, 0.46	0.57	0.53, 0.61	0.42	0.38, 0.46	0.57	0.53, 0.61
Plasma
Baseline	0.85	0.82, 0.86	0.85	0.82, 0.86	0.87	0.84, 0.90	0.87	0.84, 0.90
1 year	0.90	0.88, 0.93	0.93	0.91, 0.95	0.90	0.87, 0.93	0.93	0.91, 0.96
4 years	0.87	0.85, 0.90	0.91	0.89, 0.93	0.87	0.84, 0.89	0.91	0.89, 0.93

Abbreviation: WHEL, Women's Healthy Eating and Living.

^a“Validity” is defined as the correlation between observed and true dietary intake, reflecting the accuracy of the assessment method.

^bSelf-reported dietary intakes adjusted for body mass index and total caloric intake; plasma markers adjusted for plasma cholesterol and body mass index.

^cAssumed first-order autoregressive correlation structure for plasma error matrix.