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Table 2 Attenuation factor estimates (with standard error) from the two approaches and regression calibrated odds ratio2: Bivariate logistic regression model; ARIC (1987–1998)1

From: Measurement error adjustment in essential fatty acid intake from a food frequency questionnaire: alternative approaches and methods

Fatty acid groups and ratios j 3 External validation with biomarkers (M/N) Internal repeat measurements (Q2/Q3)
  Attenuation factor λ ^ j MathType@MTEF@5@5@+=feaafiart1ev1aqatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacuWF7oaBgaqcamaaBaaaleaacqWGQbGAaeqaaaaa@3001@ Standard error (SE λ ^ j MathType@MTEF@5@5@+=feaafiart1ev1aqatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacuWF7oaBgaqcamaaBaaaleaacqWGQbGAaeqaaaaa@3001@ ) RCAL odds ratio (95% CI)2 Attenuation factor λ ^ j MathType@MTEF@5@5@+=feaafiart1ev1aqatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacuWF7oaBgaqcamaaBaaaleaacqWGQbGAaeqaaaaa@3001@ Standard error (SE λ ^ j MathType@MTEF@5@5@+=feaafiart1ev1aqatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacuWF7oaBgaqcamaaBaaaleaacqWGQbGAaeqaaaaa@3001@ ) RCAL odds ratio (95% CI)2
6p 0.230 (0.020) 20.3 (11.8, 35.0) 0.605 (0.031) 3.1 (2.7, 3.7)
3p 0.090 (0.022) >100 0.456 (0.033) 4.6 (3.5, 5.9)
6H 0.046 (0.028) >100 0.653 (0.027) 2.9 (2.6, 3.2)
3H 0.408 (0.020) 5.5 (4.5, 6.6) 0.717 (0.025) 2.6 (2.4, 2.9)
6 0.269 (0.020) 13.1 (8.8, 19.7) 0.603 (0.031) 3.2 (2.7, 3.7)
3 0.353 (0.021) 7.1 (5.5, 9.2) 0.632 (0.027) 3.0 (2.6, 3.4)
3p/6p 0.251 (0.021) 15.8 (9.8, 25.6) 0.588 (0.031) 3.2 (2.8, 3.8)
3H/6H 0.426 (0.020) 5.1 (4.3, 6,1) 0.655 (0.028) 2.9 (2.5, 3.2)
3/6 0.401 (0.021) 5.6 (4.6, 6.9) 0.655 (0.024) 2.9 (2.6, 3.2)
  1. 1 Q1: Food frequency questionnaire measurement at visit 1 of fatty acid group intake as % of energy intake or ratio of n-3 to n-6 groups. M: biomarker of fatty acid intake in cholesteryl ester fraction of plasma; N: biomarker of fatty acid intake in phospholipids fraction of plasma; Q2: Repeat of Q1 measured at visit 2 among a subset of the cohort; Q3: Repeat of Q1 measured at visit 3 among the surviving baseline cohort. RCAL: regression calibrated estimate.
  2. 2 Naïve odds ratio assumed to be equal to 2.00 (1.64, 2.43), with Loge(odds rationaive) = β naive = 0.693 with a SE(β naive) = 0.100, in the following bivariate model: E( Y | Q j ) = β ^ 0 + β ^ (naïve, j) Q j MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaacqqGfbqrcqqGOaakcqWGzbqwcqqG8baFcqWGrbqudaWgaaWcbaGaemOAaOgabeaakiabbMcaPGGaaiab=1da9GGaciqb+j7aIzaajaWaaSbaaSqaaiabbcdaWaqabaGccqWFRaWkcuGFYoGygaqcamaaBaaaleaacqqGOaakcqqGUbGBcqqGHbqycqqGVdW7cqqG2bGDcqqGLbqzcqqGSaalcqqGGaaicqqGQbGAcqqGPaqkaeqaaOGaemyuae1aaSbaaSqaaiabdQgaQbqabaaaaa@4AB8@ . The odds ratio is for any binary outcome (0,1) vs. fatty acid exposure expressed as a z-score (increase in odds of outcome for each 1 SD in fatty acid exposure). Refer to Eq. 4.1–4.4.
  3. 3 See table 2.