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Figure 2 | BMC Medical Research Methodology

Figure 2

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

Figure 2

Simulation Extrapolation (SIMEX) plot of corrected coefficients for model with 3H as the exposure and Word Fluency Test (WFT) decline as the outcome: two approaches; ARIC (1987–98)1. w: 3H; x: 6H; _cons: intercept in the model: Logit(Y = 1) = _cons + β naive1Q1(3H) + β naive2Q1(6H) where Y = decline in Word Fluency Test (WFT) based on the RCI < -1.645 criterion. Lambda: scale factors used to add error to the error-prone variable Q1. Error variance (needed for the SIMEX procedure) is estimated internally using Approach A: {Q1, M/N} or Approach B: {Q1, Q2/Q3}.

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