Skip Navigation
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Your Environment. Your Health.

Publication Detail

Title: Segmented regression in the presence of covariate measurement error in main study/validation study designs.

Authors: Staudenmayer, John; Spiegelman, Donna

Published In Biometrics, (2002 Dec)

Abstract: This article considers the problem of segmented regression in the presence of covariate measurement error in main study/validation study designs. First, we derive a closed and interpretable form for the full likelihood. After that, we use the likelihood results to compute the bias of the estimated changepoint in the case when the measurement error is ignored. We find the direction of the bias in the estimated changepoint to be determined by the design distribution of the observed covariates, and the bias can be in either direction. We apply the methodology to data from a nutritional study that investigates the relation between dietary folate and blood serum homocysteine levels and find that the analysis that ignores covariate measurement error would have indicated a much higher minimum daily dietary folate intake requirement than is obtained in the analysis that takes covariate measurement error into account.

PubMed ID: 12495141 Exiting the NIEHS site

MeSH Terms: Bias; Data Interpretation, Statistical*; Diet Records; Folic Acid/metabolism; Homocysteine/blood; Humans; Likelihood Functions*; Multivariate Analysis; Regression Analysis*; Reproducibility of Results; Surveys and Questionnaires

Back
to Top