Application of Seemingly Unrelated Regression in Medical Data with Intermittently Observed Time-Dependent Covariates
Joint Authors
Pakfetrat, Maryam
Zare, Najaf
Ayatollahi, Seyyed Mohammad Taghi
Keshavarzi, Sareh
Source
Computational and Mathematical Methods in Medicine
Issue
Vol. 2012, Issue 2012 (31 Dec. 2012), pp.1-11, 11 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2012-12-18
Country of Publication
Egypt
No. of Pages
11
Main Subjects
Abstract EN
Background.
In many studies with longitudinal data, time-dependent covariates can only be measured intermittently (not at all observation times), and this presents difficulties for standard statistical analyses.
This situation is common in medical studies, and methods that deal with this challenge would be useful.
Methods.
In this study, we performed the seemingly unrelated regression (SUR) based models, with respect to each observation time in longitudinal data with intermittently observed time-dependent covariates and further compared these models with mixed-effect regression models (MRMs) under three classic imputation procedures.
Simulation studies were performed to compare the sample size properties of the estimated coefficients for different modeling choices.
Results.
In general, the proposed models in the presence of intermittently observed time-dependent covariates showed a good performance.
However, when we considered only the observed values of the covariate without any imputations, the resulted biases were greater.
The performances of the proposed SUR-based models in comparison with MRM using classic imputation methods were nearly similar with approximately equal amounts of bias and MSE.
Conclusion.
The simulation study suggests that the SUR-based models work as efficiently as MRM in the case of intermittently observed time-dependent covariates.
Thus, it can be used as an alternative to MRM.
American Psychological Association (APA)
Keshavarzi, Sareh& Ayatollahi, Seyyed Mohammad Taghi& Zare, Najaf& Pakfetrat, Maryam. 2012. Application of Seemingly Unrelated Regression in Medical Data with Intermittently Observed Time-Dependent Covariates. Computational and Mathematical Methods in Medicine،Vol. 2012, no. 2012, pp.1-11.
https://search.emarefa.net/detail/BIM-500863
Modern Language Association (MLA)
Keshavarzi, Sareh…[et al.]. Application of Seemingly Unrelated Regression in Medical Data with Intermittently Observed Time-Dependent Covariates. Computational and Mathematical Methods in Medicine No. 2012 (2012), pp.1-11.
https://search.emarefa.net/detail/BIM-500863
American Medical Association (AMA)
Keshavarzi, Sareh& Ayatollahi, Seyyed Mohammad Taghi& Zare, Najaf& Pakfetrat, Maryam. Application of Seemingly Unrelated Regression in Medical Data with Intermittently Observed Time-Dependent Covariates. Computational and Mathematical Methods in Medicine. 2012. Vol. 2012, no. 2012, pp.1-11.
https://search.emarefa.net/detail/BIM-500863
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-500863