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Risk Ratio Estimation in Longitudinal Studies
Seyedeh Solmaz Talebi1, Kazem Mohammad1, Aliakbar Rasekhi2
1Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
Archives of Iranian Medicine
|March 2, 2019
Summary
For longitudinal studies, the COPY method effectively estimates risk ratios (RR) when outcomes are common, outperforming traditional log-binomial regression and offering a reliable alternative to odds ratios.
Area of Science:
- Medical and Interventional Sciences
- Behavioral Sciences
- Epidemiological Research
Background:
- Longitudinal studies frequently employ risk ratio (RR) estimation.
- Log-binomial regression, a common method for RR, often encounters convergence issues.
- Odds ratios provide inaccurate RR estimates for common outcomes in cohort studies.
Purpose of the Study:
- To introduce and evaluate two methods for risk ratio estimation in longitudinal data: the COPY method and modified log-Poisson regression.
- To address the limitations of existing methods for risk ratio estimation in longitudinal studies.
Main Methods:
- Illustration of the COPY method and modified log-Poisson regression for risk ratio estimation.
- Utilizing an unpublished simulation study to assess method performance.
Main Results:
- The COPY method demonstrated strong performance in risk ratio estimation, showing closeness to true values (low mean square error).
- Modified log-Poisson regression was also presented as an alternative.
Conclusions:
- The COPY method is recommended for risk ratio estimation in longitudinal data settings, particularly when outcomes are common.
- These methods offer practical solutions for accurate risk assessment in longitudinal research.
Keywords:
COPY methodGeneralized estimation equationsLongitudinal dataModified log-Poisson regressionRisk ratioMore Related Videos
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