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Penalized full likelihood approach to variable selection for Cox's regression model under nested case-control
Jie-Huei Wang1,2, Chun-Hao Pan2, I-Shou Chang3,4
1Division of Biostatistics and Bioinformatics, Institute of Population Health Science, National Health Research Institutes, 35, Keyan Rd., Zhunan Town, Miaoli County, 35053, Taiwan.
This study introduces a penalized full likelihood approach for variable selection in nested case-control (NCC) studies. The proposed method, penalized non-parametric maximum likelihood estimates (PNPMLE), demonstrates superior performance over existing techniques for risk estimation and covariate identification.
Area of Science:
- Biostatistics
- Epidemiology
- Statistical Modeling
Background:
- Nested case-control (NCC) sampling is an efficient design for case-control studies within a cohort.
- Variable selection is crucial for identifying risk factors in epidemiological research.
- Existing methods like weighted partial likelihood may have limitations in estimating relative risks and selecting covariates under NCC sampling.
Purpose of the Study:
- To develop a penalized full likelihood approach for variable selection in NCC studies.
- To evaluate the performance of penalized non-parametric maximum likelihood estimates (PNPMLE) compared to weighted partial likelihood.
- To establish theoretical properties and practical estimation methods for the proposed PNPMLE.
Main Methods:
- Utilized Cox's regression model within a penalized full likelihood framework.
- Derived self-consistency equations for penalized non-parametric maximum likelihood estimates (PNPMLE).
- Employed a cross-validation method based on profile likelihood for tuning parameter selection.
- Investigated the performance of LASSO and SCAD penalties, with SCAD showing better results for larger cohorts.
Main Results:
- PNPMLE showed better performance than weighted partial likelihood in estimating log-relative risk and identifying covariates under NCC sampling.
- LASSO penalty performed best for small cohort sizes, while SCAD performed best for large cohort sizes.
- The SCAD penalty established consistency, asymptotic normality, and oracle properties for PNPMLE, along with sparsity.
- A consistent estimate of asymptotic variance using observed profile likelihood was proposed.
Conclusions:
- The penalized full likelihood approach using PNPMLE is a robust method for variable selection in NCC studies.
- The SCAD penalty offers desirable statistical properties, including oracle properties, for PNPMLE.
- The method was successfully applied to analyze liver cancer diagnosis in a type 2 diabetes mellitus dataset.
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