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Robust and flexible inference for the covariate-specific receiver operating characteristic curve
Vanda Inácio1, Vanda M Lourenço2, Miguel de Carvalho1
1School of Mathematics, University of Edinburgh, Edinburgh, UK.
Statistics in Medicine
|September 1, 2021
Summary
This study introduces a robust statistical model to accurately assess diagnostic test performance, even with unusual results. The method enhances the reliability of receiver operating characteristic (ROC) curve analysis for medical research.
Area of Science:
- Biostatistics
- Medical Diagnostics
- Statistical Modeling
Background:
- Diagnostic tests are crucial in healthcare and research.
- Outlying test results can significantly impact the assessment of diagnostic test accuracy.
- Existing methods may not adequately handle atypical outcomes or nonlinear covariate effects.
Purpose of the Study:
- To develop a robust and flexible statistical model for covariate-specific receiver operating characteristic (ROC) curve inference.
- To safeguard against outlying test results in diagnostic test assessment.
- To accommodate nonlinear covariate effects in ROC analysis.
Main Methods:
- Postulated a location-scale regression model for test outcomes in diseased and non-diseased populations.
- Combined additive regression B-splines and M-estimation for regression function estimation.
- Estimated error distribution using a weighted empirical distribution function of standardized residuals.
Main Results:
- Simulation studies demonstrated successful recovery of the true covariate-specific area under the ROC curve under various contamination scenarios.
- The developed method proved robust to outlying test results.
- The model effectively handles nonlinear covariate effects.
Conclusions:
- The proposed robust statistical model provides reliable inference for covariate-specific ROC curves, even with outlying data.
- This approach enhances the accuracy of diagnostic test performance evaluation.
- Applied to prostate cancer data, the method assesses the Prostate Health Index's discriminatory ability and its age-related changes.
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