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Selecting Multiple Biomarker Subsets with Similarly Effective Binary Classification Performances
Published on: October 11, 2018
A comparison of biomarker based incidence estimators
Thomas A McWalter1, Alex Welte
1School of Computational and Applied Mathematics, University of the Witwatersrand, Johannesburg, South Africa. mcwalter@cam.wits.ac.za
Plos One
|October 8, 2009
Summary
The McWalter/Welte method is the most reliable for estimating HIV incidence using biomarker assays, even when accounting for imperfect specificity and individuals who do not progress on the test. This method offers unbiased results under various epidemic conditions.
Area of Science:
- Epidemiology
- Biostatistics
- Infectious Disease Modeling
Background:
- Biomarker assays, such as the BED assay, are cost-effective for estimating HIV incidence in cross-sectional surveys.
- Estimating HIV incidence is complicated by false positive results from biomarkers, leading to various statistical estimators.
- Handling imperfect specificity in biomarker assays is crucial for accurate HIV incidence estimation.
Purpose of the Study:
- To compare and analyze three different statistical estimators for HIV incidence: McDougal et al., Hargrove et al., and McWalter & Welte.
- To evaluate the performance of these estimators under conditions of imperfect specificity and varying epidemic states.
- To identify the most robust and unbiased method for HIV incidence estimation using biomarker data.
Main Methods:
- Comparative analysis of three HIV incidence estimators: McDougal et al., Hargrove et al., and McWalter & Welte.
- Mathematical derivation to show relationships between calibration parameters in the McDougal methodology.
- Testing estimators under a steady-state epidemic model, including individuals who fail to progress on the biomarker.
Main Results:
- An identity was established, simplifying the McDougal estimator to require only mean window period and long-term specificity calibration.
- All three estimators can be expressed using a common set of calibration parameters.
- Under steady-state epidemic conditions with non-progressors, only the McWalter/Welte method yielded an unbiased HIV incidence estimate.
Conclusions:
- The McWalter/Welte method is the most robust estimator, applicable under the least restrictive assumptions.
- The McDougal estimator can be simplified for easier calibration.
- The McWalter/Welte method demonstrates the least bias among the reviewed HIV incidence estimation techniques.
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