Evidence map›Paper›PMID 39930915›Full record

ArticleStatistical methods in medical research2025

Modeling the ratio of correlated biomarkers using copula regression.

Moritz Berger, Nadja Klein, Michael Wagner, Matthias Schmid

Abstract read
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Article in Statistical methods in medical research, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

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4 · The record

Corrections and comments

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5 · Who and what money

Authors and funding

4 authors.

Moritz BergerDepartment of Medical Biometry, Informatics and Epidemiology, Faculty of Medicine, University of Bonn, Bonn, Germany.ORCID 0000-0002-0656-5286
Nadja KleinScientific Computing Center, Karlsruhe Institute of Technology, Karlsruhe, Baden-Württemberg, Germany.ORCID 0000-0002-5072-5347
Michael WagnerGerman Center for Neurodegenerative Diseases Bonn, Nordrhein-Westfalen, Germany.
Matthias SchmidDepartment of Medical Biometry, Informatics and Epidemiology, Faculty of Medicine, University of Bonn, Bonn, Germany.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Modeling the ratio of two dependent components as a function of covariates is a frequently pursued objective in observational research. Despite the high relevance of this topic in medical studies, where biomarker ratios are often used as surrogate endpoints for specific diseases, existing models are commonly based on oversimplified assumptions, assuming e.g. independence or strictly positive associations between the components. In this paper, we overcome such limitations and propose a regression model where the marginal distributions of the two components are linked by a copula. A key feature of our model is that it allows for both positive and negative associations between the components, with one of the model parameters being directly interpretable in terms of Kendall's rank correlation coefficient. We study our method theoretically, evaluate finite sample properties in a simulation study and demonstrate its efficacy in an application to diagnosis of Alzheimer's disease via ratios of amyloid-beta and total tau protein biomarkers.

Indexed as

BiomarkersModels, StatisticalAlzheimer DiseaseAmyloid beta-PeptidesComputer SimulationHumansRegression Analysistau ProteinsAmyloid beta-PeptidesBiomarkerstau ProteinsCopula modeldistributional regressiongamma distributionnegative dependenceratio outcome

Identifiers

PMID39930915
PMCPMC12177203

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.