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Ensemble Classifiers for Predicting HIV-1 Resistance from Three Rule-Based Genotypic Resistance Interpretation Systems


Resistance to antiretrovirals (ARVs) is a major problem faced by HIV-infected individuals. Different rule-based algorithms were developed to infer HIV-1 susceptibility to antiretrovirals from genotypic data. However, there is discordance between them, resulting in difficulties for clinical decisions about which treatment to use. Here, we developed ensemble classifiers integrating three interpretation algorithms: Agence Nationale de Recherche sur le SIDA (ANRS), Rega, and the genotypic resistance interpretation system from Stanford HIV Drug Resistance Database (HIVdb). Three approaches were applied to develop a classifier with a single resistance profile: stacked generalization, a simple plurality vote scheme and the selection of the interpretation system with the best performance. The strategies were compared with the Friedman’s test and the performance of the classifiers was evaluated using the F-measure, sensitivity and specificity values. We found that the three strategies had similar performances for the selected antiretrovirals. For some cases, the stacking technique with naïve Bayes as the learning algorithm showed a statistically superior F-measure. This study demonstrates that ensemble classifiers can be an alternative tool for clinical decision-making since they provide a single resistance profile from the most commonly used resistance interpretation systems.

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We want to acknowledge FAPERJ (Carlos Chagas Filho Foundation for Research Support of the State of Rio de Janeiro), CNPq Brazil (National Counsel of Technological and Scientific Development) and CAPES (Coordination for the Improvement of Higher-Education Personnel) for the financial support provided for this research.


Letícia Raposo is funded by Carlos Chagas Filho Foundation for Research Support of the State of Rio de Janeiro (FAPERJ, grant 221,340) and was funded by National Counsel of Technological and Scientific Development (CNPq Brazil, grant 131,968/2012–2).

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Correspondence to Letícia M. Raposo.

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Raposo, L.M., Nobre, F.F. Ensemble Classifiers for Predicting HIV-1 Resistance from Three Rule-Based Genotypic Resistance Interpretation Systems. J Med Syst 41, 155 (2017).

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