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BayesMetab: treatment of missing values in metabolomic studies using a Bayesian modeling approach
BACKGROUND: With the rise of metabolomics, the development of methods to address analytical challenges in the analysis of metabolomics data is of great importance. Missing values (MVs) are pervasive, yet the treatment of MVs can have a substantial impact on downstream statistical analyses. The MVs p...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
BioMed Central
2019
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6923847/ https://www.ncbi.nlm.nih.gov/pubmed/31861984 http://dx.doi.org/10.1186/s12859-019-3250-2 |
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author | Shah, Jasmit Brock, Guy N. Gaskins, Jeremy |
author_facet | Shah, Jasmit Brock, Guy N. Gaskins, Jeremy |
author_sort | Shah, Jasmit |
collection | PubMed |
description | BACKGROUND: With the rise of metabolomics, the development of methods to address analytical challenges in the analysis of metabolomics data is of great importance. Missing values (MVs) are pervasive, yet the treatment of MVs can have a substantial impact on downstream statistical analyses. The MVs problem in metabolomics is quite challenging and can arise because the metabolite is not biologically present in the sample, or is present in the sample but at a concentration below the lower limit of detection (LOD), or is present in the sample but undetected due to technical issues related to sample pre-processing steps. The former is considered missing not at random (MNAR) while the latter is an example of missing at random (MAR). Typically, such MVs are substituted by a minimum value, which may lead to severely biased results in downstream analyses. RESULTS: We develop a Bayesian model, called BayesMetab, that systematically accounts for missing values based on a Markov chain Monte Carlo (MCMC) algorithm that incorporates data augmentation by allowing MVs to be due to either truncation below the LOD or other technical reasons unrelated to its abundance. Based on a variety of performance metrics (power for detecting differential abundance, area under the curve, bias and MSE for parameter estimates), our simulation results indicate that BayesMetab outperformed other imputation algorithms when there is a mixture of missingness due to MAR and MNAR. Further, our approach was competitive with other methods tailored specifically to MNAR in situations where missing data were completely MNAR. Applying our approach to an analysis of metabolomics data from a mouse myocardial infarction revealed several statistically significant metabolites not previously identified that were of direct biological relevance to the study. CONCLUSIONS: Our findings demonstrate that BayesMetab has improved performance in imputing the missing values and performing statistical inference compared to other current methods when missing values are due to a mixture of MNAR and MAR. Analysis of real metabolomics data strongly suggests this mixture is likely to occur in practice, and thus, it is important to consider an imputation model that accounts for a mixture of missing data types. |
format | Online Article Text |
id | pubmed-6923847 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | BioMed Central |
record_format | MEDLINE/PubMed |
spelling | pubmed-69238472019-12-30 BayesMetab: treatment of missing values in metabolomic studies using a Bayesian modeling approach Shah, Jasmit Brock, Guy N. Gaskins, Jeremy BMC Bioinformatics Research BACKGROUND: With the rise of metabolomics, the development of methods to address analytical challenges in the analysis of metabolomics data is of great importance. Missing values (MVs) are pervasive, yet the treatment of MVs can have a substantial impact on downstream statistical analyses. The MVs problem in metabolomics is quite challenging and can arise because the metabolite is not biologically present in the sample, or is present in the sample but at a concentration below the lower limit of detection (LOD), or is present in the sample but undetected due to technical issues related to sample pre-processing steps. The former is considered missing not at random (MNAR) while the latter is an example of missing at random (MAR). Typically, such MVs are substituted by a minimum value, which may lead to severely biased results in downstream analyses. RESULTS: We develop a Bayesian model, called BayesMetab, that systematically accounts for missing values based on a Markov chain Monte Carlo (MCMC) algorithm that incorporates data augmentation by allowing MVs to be due to either truncation below the LOD or other technical reasons unrelated to its abundance. Based on a variety of performance metrics (power for detecting differential abundance, area under the curve, bias and MSE for parameter estimates), our simulation results indicate that BayesMetab outperformed other imputation algorithms when there is a mixture of missingness due to MAR and MNAR. Further, our approach was competitive with other methods tailored specifically to MNAR in situations where missing data were completely MNAR. Applying our approach to an analysis of metabolomics data from a mouse myocardial infarction revealed several statistically significant metabolites not previously identified that were of direct biological relevance to the study. CONCLUSIONS: Our findings demonstrate that BayesMetab has improved performance in imputing the missing values and performing statistical inference compared to other current methods when missing values are due to a mixture of MNAR and MAR. Analysis of real metabolomics data strongly suggests this mixture is likely to occur in practice, and thus, it is important to consider an imputation model that accounts for a mixture of missing data types. BioMed Central 2019-12-20 /pmc/articles/PMC6923847/ /pubmed/31861984 http://dx.doi.org/10.1186/s12859-019-3250-2 Text en © The Author(s). 2019 Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. |
spellingShingle | Research Shah, Jasmit Brock, Guy N. Gaskins, Jeremy BayesMetab: treatment of missing values in metabolomic studies using a Bayesian modeling approach |
title | BayesMetab: treatment of missing values in metabolomic studies using a Bayesian modeling approach |
title_full | BayesMetab: treatment of missing values in metabolomic studies using a Bayesian modeling approach |
title_fullStr | BayesMetab: treatment of missing values in metabolomic studies using a Bayesian modeling approach |
title_full_unstemmed | BayesMetab: treatment of missing values in metabolomic studies using a Bayesian modeling approach |
title_short | BayesMetab: treatment of missing values in metabolomic studies using a Bayesian modeling approach |
title_sort | bayesmetab: treatment of missing values in metabolomic studies using a bayesian modeling approach |
topic | Research |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6923847/ https://www.ncbi.nlm.nih.gov/pubmed/31861984 http://dx.doi.org/10.1186/s12859-019-3250-2 |
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