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Normalization techniques for PARAFAC modeling of urine metabolomics data

ABSTRACT: One of the body fluids often used in metabolomics studies is urine. The peak intensities of metabolites in urine are affected by the urine history of an individual resulting in dilution differences. This requires therefore normalization of the data to correct for such differences. Two normalization techniques are commonly applied to urine samples prior to their further statistical analysis. First, AUC normalization aims to normalize a group of signals with peaks by standardizing the area under the curve (AUC) within a sample to the median, mean or any other proper representation of the amount of dilution. The second approach uses specific end-product metabolites such as creatinine and all intensities within a sample are expressed relative to the creatinine intensity. Another way of looking at urine metabolomics data is by realizing that the ratios between peak intensities are the information-carrying features. This opens up possibilities to use another class of data analysis techniques designed to deal with such ratios: compositional data analysis. In this approach special transformations are defined to deal with the ratio problem. In essence, it comes down to using another distance measure than the Euclidian Distance that is used in the conventional analysis of metabolomics data. We will illustrate using this type of approach in combination with three-way methods (i.e. PARAFAC) to be used in cases where samples of some biological material are measured at multiple time points. Aim of the paper is to develop PARAFAC modeling of three-way metabolomics data in the context of compositional data and compare this with standard normalization techniques for the specific case of urine metabolomics data.

INSTRUMENT(S): API 5500 QTRAP (AB Sciex)

SUBMITTER: Radana Karlikova

PROVIDER: MTBLS290 | MetaboLights | 2017-05-11

REPOSITORIES: MetaboLights

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			Action	DRS
	MTBLS290	Other
	FILES	Other
	a_MTBLS290_parafac_modeling_metabolite_profiling_mass_spectrometry.txt	Txt
	i_Investigation.txt	Txt
	m_MTBLS290_parafac_modeling_metabolite_profiling_mass_spectrometry_v2_maf.tsv	Tabular

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Normalization techniques for PARAFAC modeling of urine metabolomics data

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