Correction: Chaby et al. Cross-Platform Evaluation of Commercially Targeted and Untargeted Metabolomics Approaches to Optimize the Investigation of Psychiatric Disease. Metabolites 2021, 11, 609

In the original publication [...].


Figure Legend
In the original publication [1], there was a mistake in the legend for Figure 4, a log scale for the axis has been applied to each graph to better show the included data points.
The correct legend appears below: Figure 4. Platform-specific, log-transformed, average metabolite levels in control samples for vendors reporting absolute units; each point represents mean ± SEM for 11 control samples in total: 9 control samples from 6 individuals (with 3 technical replicates), and 2 NIST pooled reference plasma samples.Each panel depicts the range of covered metabolites, across all assays, for an exemplar metabolite class: (A) amino acids, (B) fatty acids, (C) lysophosphatidylcholines (LPC), (D) hydroxy acids, (E) ceramides, and (F) triglycerides.Depicted data are from the second sample shipment.NIST = concentrations reported in the National Institute of Standards and Technology (NIST) SRM 1950 Certificate of Analysis (COA, revised June 2020).

Error in Figure/Table
In the original publication, there was a mistake in: 1. Tables 1-3.The color coding in these tables does not match the footnote.This has been corrected.
2. Table 3.The amino acid, alanine, was omitted from the published manuscript.This is now included in the corrected table.
3. Table 3 as published.NIST standards were used for part of the study to compare the accuracy of the different measurements.In the measurement of fatty acids and cholesterol, the NIST standards reflect the total concentration of fatty acids and cholesterol.The vendors in the published manuscript were reporting free fatty acids and free cholesterol, and therefore the comparison represented in Table 3 is not valid.This discrepancy was brought to our attention after the paper was published.The fatty acid and cholesterol values and percent accuracy for Biocrates and Lipotype were removed.
4. Figure 4. Reflecting the updates from Table 3, Figure 4b has been edited and a log scale applied for all graphs in the figure to better show the included data points.
The corrected Tables 1-3 and Figure 4 appear below: 4. Figure 4. Reflecting the updates from Table 3, Figure 4b has been edited and a log scale applied for all graphs in the figure to better show the included data points.
The corrected Tables 1-3 and Figure 4 appear below.The authors state that the scientific conclusions are unaffected.This correction was approved by the Academic Editor.The original publication has also been updated.Notes: "High" precision is shown in green (≤10%), "moderate" in yellow (10% < x < 20%), and "low" in red (≥20%).

Figure 4 .
Figure 4. Platform-specific, log-transformed, average metabolite levels in control samples for vendors reporting absolute units; each point represents mean ± SEM for 11 control samples in total: 9 control samples from 6 individuals (with 3 technical replicates), and 2 NIST pooled reference plasma samples.Each panel depicts the range of covered metabolites, across all assays, for an exemplar metabolite class: (A) amino acids, (B) fatty acids, (C) lysophosphatidylcholines (LPC), (D) hydroxy acids, (E) ceramides, and (F) triglycerides.Depicted data are from the second sample shipment.NIST = concentrations reported in the National Institute of Standards and Technology (NIST) SRM 1950 Certificate of Analysis (COA, revised June 2020).

Figure 4 .
Figure 4. Platform-specific, log-transformed, average metabolite levels in control samples for vendors reporting absolute units; each point represents mean ± SEM for 11 control samples in total: 9 control samples from 6 individuals (with 3 technical replicates), and 2 NIST pooled reference plasma samples.Each panel depicts the range of covered metabolites, across all assays, for an exemplar metabolite class: (A) amino acids, (B) fatty acids, (C) lysophosphatidylcholines (LPC), (D) hydroxy acids, (E) ceramides, and (F) triglycerides.Depicted data are from the second sample shipment.NIST = concentrations reported in the National Institute of Standards and Technology (NIST) SRM 1950 Certificate of Analysis (COA, revised June 2020).

Table 2 .
Inter-assay percent Coefficient of Variance (CV%) within Metabolite Classes for Technical Replicates of PTSD and Control Samples across Shipment 1 and Shipment 2.