Statistical analysis
REGRESSION
Metabolomics and lipidomics raw data were filtered out if missing values > 20% or relative standard deviation for pooled QC samples (QC-RSD) >15%. All data were then normalized using the QC-RLSC algorithm (PMID: 21720319) to eliminate the analytical variance generated during data acquisition. All statistical analyses were conducted with SAS software (version 9.4; SAS Institute Inc., Cary; North Carolina, USA) and R (version 4.0.2). Potential group differences were tested using the non-parametric Mann Whitney U test. FDR correcting for multiple testing with Benjamini-Hochberg procedure two-sided for p-values < 0.05 were regarded as statistically significant. The prediction models were constructed and fitted using logistic regression. The performance of the biomarker prediction panel is evaluated using the AUC (Area under the ROC Curve).