We are running Network Analysis for sets of multivariable data.
Output_39_P1_87_081622.csv (7.6 KB)
Using the attached SAS output as an example. It is from a 2-group study. Mice (male, n=12 per group) were fed a control diet or a high-fat diet (HFD) for 12 weeks. At the end, liver was harvested and analyzed to see metabolomic differences between the 2 groups.
We identified 87 metabolites that met the criteria for statistical analysis. The “Raw_P” column showed 18 metabolites and the FDR column showed 5 metabolites that differed significantly between the two groups.
We understand that we can only use the metabolites that are significantly different between the two groups for network mapping.
Here are our questions.
- Should we use FDR (a list of 5) or “Raw_P” (a list of 18) to get a list of significant compounds?
- We noticed that the metabolic pathways identified by Global Network Analysis is presented in FDR-adjusted p-values. If we use the list of FDR-adjusted significant compounds (a list of 5) for analysis, our results will be “double FDR-adjusted” and findings seems to be conservative. Is it a correct approach?
Sincerely,
Lin Yan, Ph.D.
Grand Forks Human Nutr Res Ctr
ARS, USDA