I am currently performing DE analysis starting from raw counts from an RNA-seq experiment using the Limma Voom script included in UseGalaxy and I would like to introduce age and sex as co-variates in the differential expression analysis.
In the menu “input information from factor file?”, I have clicked yes and attached a txt file in which I have introduced the groups that I am interested in comparing in the second column, sex (coded as a discrete variable using 0 and 1) in the third column and age in the fourth column.
The script runs perfectly but I am not sure if I can introduce age like this, as age is a continuous and not a discrete variable.
Could someone confirm me if I am proceeding the right way?
If not, could anyone tell me the best way to proceed?
Many thanks in advance.