The repeatability evaluates the consistency and reliability of the results, ensuring that there is minimal deviation or variability in the analysis. The repeatability of our HILIC-MS/MS method was determined by measuring the RSD of endogenous acyl-CoA species in QC samples. It was found that out of 19 targets, 7 species show RSD below 5% . The RSD of (5-10) % and (10-15)