What is RSD and what do the Yenos RSD values mean?

RSD stands for Relative Standard Deviation — a measure of measurement variability expressed as a fraction of the mean. It is calculated as (standard deviation / mean) and is equivalent to the coefficient of variation (CV). RSD = 0.09 for cancer samples means that measurements of the cancer miRNA signal vary by about 9% around the mean of 1.83× HL. RSD = 0.17 for healthy samples means healthy measurements vary by about 17% around 1.04× HL. Even accounting for this variability, the distributions do not overlap: the lowest possible cancer value (approximately 1.83 - 3×0.09×1.83 = ~1.34) and the highest possible healthy value (approximately 1.04 + 3×0.17×1.04 = ~1.57) come very close but the published studies found zero actual overlap. The RSD values confirm the precision and consistency of the Yenos measurement.