Analysis of MyPRS Control Sample stability over time. MyPRS Control Sample stability over time; (A) H929 Control sample GEP70 scores generated bewteen August 2012 and August 2013 exhitit high stability over time. No gradual shift up or down in risk score is observed. Standard deviation of risk scores in this analysies was 2.72 and a CV of 0.03. (B) Control sample data from September 2013 to February 2014 (new aliquot of H929) shows further improvements in assay stability. Standard deviation 1.70, CV 0.019.