Comparison of change in prognostic power for specific scoring systems. (A) Change of Dxy with time for overall survival, and (B) change of Dxy with time for time to AML transformation (based on WHO-classified patients). The figure demonstrates that nearly all scores lost prognostic power over time, with the relative ranking remaining virtually unchanged. Scores with high initial prognostic power remained prognostically stronger than initially weaker scores. The prognostic power of the IPSS-R after about 9 months and of the IPSS-RA until around 14 months remains as high as that of the original IPSS at diagnosis (gray arrows). Inclusion of patient’s age results in higher initial prognostic power and better stability in predicting survival but not for time to AML progression represented by results from IPSS-RA and WPSS-A versions which included age (panel A).