Comparative survival using the different prognostic scoring systems (PSSs). Kaplan-Meyer survival curves in primary myelofibrosis based on the different PSSs: (A) WHO classification and European consensus for BMF grading^13,14 ; (B) Mayo PSS¹² ; (C) Dingli PSS¹² ; (D) Cervantes PSS¹⁰ ; and (E) Dupriez PSS.¹¹  Using the WHO classification and European consensus for BMF grading, CIMF-0 showed significantly better survival than CIMF-3, and CIMF-1/2 (grouped) showed significantly better survival than CIMF-3; using the Mayo,¹²  Dingli,¹²  and Dupriez¹¹  PSSs, there were no differences between the intermediate- and high-risk classes (the Cervantes PSS¹⁰  identifies only 2 risk classes).