Relative contributions of parameters that contribute to progression to myelofibrosis (MF), acute myeloid leukemia (AML), and death. (Reprinted from Grinfeld J, Nangalia J, Baxter EJ, et al. Classification and Personalized Prognosis in Myeloproliferative Neoplasms. N Engl J Med. 2018;379:1416-1430.)