Clinical risk model. (A) “Clinical” risk model for SM (n = 543) based on number of risk factors: (1) advanced SM vs ISM/SSM (HR, 2.7); (2) age >60 years (HR, 2.5); (3) platelets <150 × 10⁹/L (HR, 2.5); (4) anemia below sex-adjusted normal (HR, 2.2); and (5) serum ALP above normal range (HR, 2.1). HR (95% CI) values listed are calculated against the next lower risk level. (B-C) Application of the clinical risk model in advanced SM (n = 277) vs ISM/SSM (n = 266), respectively.