Kaplan-Meier estimates of OS based on complete or partial response at HSCT in the HLH-2004 study. Displayed are OS where death was defined as event. Five-year probabilities of survival (pSu) are indicated with a 95% CI. P values from Cox proportional hazards models. Complete response (CR) was defined as no fever, no splenomegaly, ANC ≥1.0 × 10⁹/L, platelets ≥100 × 10⁹/L, fibrinogen >1.5 g/L, and a ferritin cutoff of either <500 µg/L or <2000 µg/L (allowing missing information on one of the these parameters). Partial response (PR) was defined as having 3 to 5 normal parameters. (A) OS for the entire cohort based on CR (n = 42, events n = 10, blue line) or PR (n = 87, events n = 37, red line dashed); P = .035, using the ferritin cutoff of <500 µg/L. (B) OS for the entire cohort based on CR (n = 55, events n = 15, blue line) or PR (n = 76, events n = 31, red line dashed); P = .080, using the ferritin cutoff of <2000 µg/L.