Estimated probability of induction failure for each day delaying chemotherapy initiation. (A-D) Estimated adjusted probability of induction failure. Interaction between TDT and age and interaction between TDT and WBC were significant, and analyses were stratified by age (>60 vs ≤60 years) and WBC (>50 vs ≤50 G/L). (A-B) Estimated probability of induction failure in subjects with WBC ≤50 G/L for each value of TDT, adjusted** for the mean of all other variables of the model in (A) younger patients (≤60 years, n = 276) and (B) older patients (>60 years, n = 190). The locations of the 3 knots used in the RCS method are 3, 9, and 35 days (corresponding, respectively, to the 10th, 50th, and 90th percentile of the TDT).²²  **Adjusted for ECOG performance status (OR = 1.75, 95% CI: 0.98-3.13, P = .058; OR = 2.81, 95% CI: 1.32-5.99, P = .007; and OR = 4.64, 95% CI: 1.17-18.39, P = .029, respectively, for ECOG 1, 2, and 3/4 vs 0), secondary AML (OR = 1.65; 95% CI: 0.99-2.74; P = .053 compared with de novo AML), ELN classification (OR = 2.06, 95% CI: 0.85-4.98, P = .107; OR = 3.83, 95% CI: 1.64-8.94, P = .002; and OR = 4.70, 95% CI: 2.00-11.04, P < .001, respectively, for intermediate I, intermediate II, and adverse vs favorable), and the interaction between TDT and age (>60 vs ≤60 years). (C-D) Estimated probability of induction failure in subjects with WBC >50 G/L for each value of TDT, adjusted*** for the mean of all other variables of the model in (C) younger patients (≤60 years, n = 82) and (D) older patients (>60 years, n = 51). The locations of the 3 knots used in the RCS method are 1, 2, and 10 days (corresponding, respectively, to the 10th, 50th, and 90th percentile of TDT).²²  ***Adjusted for ECOG performance status (OR = 4.55, 95% CI: 0.56-36.7, P = .155; OR = 7.57, 95% CI: 0.76-74.9, P = .084; and OR = 4.75, 95% CI: 0.33-68.7, P = .253, respectively, for ECOG 1, 2, and 3/4 vs 0), secondary AML (OR = 20.57; 95% CI: 4.32-97.8; P < .001 compared with de novo AML), ELN classification (OR = 8.53, 95% CI: 2.17-33.5, P = .002; OR = 3.04, 95% CI: 0.66-14.0, P = .154; and OR = 4.94, 95% CI: 0.83-29.6, P = .080, respectively, for intermediate I, intermediate II, and adverse vs favorable), and the interaction between TDT and age (>60 vs ≤60 years).