Risk group analysis. Forest plots of the HR for DFS (A) and OS (B) of patients with ALL in CR1; donor versus no-donor, split by risk group, and the overall estimate together with 95% CI. The percentage reduction is equal to 100 × (1 HR). Poor risk was defined by: (1) cytogenetic abnormalities t(9;22), t(4;11), or t(1;19); (2) pro–B-cell immunophenotype; (3) high WBC (ie, > 30 × 10⁹/L in case of B-ALL; > 100 × 10⁹/L in case of T-ALL); and (4) late CR1 (ie, beyond 4 weeks from start induction). All other patients were classified in the standard-risk group. The pooled estimates of the HR of donor availability for all patients were, respectively, 0.60 (95% CI 0.41-0.87; P = .007) for DFS and 0.69 (95% CI 0.46-1.02; P = .06) for OS.