The adjusted probability of overall survival after double UCB transplantation (infused TNC of both units was < 2.5 × 10⁷/kg [group 1], infused TNC of unit 1 was < 2.5 × 107/kg and unit 2, ≥ 2.5 × 10⁷/kg [group 2] and infused TNC of both units was ≥ 2.5 × 10⁷/kg [group 3]) and adequately dosed single UCB unit transplantation. The 2-year probabilities of overall survival were 37% (95% CI, 27-46), 36% (95% CI, 25-46), and 33% (95% CI, 21-46) after group 1, 2, and 3 double UCB transplantations, respectively, and 34% (95% CI, 24-45) after single UCB transplantation, adjusted for disease status at transplantation.