Statistical analyses
Descriptive statistics were used for summarizing patient and transplant characteristics. Overall survival (OS) was defined as the duration of time from transplant to time of death or the date of the last follow-up reported to the CIBMTR database. The Kaplan-Meier method was used to estimate overall survival and the log-rank test was used to examine the effect of acute and chronic GVHD on overall survival. Odds ratio (OR) analysis was used to identify factors associated with the development of aGVHD grade III/IV. Analyses were performed with SPSSĀ® statistical program version 25-26 (IBM Corp., Armonk, N.Y., USA) and R Core Team, 2020.