IFNA2 and chronic graft versus host disease: The cumulative incidences of all grades acute graft-versus-host disease (aGVHD), all grades chronic graft-versus-host disease (cGVHD), and severe cGVHD at 3 years after IFN-α therapy were 2.0% (95% confidence interval [CI], 0.3–3.8%), 53.2% (95% CI, 46.8–59.7%), and 6.2% (95% CI, 3.1–9.2%), respectively.