Association between time and cause-specific hazard of cGVHD. (A) Estimate of HR of NIH cGVHD-IS as a function of HCT date modeled as a continuous nonlinear variable (N = 3066), with HR relative to 1 January 2005; green line, unadjusted HR; red line, adjusted HR. (B) HR of relapse as a function of HCT date modeled as a continuous nonlinear variable among patients with malignant disease (n = 2756), with HR relative to 1 January 2005; green line, unadjusted HR; red line, adjusted HR.