Evolution of performance scores before and after CBT. (A) Individual PS of patients with ≥12-month survival before and at last follow-up after CBT. (B-D) The δ of PS at 12 months and at last follow-up for MLD (B), GLD (C), and X-ALD (D). A positive δ is associated with decline in PS. Color coding for pre-CBT performance score is provided within each panel. FU, follow-up, n.a., not applicable.