Health-related quality of life and functional changes in DMD: A 12-month longitudinal cohort study

•At baseline, the PedsQLTM inventories correlated with almost all the functional measures.•There was a significant decrease between baseline and 12 months on PedsQLTM GCS.•This decrement paralleled with the decrement in the functional outcome measures.•PedsQLTM correlates with the level of impairment.•This correlations were not confirmed when 12 month changes are considered.