Correction to: Validation of a novel patient reported tool to assess the impact of treatment in erythropoietic protoporphyria: the EPP-QoL - G. Biolcati; S. Hanneken; E. I. Minder; N. J. Neumann; J. H. P. Wilson; P. J. Wolgen; D. J. Wright; A. J. Lloyd (SpringerOpen, 2021)