title: Response to letter to the editor.
authors.forename: Uta
authors.initials: U
authors.lastname: Roentgen
authors.forename: Gert Jan
authors.initials: GJ
authors.lastname: Gelderblom
authors.forename: Luc
authors.initials: L
authors.lastname: de Witte
mesh_terms: D002183:Canes; D005260:Female; D006801:Humans; D008297:Male; D012656:Self-Help Devices; D019987:Persons with Visual Disabilities; D016138:Walking