Erratum: Mattacola et al. (2019)

In the article Mattacola CG, Quintana C, Crots J, Tumlin KI, and Bonin S, Repeated Impacts Diminish the Impact Performance of Equestrian Helmets, J Sport Rehabil, 2019;28(4):368–372, https://doi.org/10.1123/jsr.2018-0355, the Troxel helmet was not identified as a prototype. In each occurrence, it has been corrected to read Troxel-prototype. In addition, two sentences were added to the text: (1) “The Troxel helmet, according to the manufacturer, was a prototype with a lower density liner.” (see third sentence of Methods section); (2) “We did not quantify liner densities of the tested helmets and therefore did not explore the relationship between liner density and peak headform acceleration.” (see paragraph 2, sentence 10 of the Discussion section). These corrections have been made in the online version of the article. The authors regret this error.