Corrigendum to "A pragmatic parallel group implementation study of a prehospital-activated ECPR protocol for refractory out-of-hospital cardiac arrest". [Resuscitation 167 (2021) 22–28]. (December 2021) - Grunau, Brian; Bashir, Jamil; Cheung, Anson; Boone, Robert; McDonald, Ken; Scheuermeyer, Frank; Singer, Joel; Jenneson, Sandra; Straight, Ron; Twaites, Brian; Harris, Luke; Haig, Scott; et al.