1 Professor, Faculty of Health Sciences, The University of Sydney and Northern Sydney Local Health District, St Leonards, Sydney, NSW, Australia; Adjunct Professor, Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; j.elliott@northwestern.edu.
2 Associate Professor, Department of Emergency Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL; dmarkcourtney@gmail.com.