RT Journal Article SR Electronic T1 In response to: Helicopter versus ground ambulance: review of national database for outcomes in survival in transferred trauma patients in the USA Michaels D, Pham H, Puckett Y, et al Trauma Surg Acute Care Open 2019;4:e000211 JF Trauma Surgery & Acute Care Open JO Trauma Surg Acute Care Open FD BMJ Publishing Group Ltd SP e000404 DO 10.1136/tsaco-2019-000404 VO 4 IS 1 A1 Dowd, Brianna A1 Elkbuli, Adel YR 2019 UL http://tsaco.bmj.com/content/4/1/e000404.abstract AB