Not really - in the case I'm talking about they are sending out a car/helicopter (depending on practicality/timings) to arrive on scene within <20 mins, with a specialist registrar/consultant level doctor with extensive A&E experience, and a paramedic, who can provide a much more comprehensive trauma response than the best equipped ambulance service cover. Taking A&E to the patient, with the ability to perform selected roadside operations, administer anaesthetics, induce comas, take the patient quickly to the most suitable trauma/major-trauma hospital, bypass the A&E doctor when reaching the hospital (having made these diagnosis themselves). Which for the selected trauma parients to whom Control deem time-critical/severe enough is a good service, paid for by charitable donation.
When patients arrive at the designated hospital a 'handover' is given to the trauma team, who make a definitive diagnosis with the aid of CT scanning and ultrasound as per Bastion field hospital. The response team give a presumptive diagnosis based on the scene of the incident and the injuries found, and initial management given to the patient.