Table 1 Participant inclusion criteria (published in protocol paper [17])

Lay public callers

999 callers during the six trial weeks where the incident involved major trauma (defined as per below)

All 999 callers during observed shifts that involved trauma and were screened by HEMS dispatchers or Advanced Paramedic Practitioners in Critical Cares (APP-CCs) who attempted to use GoodSAM during the call

N/A

EOC staff

All CCPs, HEMS dispatchers, and Research Paramedics

All HEMS dispatchers and APP-CCs

All CCPs and HEMS dispatchers

Trauma patients

All trauma patients during the six trial observation weeks who were the subject of 999 calls involving major trauma, judged by the HEMS dispatcher and/or CCPs as likely to require enhanced dispatch

All trauma patients during observed shifts that involved trauma and were screened by HEMS dispatchers or APP-CCs who attempted to use GoodSAM during the call

N/A