Are prehospital deaths from trauma and accidental injury preventable? A summary report 23 5 Key findings Literature review At the start of the research, a systematic literature review was conducted to examine the heterogeneity in terminology and methodology across studies into preventable prehospital trauma deaths (see Oliver and Walter 2016 for the full report). This review revealed inconsistencies in both the methodologies employed and the terminology used to define ‘preventable’ deaths. The studies were also inconsistent in their inclusion of those dead at the scene or dead on arrival in their analysis. These inconsistencies affirmed for the authors that no key research could be used as a comparator to the revised 1994 study (study one). They also concluded that research into preventability in the therapeutic vacuum, which occurs prehospital (before professional intervention), will be inhibited without homogeneity in the methodologies and terminologies of prevention. There is, therefore, a need for the research community to reach consensus on prevention in the prehospital space.