18 ‘Tell me what’s happened’: when linguistic choices affect efficiency of ambulance dispatch for cardiac arrest

Abstract

Aim

Clear and efficient communication between emergency caller and call-taker is crucial to timely ambulance dispatch. Within the Medical Priority Dispatch System,¹ the first opportunity that callers have of describing the situation is after the scripted prompt “okay, tell me exactly what happened”. However, in 60% cases, call-takers introduce a slight linguistic variation (what’s happened v. what happened). This study analyses the effect of this change on the way callers describe the emergency.

Methods

Using a mixed-methods analysis combining Conversation Analysis and Corpus Linguistics, we analysed 184 calls from paramedic-confirmed out-of-hospital cardiac arrests in Perth (Western Australia) in 2014–2015. We coded each call for its use of tense in the prompt and the format of the response as either a report (focusing on symptoms) or a narrative² (containing irrelevant background details) and we timed the callers’ responses.

Results

The use of report response was much more frequent when call-takers chose the present perfect (what’s happened) rather than the simple past (what happened) (72% v. 43%, p<0.0001). We found that the median length of caller response was significantly shorter when it was structured as a report rather than a narrative (9 v. 18 s, p<0.0001). Reports unfolded more efficiently over a median of 3 turns (v. 6 for narratives, p<0.0001).

Conclusion

A change of tense can impact how efficiently callers describe a time-critical emergency. Our results suggest that a better understanding of linguistic and interactional dynamics can improve dispatch performance.

References

• Medical Priority Dispatch System (version 12.1.3). Salt Lake City, Utah, USA: Priority Dispatch Corp.

• Labov W, Waletzky J. Narrative analysis: Oral sessions of personal experience. In: Helm J, editor. Essays Verbal Vis. Arts, Seattle: University of Washington Press; 2003, p. 74–104.

Conflict of interest

A. Whiteside and D. Brink receive full salary support, and P. Bailey, M. Inoue and J. Finn receive partial salary support from St John Ambulance.

Funding

Funding for this research was received from an Australian NHMRC (National Health and Medical Research Centre) Partnership Project: #1076949 ‘Improving ambulance dispatch to time-critical emergencies’. J. Finn and J. Bray receive partial salary support from the NHMRC ‘Aus-ROC’ Centre for Research Excellence #1029983. J. Bray receives salary support from an NHMRC/NHF (National Heart Foundation) Early Career Fellowship.