Article Text

Original research
Efficacy of prehospital National Early Warning Score to predict outpatient disposition at an emergency department of a Japanese tertiary hospital: a retrospective study
  1. Takuro Endo1,2,
  2. Toru Yoshida1,
  3. Tomohiro Shinozaki3,
  4. Takako Motohashi4,
  5. Hsiang-Chin Hsu5,
  6. Shunsuke Fukuda1,
  7. Jumpei Tsukuda1,
  8. Takaki Naito1,
  9. Kenichiro Morisawa1,
  10. Nobuhiko Shimozawa1,
  11. Yasuhiko Taira1,
  12. Shigeki Fujitani1
  1. 1Department of Emergency and Critical Care Medicine, St Marianna University School of Medicine, Kawasaki, Kanagawa, Japan
  2. 2Department of Emergency Medicine, International University of Health and Welfare, Narita, Chiba, Japan
  3. 3Department of Information and Computer Technology, Faculty of Engineering, Tokyo University of Science, Katsushika-ku, Tokyo, Japan
  4. 4Department of Preventive Medicine, St Marianna University School of Medicine, Kawasaki, Kanagawa, Japan
  5. 5Emergency Medicine, National Cheng Kung University Hospital, Tainan, Taiwan
  1. Correspondence to Dr Shigeki Fujitani; shigekifujitani{at}


Objectives The National Early Warning Score (NEWS) was originally developed to assess hospitalised patients in the UK. We examined whether the NEWS could be applied to patients transported by ambulance in Japan.

Design This retrospective study assessed patients and calculated the NEWS from paramedic records. Emergency department (ED) disposition data were categorised into the following groups: discharged from the ED, admitted to the ward, admitted to the intensive care unit (ICU) or died in the ED. The predictive performance of NEWS for patient disposition was assessed using receiver operating characteristic curve analysis. Patient dispositions were compared among NEWS-based categories after adjusting for age, sex and presence of traumatic injury.

Setting A tertiary hospital in Japan.

Participants Overall, 2847 patients transported by ambulance between April 2017 and March 2018 were included.

Results The mean (±SD) NEWS differed significantly among patients discharged from the ED (n=1330, 3.7±2.9), admitted to the ward (n=1263, 6.3±3.8), admitted to the ICU (n=232, 9.4±4.0) and died in the ED (n=22, 11.7±2.9) (p<0.001). The prehospital NEWS C-statistics (95% CI) for admission to the ward, admission to the ICU or death in the ED; admission to the ICU or death in the ED; and death in the ED were 0.73 (0.72–0.75), 0.81 (0.78–0.83) and 0.90 (0.87–0.93), respectively. After adjusting for age, sex and trauma, the OR (95% CI) of admission to the ICU or death in the ED for the high-risk (NEWS ≥7) and medium-risk (NEWS 5–6) categories was 13.8 (8.9–21.6) and 4.2 (2.5–7.1), respectively.

Conclusion The findings from this Japanese tertiary hospital setting showed that prehospital NEWS could be used to identify patients at a risk of adverse outcomes. NEWS stratification was strongly correlated with patient disposition.

  • early warning scores
  • ambulance
  • prehospital

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  • Contributors TE, KM, ShiF and YT conceived the research idea and designed the study. TE, ShuF and TN collected the data. TE, TM, JT, TN, NS and TS provided statistical advice on study design and analysed the data. TE and ShiF chaired the data oversight committee. TE, HCH and TY drafted the first version of the manuscript. TE, ShiF and YT take public responsibility for the contents of this paper.

  • Funding This work was jointly funded by the St Marianna University School of Medicine Research Grant 2018 and the Yuumi Memorial Foundation for Home Health Care Grant 2017.

  • Competing interests None declared.

  • Patient consent for publication Not required.

  • Ethics approval The research protocol received approval from the ethics committee of the Institutional Review Board of St Marianna University School of Medicine (No 4325).

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data availability statement No data are available.

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