Validation of the National Early Warning Score in the prehospital setting

Can the prehospital National Early Warning Score identify patients most at risk from subsequent deterioration?

“…However, as the documented observations were objective standard measurements, we have no reason to believe that they would have yielded different scores had they been calculated prospectively. The argument that our methodology is unlikely to have impacted the validity of our study is further strengthened by the similar findings reported in Silcock et al ’s prospective study, which reported an association between high NEWS and incidence of adverse outcomes 17. A prospective methodology may have been helpful in reducing the number of missing observations recorded on the ambulance service paperwork, which resulted in small sample sizes for some patient disposition groups (those admitted to the ITU or who died in the ED).…”

“…This study, conducted in Scotland, reported an association between elevated NEWS and a higher incidence of adverse outcomes, demonstrating its ability to identify high-risk patients at an early stage 17. Our study, the first to be conducted in an English ambulance service, aims to contribute to the limited body of evidence by examining whether prehospital NEWS can indicate subsequent hospital discharge disposition.…”

Strengths and limitations of early warning scores: A systematic review and narrative synthesis

“…46 The system has also proved valuable in the prehospital setting. 47,48 Challen and Walter describe how early warning scores can help to safely divert patients from the ED to alternative care providers. 49 However, another study amongst the ambulance service showed no effect of MEWS implementation on transportation or revisit rates.…”

A Comparison of the Ability of the Physiologic Components of Medical Emergency Team Criteria and the U.K. National Early Warning Score to Discriminate Patients at Risk of a Range of Adverse Clinical Outcomes*

“…The RCPL recommends that NEWS values of >7 should prompt assessment by an RRT (9). NEWS demonstrates better ability than other published EWSS to discriminate patients at risk of a range of clinical outcomes (6) and has been validated outside its development site (10)(11)(12)(13).…”