Clinical assessment as a part of an early warning score-a Danish cluster-randomised, multicentre study of an individual early warning score.

BACKGROUND: The clinical benefit of Early Warning Scores (EWSs) is undocumented. Nursing staff's clinical assessment might improve the prediction of outcome and allow more efficient use of resources. We aimed to investigate whether the combination of clinical assessment and EWS would reduce the number of routine measurements without increasing mortality. METHODS: We did a cluster-randomised, crossover, non-inferiority study at eight hospitals in Denmark. Patients aged 18 years or older, admitted for more than 24 h were included. Admissions to paediatric or obstetric wards were excluded. The participating hospitals were randomly assigned 1:1 to start as either intervention or control with subsequent crossover. Primary outcomes were 30-day all-cause mortality (non-inferiority margin=0·5%) and average number of EWS per day per patient. The intervention was implementation of the Individual EWS (I-EWS), in which nursing staff can adjust the calculated score on the basis of their clinical assessment of the patient. I-EWS was compared with the National Early Warning Score (NEWS). The study is registered at ClinicalTrials.gov, NCT03690128 and is complete. FINDINGS: Unique admissions longer than 24 h were included from Oct 15, 2018 to Sept 30, 2019. Of 90 964 patients assessed, n=46 470 were assigned to the I-EWS group and n=44 494 to the NEWS group. Mortality within 30 days was 4·6% for the I-EWS group, and 4·3% for the NEWS group (adjusted odds ratio 1·05 [95% CI 0·99-1·12], p=0·12). In subgroup analyses I-EWS showed increased 30-day mortality for hospitals that did I-EWS in fall-winter, which was probably due to seasonality, and within patients admitted in a surgical specialty. Overall risk difference was 0·22% (95% CI -0·04 to 0·48) meaning that the non-inferiority criteria were met. The average number of scorings per patient per day was reduced from 3·14 to 3·10 (ie, a relative reduction of 0·64% [95% CI -0·16 to -1·11], p=0·0084) in the I-EWS group. INTERPRETATION: Including clinical assessment in I-EWS was feasible and overall non-inferior to the widely implemented NEWS in terms of all-cause mortality at 30 days, and the number of routine measurements was minimally reduced. However I-EWS should be used with caution in surgical patients. FUNDING: Capital Region Research Foundation, Gangsted Foundation, Candys Foundation, Herlev-Gentofte Hospital Research Foundation, Laerdal Foundation, and The Foundation of Director Boennelycke and wife.

Adjusting Early Warning Score by clinical assessment: a study protocol for a Danish cluster-randomised, multicentre study of an Individual Early Warning Score (I-EWS).

INTRODUCTION: Track and trigger systems (TTSs) based on vital signs are implemented in hospitals worldwide to identify patients with clinical deterioration. TTSs may provide prognostic information but do not actively include clinical assessment, and their impact on severe adverse events remain uncertain. The demand for prospective, multicentre studies to demonstrate the effectiveness of TTSs has grown the last decade. Individual Early Warning Score (I-EWS) is a newly developed TTS with an aggregated score based on vital signs that can be adjusted according to the clinical assessment of the patient. The objective is to compare I-EWS with the existing National Early Warning Score (NEWS) algorithm regarding clinical outcomes and use of resources. METHOD AND ANALYSIS: In a prospective, multicentre, cluster-randomised, crossover, non-inferiority study. Eight hospitals are randomised to use either NEWS in combination with the Capital Region of Denmark NEWS Override System (CROS) or implement I-EWS for 6.5 months, followed by a crossover. Based on their clinical assessment, the nursing staff can adjust the aggregated score with a maximum of -4 or +6 points. We expect to include 150 000 unique patients. The primary endpoint is all-cause mortality at 30 days. Coprimary endpoint is the average number of times per day a patient is NEWS/I-EWS-scored, and secondary outcomes are all-cause mortality at 48 hours and at 7 days as well as length of stay. ETHICS AND DISSEMINATION: The study was presented for the Regional Ethics committee who decided that no formal approval was needed according to Danish law (J.no. 1701733). The I-EWS study is a large prospective, randomised multicentre study that investigates the effect of integrating a clinical assessment performed by the nursing staff in a TTS, in a head-to-head comparison with the internationally used NEWS with the opportunity to use CROS. TRIAL REGISTRATION NUMBER: NCT03690128.

A critical assessment of early warning score records in 168,000 patients.

The national early warning score (NEWS) is recommended to detect deterioration in hospitalised patients. In 2013, a NEWS-based system was introduced in a hospital service with over 250,000 annual admissions, generating large amounts of NEWS data. The quality of such data has not been described. We critically assessed NEWS data recorded over 12 months. This observational study included NEWS records from adult inpatients hospitalized in the Capital Region of Denmark during 2014. Physiological variables and the use of supplementary oxygen (NEWS variables) were recorded. We identified implausible records and assessed the distributions of NEWS variable values. Of 2,835,331 NEWS records, 271,103 (10%) were incomplete with one or more variable missing and 0.2% of records containing implausible values. Digit preferences were identified for respiratory rate, supplementation oxygen flow, pulse rate, and systolic blood pressure. There was an accumulation of pulse rate records below 91 beats per minute. Among complete NEWS records, 64% had NEWS ≥ 1; 29% had NEWS ≥ 3; and 8% had NEWS ≥ 6. In a large set of NEWS data, 10% of the records were incomplete. In a system where data were manually entered into an electronic medical record, digit preferences and the accumulation of pulse rate records below 91 beats per minute, which is the limit for NEWS point generation, showed that staff practice influenced the recorded values. This indicates a potential limitation of transferability of research results obtained in such systems to fully automated systems.