Evidence-Based Research on Modified Early Warning Scoring (MEWS)

Much have been documented about the experiences of patients in hospital care. According to many literary works, most hospitals have failed in caring for their patients. In fact, the available literature indicate that many patients become seriously ill, experience late referrals, or even die under the watch of care professionals. Such incidences have been linked to mismanagement in health care systems in addition to delayed recognition of the medical status of the patients  (Robb & Seddon, 2010). Surprisingly, the concept of identifying patients with deteriorating health conditions has insufficiently been covered in literature. Electronic Medical Record (EMR) and Electronic Health Records (EHR) systems are gaining popularity in patient care. Among these are the track, trigger systems, and modified early warning scoring (MEWS), which are quickly gaining popularity as they can potentially be more effective than the routine nurse observations.

Research Question

Is modified early warning scoring more effective in vital sign observation as compared to clinical observations?Routine nurse surveillance has been the key mode of checking on the patients. However, scholars have questioned the effectiveness of the approach, especially in the critical care units. Alarm response systems are believed to be among the best options, which could be employed in critical care units, for early recognition, and quick responses.

Research Design of the Study

After the research approval of ethical and administrative demand (#HREC/09/QPCH/185), Prospective before-and-after intervention study was carried out to determine the vital signs frequency on observation charts of two ICU group patients. The before implementation was done in in 2009, November and the after implementation 1 month later. The sample population consisted of convenience discharged sample group discharged from the wards, and in patients with unplanned ICU admission. The before implementation sample population were composed of 69 participants, and after 70 participants (Hammond, Spooner, Barnett, Corle, Brown & Fraser, 2013).

Data Collection

Prospective information was collected from the sample population. The information included patient demographics; 24 h of recorded observations starting either from ICU discharge, or those of preceding an unplanned admission in the ICU; Acute Physiology and Chronic Health Evaluation score (APACHE II); arrest/MET call rate; ICU readmission rate; ICU and hospital length; ICU and hospital outcome, and length of stay.  

The primary outcome determined a change in all the six vital signs, or each patients sign before and following the implementation of MEWS. Vital sign variables included heart rate (HR), oxygen saturation (SaO2), temperature(T?), blood pressure (BP), urine output (UO), and  respiratory rate (RR). However, Urine Output (UO) was excluded from vital signs, due to the use of observation charge. The minimum standards were used to determine to secondary outcomes. R software package, version 2.10, was used in statistical analysis. Mean and median computations were adopted for continuous data. Other computations included Wilcoxon, t-tests, Chi-Square tests, and Fisher’s exact test (Hammond, Spooner, Barnett, Corle, Brown & Fraser, 2013).


The study was conducted in hospital in Brisbane, Australia.  The 2010 hospital statistics showed 588 beds and 35,423 admissions, annually. The hospital ICU comprised on 21 beds, admitting 1825 patients in a year. The key diagnostic demands were Gastrointestinal, Cardiovascular, and Respiratory. The study group included 24hrs post discharge and those preceding ICU admissions.  The study data were recorded before and after MEWS implementation. All patients who were above 18 years old and stayed in the ICU for over 30hrs were included in the study. In addition, all new unplanned ICU admissions were also included in the study (Hammond, Spooner, Barnett, Corle, Brown & Fraser, 2013).


  • The study was only conducted in a single hospital. A wide scale study should be conducted by including various hospitals.
  • The review period of the study was short, only 3 months. For better results, the study should be rolled in a span of at least a year, to ensure the system is integrated effectively in the hospitals.
  • The study was only conducted in the ICU, and the result cannot be effectively be used to show MEWS response in the entire hospital. A wide program of the hospital will yield better result through drawing comparisons of its scores in the units (Hammond NE., Spooner, Barnett, Corley, Brown & Fraser, 2013).
  • The integration and assessment of MEWS was not conducted to ensure efficiency in its use. For better result, the work of the system should be assessed under normal hospital operations (Hammond, Spooner, Barnett, Corle, Brown & Fraser, 2013).

Study Findings

The study reports increased frequency of vital signs following the implementation of MEWS in both the groups. Among the ICU discharged, the frequency increased by 2010%, and the result to 30% when the system was removed. Among the unplanned IUC admissions, 44% increase in frequency of vital signs was noted. There was increase in the frequency across all the vital signs. Based on the outcome, MEWS is more effective in vital sign observation as compared to clinical observations (Hammond, Spooner, Barnett, Corle, Brown & Fraser, 2013)  


Hammond, Spooner, Barnett, Corley, Brown, Fraser (2013), conducted a prospective study with the title,  The effect of implementing a modified early warning scoring (MEWS) system on the adequacy of vital sign documentation. It was conducted in a hospital in Brisbane, Australia. The goal of the research was to determine the effective of MEWS in determining vital signs among ICU patients. Despite the limitations of the study design and methodology, it illustrated that MEWS is effective in measuring vital signs (Hammond, Spooner, Barnett, Corle, Brown & Fraser, 2013). The instrument can be adopted to enhance quality care in many hospitalization areas.


MEWS is a useful tool in identifying critical patient care units. As part of hospital alarm or track and trigger system, MEWS can be used to ensure early detection, fast responses, and appropriate intervention. Based on the study, MEWS is an important track and trigger system that should be implemented in hospitals. Based on its design limitations, further researchers are recommended in this area to yield results, which are more accurate.


Cahill H., Jones A., Herkes R, Cook K., Stirling, A. & Halbert T. (2011). Introduction of a new observation chart and education programme is associated with higher rates of vital-sign ascertainment in hospital wards. BMJ Quality and Safety.20:791–6.

Hammond NE., Spooner AJ., Barnett AG., Corley A., Brown P. & Fraser JF. (2013). The effect of implementing a modified early warning scoring (MEWS) system on the adequacy of vital sign documentation. Aust Crit Care. 2013 Feb;26(1):18-22. doi: 10.1016/j.aucc.2012.05.001. Epub 2012 May 29.

Robb G, Seddon M. (2010). A multi-faceted approach to the physiologically unstable patient. Quality and Safety in Health Care.19(5):e47.