A systematic review on the validity and reliability of an emergency department triage scale, the Manchester Triage System

Objective: To conduct a systematic review to check the level of validity and reliability of the Manchester Triage System and the quality of reporting of literature on this topic. Design: This is a systematic review based on the PRISMA guideline on reporting systematic reviews. Data sources: The systematic search of the international literature published from 1997 through 30 November 2012 in the PubMed, Embase, Cochrane Library, Cinahl, Web of Knowledge, and Scopus databases. Review methods: This review included quantitative and qualitative research investigating the reliability and validity of the Manchester Triage System for the broad population of adults and children visiting the emergency department.After a systematic selection process, included studies were assessed on their quality by three researchers using the STARD guidelines. Results: Twelve studies were included in the review. The studies investigated the inter- and intra-rater reliability using the "kappa" statistic; the validity was tested with many measures: validity in predicting mortality, hospital admission, under- and overtriage, used resources, and length of stay in the emergency department, as well as a reference standard rating. Conclusions: In this review, the Manchester Triage System shows a wide inter-rater agreement range with a prevalence of good and very good agreement. Its safety was low because of the high rate of undertriage and the low sensitivity in predicting higher urgency levels. The high rate of overtriage could cause unnecessarily high use of resources in the emergency department. The quality of the reporting in studies of the reliability and validity of the Manchester Triage System is good.