Triage systems for pre-hospital emergency medical services - a systematic review.

The emergency medical services (EMS) cover initiatives and services established to provide essential medical assistance in situations of acute illness. Triage-methods for systematic prioritizing of patients according to how urgent patients need care, including triage of requests of acute medical treatment, are adopted in hospitals as well as in the pre-hospital settings. This systematic review searched to identify available research on the effects of validated triage systems for use in the pre-hospital EMS on health outcomes, patient safety, patient satisfaction, user-friendliness, resource use, goal achievement, and the quality on the information exchange between the different settings of the EMS (for example the quality of documentation). The specific research questions were: 1) are pre-hospital triage systems effective, 2) is one triage system more effective than others, and 3) is it effective to use the same triage system in two or more settings of the EMS-chain? We conducted a systematic literature search in nine databases up to June 2012. We searched for systematic reviews (SRs), randomized controlled trials (RCTs), non-randomized controlled trials (non-RCTs), controlled before and after studies (CBAs) and interrupted time series analyses (ITSs). Two persons independently reviewed titles and abstracts, and the same persons read all possibly relevant full text articles and rated the methodological quality where relevant. The literature search identified 11011 unique references. A total of 120 publications were read in full text. None of the identified articles fulfilled our inclusion criteria, thus our question on the effects of pre-hospital triage systems, if one system is better than other systems, and the question on effects of using the same triage system in two or more settings of the EMS, remain unanswered. We conclude that there is an evidence gap regarding the effects of pre-hospital triage systems and the effects of using the same triage system in two or more settings of the EMS. The finding does not mean that pre-hospital triage systems are ineffective, but that we lack knowledge about potential effects. When introducing a new assessment tool in the EMS, it is timely to conduct well-planned studies aimed to assess the effect.