Table 2.

Studies on validity of the ESI, CTAS, MTS in paediatric emergency care

Country	N, patients	Triage system	Design	Outcome measure	Conclusion
Canada [8]	807/560	PaedCTAS	Before and after design, prospective study	Admission rate, medical interventions, and PRISA score, comparison with previous used triage tool (4 level)	Previous triage tool had better ability to predict admission than paediatric CTAS
Canada [11]	58,529	PaedCTAS	Retrospective	Admission, ICU admission Length of stay (LOS)	Good correlation between urgency and admission, ICU admission and LOS
Canada [33]	1,618	PaedCTAS	Retrospective	Costs of resource utilization	PaedCTAS urgency level correlates well with resource utilization
USA [6]	510	ESI (version 3) Children	Prospective triage, retrospective chart review	Admission rate, medical interventions, PRISA score, comparison with used triage tool	ESI score predicts resource use, length of stay, and admission to hospital
The Netherlands [14]	1,065	MTS	Retrospective	Reference standard for urgency *	Sensitivity 63% Specificity 78%
The Netherlands [16]	17,600	MTS	Prospective	Reference standard for urgency *	Sensitivity 63% Specificity 79%

ESI = Emergency Severity Index, MTS = Manchester Triage System, PaedCTAS = Paediatric Canadian Triage and Acuity Scale

* Reference standard based on vital signs, diagnosis, resource use, admission rate, and follow-up