Table 1.

Evidence summary of the most commonly used triage systems

	Canadian Triage And Acuity Scale	Emergency Severity Index	Manchester Triage System
Triage system characteristics
Description	List, based on presenting signs and symptoms	Flowchart, based on physical signs and expected resource use	Multiple flowcharts, based on presentational signs and symptoms
No of levels	5	5	5
Classification and waiting time	Level I, Immediate Level II, 15 min Level III, 30 min Level IV, 60 min Level V, 2 hours	Immediate Emergent, 14 min Urgent, 60 min Semiurgent, 2 hours Non-urgent, 24 hours	Immediate Very urgent, 10 min Urgent, 60 min Standard, 2 hours Non-urgent, 4 hours
Quantity of evidence
Total no of evaluations	13	21	15
Evaluations in children	9	4	7
Evaluations in elderly	1	2	0
Diversity of evidence (range)
No of hospitals per study	1–12	1–7	1–4
Inclusions per study	481–550 940	180–37 974	872–31 622
Hospital census	10 000–75 000	10 000–90 000	7000–190 000
Hospitalisation rate	8%–47%	10%–62%	5%–33%
Risk of bias
High risk of bias in at least one domain	54%	81%	67%
High risk of bias in >1 domain	15%	23%	13%