Table 1.
Characteristics of included studies
| Study ID (first author, year) |
Country; urban/rural ED; adult/paediatric/mixed ED | Study design | Type of PHCP |
Intervention | Duration of intervention (months) | Study quality |
| Adamet al, 201445 | Saudi Arabia; urban ED; paediatric ED | RCT | Nurse | Nurse triage-plus | 0.5 | Moderate |
| Al Abri, 202046 | Oman; urban ED; adult ED | CBA | Nurse | Nurse triage-plus | NR | Low |
| Al Kadhi, 201747 | UK; NR; NR | RC study | Nurse | Nurse triage-plus | 12 | Low |
| Ashurst, 201448 | USA; urban ED; mixed ED | PC study | Nurse | Nurse triage-plus | 10 | Low |
| Celona, 201830 | USA; urban ED; adult ED | Pre–post | NP | NP Team triage | 12 | Low |
| Cheung, 200240 | Canada; urban ED; NR | RC study | Nurse | Nurse triage-plus | NR | Low |
| Day, 201331 | USA; urban ED; NR | Pre–post | NP | NP Team triage | 1 | Low |
| Demarco, 201049 | NR; urban ED; NR | PC study | Nurse | Nurse triage-plus | 1 | Low |
| Dixon, 201450 | Canada; urban ED; paediatric ED | RCT | Nurse | Nurse triage-plus | 12 | Low |
| Edwards, 201132 | Australia; urban ED; mixed ED | Pre–post | NP | NP Team triage | 17 | Low |
| Fan, 200651 | Canada; urban ED; NR | RCT | Nurse | Nurse triage-plus | 3 | Moderate |
| Fontanel, 201152 | France; NR; mixed ED | CBA | Nurse | Nurse triage-plus | 0.08 | Low |
| Gardner, 201833 | USA; urban ED; Adult ED | Pre–post | NP | NP Team triage | 0.5 | Low |
| Gaucher, 201053 | Canada; NR; paediatric ED | RC study | Nurse | Nurse triage-plus | 12 | Low |
| Hackman, 201554 | USA; urban ED; NR | RC study | Nurse | Nurse triage-plus | 17 | Low |
| Hayden, 201417 | USA; NR; mixed ED | Pre–post | NP | NP Team triage | 2 | Low |
| Ho, 201855 | China; NR; mixed ED | RCT | Nurse | Nurse triage-plus | NR | Moderate |
| Jobé, 201956 | France; NR; NR | RCT | Nurse | Nurse triage-plus | NR | Low |
| Klassen, 199357 | Canada; urban ED; paediatric ED | RCT | Nurse | Nurse triage-plus | 12 | Low |
| Kool, 200827 | Netherlands; both; NR | CBA | GP | GP team triage | 12 | Low |
| Lee, 199658 | China; urban ED; mixed ED | PC study | Nurse | Nurse triage-plus | 3 | Low |
| Lee, 201459 | Canada, urban ED; NR | RCT | Nurse | Nurse triage-plus | 12 | Moderate |
| Lee, 201641 | Canada; urban ED; adult ED | RCT | Nurse | Nurse triage-plus | 12 | Moderate |
| Li, 201860 | China; NR; paediatric ED | RC study | Nurse | Nurse triage-plus | 5 | Low |
| Lijuan, 201761 | USA; NR; NR | Pre–post | Nurse | Nurse triage-plus | 6 | Low |
| Lindley-Jones, 200042 | England; urban ED; NR | RCT | Nurse | Nurse triage-plus | 12 | Moderate |
| Love, 201225 | USA; urban ED; NR | Pre–post | NP | NP Team triage | 0.5 | Low |
| MacKenzie, 201534 | USA; NR; NR | Pre–post | NP | NP Team triage | 2 | Low |
| Parris, 199743 | Australia; urban ED; adult ED | Quasi-RCT | Nurse | Nurse triage-plus | 6 | Low |
| Pierce, 201635 | USA; urban ED; NR | CBA | NP | NP Team triage | 5.5 | Low |
| Rogers, 200436 | England; urban ED; NR | Pre–post | NP | NP Team triage | 12 | Low |
| Shrimpling, 200237 | England; urban ED; NR | Pre–post | NP | NP Team triage | 0.75 | Low |
| Sikkenga, 201662 | USA; urban ED; NR | RC study | Nurse | Nurse triage-plus | NR | Low |
| Thurston, 199644 | England; urban ED; NR | RCT | Nurse | Nurse triage-plus | 2 | Moderate |
| Tsai, 201218 | USA; urban ED; paediatric ED | Pre–post | NP | NP Team triage | NR | Low |
| Tucker, 201538 | USA; urban ED; NR | Pre–post | NP | NP Team triage | 6 | Low |
| Uthman, 201819 | England; urban ED; NR | RC study | NP | NP Team triage | 12 | Low |
| van den Bersselaar et al, 201828 | Netherlands; urban ED; NR | RC study | GP | GP team triage | 11 | Low |
| van Gils-van Rooij, 201829 | Netherlands; both; NR | CS study | GP | GP team triage | NA | Low |
| Zager, 201839 | USA; rural ED; NR | Pre–post | NP | NP Team triage | 4 | Low |
CBA, controlled before and after; CS study, cross-sectional observational study; ED, emergency department; GP, general practitioner; NA, not applicable; NP, nurse practitioner; NR, not reported; PHCP, primary healthcare provider; RC study, retrospective cohort study; RCT, randomised controlled trial.