Table 1.

General characteristics of the studies included in the scoping review (n = 37)

Author (year)	Country	Study design	Aims	Setting			Sample size(n)	Key findings
				PC in clinic	PC in hospital	Call center
Barnett (2009)	Australia	Descriptive	To analyze service referral and utilization patterns and examine service delivery as part of a quality improvement			√	2,571-2,892 calls annually (50–60 calls per week)	Triage nurses reported concerns about professional isolation, lack of formal education, difficulties in making decisions based on limited data as well as poor understanding of the role by users (patients and referrers).
Cariello (2003)	USA	Descriptive	To investigate service quality and cost from the perspective of callers using Computerized Telephone Nurse Triage (CTNT) for pediatric clients			√	300 Pediatric patients’ parents from 32 states, between 5pm-9pm	The caller rated the overall level of service quality highly (6.42 out of 7). The computerized telephone nurse triage saved a total of $15,183.00, or $54.42 per call.
Cox (2000)	UK	Descriptive	To compare sore throat management quality between practice nurses and GPs in a routine triage system	√			435(total) Practice nurse = 188 (consulted 44% of the patients) GPs = 247 (consulted 56% of the patients)	Outcomes like sore throat resolution, re-consultation, antibiotic use, and dissatisfaction rates were the same. Nurses saw younger patients (mean age 22.5 vs. 28.3 years) and gave more advice on home remedies (76% vs. 54%). Patients seeing the nurse had better perceptions of returning to normal health (64% vs. 53%) and quicker recovery (4 vs. 5 days).
Cynthia (2001)	USA	Case study	To identify effects of computerized telephone triage program		√		58 patients evaluated by telephone triage nurse	67%(n = 39) sent to ER appropriately, inappropriate referrals (n = 19); Evaluated by pediatrician: appropriate 89%(n = 52), inappropriate 11% (n = 6: duration of illness = 4, nature of illness = 1, other = 1)
Elliott (2020)	UK	Intervention	To examine if nurse-led triage helps manage demand for GP appointments in primary care	√			•Standard nurse-led triage = 24,060calls (2-year pilot) •Total Nurse Triage = 5,298calls (6-months pilot) •Patient satisfaction: 46 patients (female 30, male16)	Standard nurse-led triage: 13,113 GP appointments were saved by providing advice, issuing prescriptions or sick notes, or scheduling nurse appointments. Total Nurse Triage: 2,270 GP appointments were saved through referrals to dental, physiotherapy, or pharmacy services. Patient satisfaction: 93% of patients (N = 43) rated their experience as ‘excellent.’
Evans (2001)	UK	Intervention	To describe the development of a local solution for out-of-hours dental care provision in the UK			√	•Survey: 160 (GDP, dental staff) •Focus group interview: 32 (30 GDPs, 2 GP)	82% dentists considered the new system better than the existing system; 12% considered there was no difference; 6% worse than the previous system.
George (2005)	Australia	Descriptive	To describe a Peter James Centre model of triage in an aged persons mental health service			√	2,918 triage calls	Improved accessibility (increased contacts) and responsiveness. Developed the triage team: two triage officers (a psychiatric nurse and a social worker), a part-time registrar in psychiatry and consultant psychiatrist
Gibbons (2010)	UK	Descriptive	To provide guidance, entitled the Traffic Light System, to help GP and practice nurses determine the urgency of a referral.	√			-	Red: Immediate Blue: within 24 h Yellow: within one week Green: Not emergency
Giesen (2007)	Netherlands	Descriptive	To investigate whether triage nurses use national guidelines and examine the relationship between their performance and education/training.		√		118 triage nurses from 4 cooperatives	Triage nurses correctly estimated the urgency of 69% of 352 contacts and underestimated 19%. Triage nurses trained in the use of national telephone guidelines had a lower rate of underestimation of urgency. Nurses’ educational background had no significant effect on underestimation rates.
Gormley (2003)	UK	Intervention	To determine if triage by GPs or rheumatology nurses improves the positive predictive value of referrals to early arthritis clinics	√			4GPs, 2RNs, 96 patients	51% (n = 49) has inflammatory arthritis and GPs or RNs referred properly, evaluated by experienced rheumatologists. Significant stiffness in the morning or after rest and objective joint swelling were the most important clinical features.
Harmsen (2005)	Netherlands	Descriptive	To determine the actions of triage nurses at GP co-operatives when a child is suspected of having a UTI or presents with a fever	√			145 triage nurses	For suspected UTI, all triage nurses requested a urine sample, but only 70% gave instructions on how to collect the urine. There is a potential for over-diagnosis of UTIs, as nurses often request GP visits for children with fever without a clear focus, even when UTI is not their primary suspicion.
Hathorn (2009)	UK	Descriptive	To establish the safety and effectiveness of nurse-led triage of otolaryngology out-patient referrals		√		2 consultants 2 specialist registrars 2 senior house officers 2 otolaryngology nurse (1 triage-grained) 100 referrals reviewed	Urgent 7%; soon 26%; routine 67% Showing good agreement with a senior ENT consultant on outpatient referrals. No cases were triaged inappropriately, and no urgent cases were missed.
Huibers (2012)	Netherland	Descriptive	To explore the impact of quality of consultation and estimated urgency on the appropriateness of decisions.	√			6,739 nurse telephone contacts of 623 triage nurses from 25 GPCs across the Netherlands	Significant correlation between quality of consultation and appropriateness of decision concerning urgency, follow-up advice and timing. An increase in urgency seemed to be related to a decrease of appropriate decisions for urgency estimations and an increase for follow-up advice and timing.
Kempe (2006)	USA	Descriptive	To assess compliance with nurse recommendations, death rates, and factors linked to under-referral in children triaged by a pediatric after-hours call center			√	32,968 calls from pediatric patients’ parents	21% received urgent (n = 7,039), 27% next-day (n = 8,862), 4% later visit (n = 1,360), and 48% home care recommendations (n = 15,707). The potential under-referral rate leading to hospitalization was 0.2% (1 per 599 triaged calls). Higher under-referral risk was linked to age (6 weeks or 12 years) and calls after 11 PM. Urgent and home care compliance rates were 74%, while next-day compliance was 44%. No deaths occurred within a week of after-hours calls.
Leydon (2013)	UK	Descriptive	To identify the process of delivering and seeking cancer related telephone help			√	52 (cancer patients, family, friends, and carers)	Four elements of the triaging process: Recognition, Self-identification, Formulation of the reason for calling, Request for further telling
Light (2005)	USA	Descriptive	To identify if parental advice from telephone triage nurses changed care location from the ED or doctor’s office to home			√	110 calls from pediatrics’ parents	Most parents in this study (n = 74) who called the Children’s Careline wanted their child seen either in the ED (n = 7) or in the physician’s office (n = 67). After triage, 21 parents sought formal care for their child. Thus, 53 parents performed home care for their febrile child as counseled by triage nurses. Most parents did follow home-care advice.
Magann (2022)	USA	Descriptive	To determine the agreement between advice given to obstetric patients by a call center and healthcare providers with varying experience			√	91 pregnant women	The call center nurses advised emergency care more frequently (51.7%) than the MFM (44%) and the APN (31.9%) but less frequently than the OB-GYN resident (57.1%). Advice given by nurses at an obstetric call center was highly consistent with the most skilled specialist (MFM) followed closely by OB-GYN resident or an APN.
Majeed (2023)	Qatar	Intervention	To improve categorization and identify training effectiveness.			√	470 medical records of patients from 26 health centers	After triage training, nurses improved their accuracy (63% →90%), correctly categorizing medical emergencies. Reducing over-triage 37% →10% The 5-minute physician response target in emergencies also improved from 48–55%.
Marklund (2007)	Sweden	Descriptive	To evaluate a telephone nurse triage model regarding referral appropriateness, patient compliance, and costs			√	362 Patients	Out of 362 patients, advice was adequate in 97.6% of cases. Compliance rates were 81.3% for self-care, 91.1% for primary health care, and 100% for A&E. Nurses improved care adequacy for 64.7% of self-care and 29.6% of A&E referrals. Cost savings per call were €70.3 for self-care, €24.3 for primary care, and €22.2 for A&E.
Marvicsin (2015)	USA	Descriptive	To identify the role and cost savings of an after-hour call system in averting ED visits			√	124 Health center callers	50% of the 124 calls averted an ED visit, saving an estimated $19,406. Another 43% of the calls were for non-urgent concerns and only 9(7%) calls resulted in an ED referral.
McGra (2000)	USA	Intervention	To identify if this process of triaging and self-care education was effective	√			35,231 patients	Central triage has demonstrated an annual cost avoidance exceeding 2,500,000$
McGrath (2008)	UK	Descriptive	To improve the quality and safety of telephone triage in after-hours services through a quality framework		√		-	The quality framework consists of three key components: training, protocols, and documentation. The service reduced the need for GP contact by over 50%, improved GP recruitment and retention, and was well-received by both GPs and consumers.
Moll van Charante (2006)	Netherlands	Descriptive	To explore determinants related to nurse telephone advice alone (NTAA)		√		GP 25, Nurse 8	Out of 1,421 calls, 1,030 (72.5%) were referred to a GP, while 391 (27.5%) received NTAA. The return consultation rate was 26.9% for GP referrals and 33.8% for NTAA. Nurses felt confident providing NTAA to younger patients with symptoms like earache, vomiting, or cough, but were more cautious with those showing multiple or serious symptoms, such as chest pain or abdominal pain. NTAA was more common at night than during the day or evening.
Navratil-Strawn (2014)	USA	Descriptive	To estimate the relationship between adherence to nurse recommendations and healthcare expenditures for callers to a Nurse HealthLine triage program			√	53,206 Nurse HealthLine triage calls	Total 53,206 calls, 29,438 adherent(55%), 23,768non-adherent(45%). Nurses were over three times more likely to recommend higher-level care, such as the emergency room, for those needing it. This guidance resulted in significant annual savings of $13.8 million, primarily benefiting Medicare, and yielded a positive return on investment of $1.59.
O’Cathain (2007)	Scotland	Descriptive	To assess nurse attitudes toward risk in telephone assessments using CDSS and their impact on decision-making			√	211 nurses	The response rate was 57% (265/464). Analysis of 231,112 calls matched to 211 nurses revealed that 16% (36,342 calls) were directed to self-care. Nurses in the top 10% recommended self-care three times more often than those in the bottom 10%. Community nurses were less likely to suggest self-care than those from acute settings. Much of the decision-making variation remained unexplained, and nurses’ risk attitudes did not significantly influence their choices, likely due to measurement limitations.
Richards (2000)	UK	Descriptive	To describe the changes required to introduce a nurse telephone triage system into a large primary care practice	√			-	Addressing workload and access issues in primary care requires a whole-systems approach. Key to success was empowering the nursing team through leadership, skills mix review, innovative resource use, team building, and collaboration among nurses, doctors, and reception staff. Time has been crucial in implementing these changes, and policymakers should recognize this in the evolving primary care landscape.
Richards (2002)	UK	Intervention	To compare GP and nurse workloads and costs of patient care for nurse telephone triage vs. standard same-day appointment	√			4,685 patient total (1,233 standard management & 3,452 the triage system)	Triage reduced the number of same day appointments with GPs but resulted in busier routine surgeries, increased nursing time, but significant increase in out of hours and accident and emergency attendance. Consequently, triage does not reduce overall costs per patient for managing same day appointments.
Richards (2004a)	UK	Randomized Controlled Trial	To determine if off-site triage by a nurse is a feasible option for primary care (workload and cost)	√			4,703 patients total (2,452 practice based triage & 2,251 NHS direct triage)	Patients in the NHS Direct group were less likely to have their call resolved by a nurse and more likely to see a GP. Their mean total time per patient was 7.62 min longer than the practice-based group. Costs were higher in the NHS Direct group by £2.88 per patient due to differences in patient contact points after triage.
Richards (2004b)	UK	Descriptive	To assess the impact of nurse telephone triage in primary care on the consulting behaviors of GPs		√		2,182 consultations (IG 1,102 & CG 1,080)	Patients in the triage system presented more health issues and received more consultations, prescriptions, and investigations, while referral rates to secondary care remained unchanged.
Scalvini (2005)	Italy	Intervention	To analyze a home-based telecardiology intervention in congestive heart failure patients, focusing on the role of nurse triage and one-lead ECG monitoring	√			3,767 calls from 230 patients with chronic health failure	In 2,417 of 3,767 calls, nurses took no action. In 418 calls, they recommended therapy changes, admitted 62 patients, arranged investigations for 243, and consulted GPs for 41. Nurses conducted 2,303 one-lead ECGs, identifying issues in 6% of cases, leading to beta-blocker adjustments for 79 patients.
Trip (2021)	Scotland	Descriptive	To describe the use and impact of the national cancer helpline			√	8,385 calls from 6,562 patients	Helpline use rose by 83.6% from 2016 to 2020, mainly due to increased in-hours calls. Of the calls, 41% needed professional review only, 24% required review and admission, and 35% received telephone advice only.
Eldh (2020)	Sweden	Qualitative	To describe healthcare staff’s experience with a digital communication system for patient encounters in primary care	√			21 health care staff at 5 primary care center	Patient-uploaded photos on the digital system provided supplementary data, enabling safer assessments and better agreement among the healthcare team during triage.
Goransson (2020)	Sweden	Qualitative	To describe nurses’ experiences of triaging patients at walk-in clinics at primary healthcare centers	√			12 RN from five different health centers	In-person interactions enabled nurses to use eye contact and physical exams for better assessments. Their expertise increased confidence, while collaboration with colleagues provided support when needed.
Holmström (2007)	Sweden	Qualitative	To explore user perspectives on decision aid software for telenursing			√	12 nurses	The decision aid software assists with assessment but lacks support for decision-making. Users noted inconsistencies between the software and actual practice, limited learning resources, and communication challenges with the software.
Rosen (2000)	UK	Qualitative	To examine the role of inter-professional collaboration in the development of NHS Direct, the new national telephone triage service			√	29 (Representatives of NHS Direct, local GPs, accident and emergency consultants, representatives of relevant health authorities, community trusts, community health councils)	The role of triage nurses in NHS Direct involved working independently of doctors, guided by computerized triage systems to assess patients, while doctors provided support for more complex cases.
Reblora (2021)	Singapore	Mixed method (observation + in-depth interview)	To explore the experiences of nurses working in triage stations of primary health care centers	√			22 RN	The 19 participants valued their nursing experience, which helped them recognize common diseases and make initial assessments. Patient frustration due to long waiting times, particularly among younger patients who had high expectations influenced by instant access to information via mobile devices. Teamwork with physicians was essential, but some nurses felt that electronic communication was inadequate for triage, expressing a preference for face-to-face discussions to convey their assessments more effectively.

Note. A&E = Accident & Emergency; APN = Advanced Practice Nurse; CDSS = Clinical Decision Support System; ED = Emergency Department; ENT = Ear, Nose, and Throat; ER = Emergency Room; GDP = General Dental Practitioner; GPs = General Practitioners; MFM = Maternal-Fetal Medicine; OB-GYN = Obstetrics and Gynecology; RN = Registered Nurse; UTI = Urinary Tract Infection