Safety of telephone triage in out-of-hours care: A systematic review

Figures & data

Table I. Criteria for inclusion of abstracts.

Theme	Definition	Inclusion	Exclusion
Setting/population:
Out-of-hours care	Care (partly) after office hours	At least partly out-of-hours care	Only during office hours
Primary care	Care for patients with a first presentation of a medical complaint	Primary care centres, paediatrics, ambulance care, and emergency departments	Disease specific telephone lines, secondary medical care
Telephone triage	Telephone contact in which the caregiver asked questions to estimate urgency and necessary care level, in order to give advice or refer the patient	Computerised decision support systems, triage professionals, telephone triage advice, and referral services	Advice only services, computerised triage systems or websites (without a triage professional)
Outcome:
Safe performance	Triage resulting in an appropriate outcome (i.e. no under-triage, under-estimation, or under-referral)	Appropriateness, adequacy, under-triage	Appropriateness only related to efficiency
Adverse events	Triage resulting in potential harm due to inappropriate performance and/or delay	Errors/mistakes, near accidents, harm, mortality, unplanned attendance at ED, unplanned admissions within 24 hours
Other criteria:
Study design	All levels of evidence were accepted	Empirical quantitative studies, that is controlled and observational studies in clinical practice	Descriptive studies, editorials, reviews, interviews, letters, or comments
Other			Non-English, no abstract, no full text article available

Table II. Safe performance in telephone triage in observational studies (n=13 studies).

						% Safe performance (95% confidence interval)*
First author	Year	Design	Setting	Number (unselected/high risk)	Triage	Unselected patients	High-risk patients
			Emergency care
Egleston	1994	Retrospective follow-up study	ED	104	Appropriate advice in 102 of 104 cases at review; 2 calls inappropriate (=unnecessary referral to ED)	100 (96.4–100)
Srinivas	1996	Retrospective observational study	Telephone helpline and ED	300	97% of callers received appropriate advice as per protocol, while in 3% the advice given was considered to be either insufficient or inappropriate	97 (94.4–98.4)
Fatovich	1998	Prospective observational study	ED	1,682	Inappropriate advice in 1.4% of calls (=23 calls); of which 11 (48%) were assessed as potentially life-threatening and 4 (17%) as a possible risk of serious sequelae	99 (97.9–99.1)
			Ambulance care
Sramek	1994	Prospective follow-up study	Ambulance dispatch centres	398/136	132 of 136 true urgent calls were detected	99 (97.5–99.6)	97 (92.6–98.8)
Farand	1995	Retrospective observational study	Emergency Medical Services	1,006/444	18 contacts were under-triaged; 426 of 444 urgent calls were triaged accordingly	98 (97.2–98.9)	96 (93.6–97.4)
Dale	2004	Retrospective follow-up study	Ambulance services	239	For 231 calls (96.7%) the majority of the panel agreed with the non-ambulance triage decision; in 35 calls at least one member of the panel thought an ambulance was needed; secondary review showed that only 2 calls needed an emergency ambulance (0.8%) and appropriateness was 99.2%	99 (97.1–99.8)
Deakin	2006	Retrospective observational cohort study	Ambulance service call centre	263	87% of patients with a confirmed acute coronary syndrome were classified as requiring a category A response (urgent)		87 (82.4–90.5)
Fourny	2009	Prospective observational cohort study	University hospital-affiliated Emergency	245	Initial EMS dispatcher's decision was appropriate for 171 (70%) patients with ST-elevation myocardial infarction		70 (64.0–75.4)
			Medical Service call centre
			Primary care
Jackson	1997	Retrospective observational study	Primary Care Clinic and Pediatric Health Information Line	19 vs. 50	Evaluators concurred that advice was appropriate in 95% of resident calls and 98% of nurse calls	Residents: 95 (75.3–99.1)
						Nurses: 98(89.5–99.6)
Hildebrandt^1	2003	Retrospective follow-up study	Primary care physicians and answering services	119	50% (range 22–77%) of calls not forwarded to the on-call physician represented an emergency needing immediate contact with the physician	50 (41.2–58.8)
Scarfone	2004	Retrospective observational cohort study	Out-of-hours call centre of a tertiary care hospital	927/178	Compared with children referred immediately to the ED, the proportion instructed to go to the ED within 4 hours of the telephone call received significantly lower ED triage classifications (93% vs. 77%); 91.6% of non-urgent referrals were correct	98 (97.4–99.0)	92 (86.6–94.8)
St George^3	2005	Retrospective observational cohort study	Healthline	90	For 82.2% there were no safety concerns	82 (73.0–88.7)
Sprivulis^2	2004	Comparative study with concurrent controls	Health Direct and ED	842	Triage distribution at the ED of patients who complied with urgent telephone triage disposition was very similar to the triage distribution of patients triaged to non-urgent care who presented to the ED despite a non-urgent disposition (by telephone); same for hospital admissions	Not applicable
Total weighted mean				4,934/1,266		97 (96.5–97.4)	89 (86.7–90.2)

Notes: *Wilson Binominal proportion confidence interval; ¹Hildebrandt: self-triage of patients who have to decide whether or not their problem is an emergency; ²Exact figures were not available in the article; ³St George: stratified selection of contacts.

Table III. Safe performance in telephone triage in simulated patient studies (high-risk patients; n = 10 studies).

First author	Year	Setting	Number (high-risk cases)	Triage	% Safe performance (95% confidence interval)*
		Emergency care
Verdile	1989	ED	46 (1 case)	In 9% appropriate advice to go to ED by ambulance; 61% gave advice to visit ED	70 (55.6–81.3)
O”Brien	1990	Urgent care centres	100 (1 case)	In 17 of 100 calls adequate advice to consult urgent care centre or ED	17 (10.9–25.5)
Isaacman	1992	ED	61 (1 case)	60.4% advised same-day evaluation (=implicit “gold standard”); 71.7% advised to see a physician; no statistical differences between the advice of physicians vs. nurses	60 (47.9–71.7)
Evans	1993	ED	30 calls (none of 3 cases)	Correct telephone advice was given to 74% of all calls	Not applicable
Kunkler	1994	ED	72 (1 case)	In 75% appropriate advice (n=54) to go to ED by ambulance/car/taxi	75 (63.9–83.6)
Aitken	1995	ED and private ED clinics	36 (1 case)	In 20 of 36 institutions that gave telephone advice, the advice was adequate (56%)	56 (40.0–70.8)
		Primary care
Yanovski	1992	Pediatric and family medicine (private practices and hospital)	117 (1 of 3 cases)	Appropriate advice for scenario on diarrhoea and dehydration: first-year residents 52%, third-year residents 59%, private practitioners 44%, and faculty physicians 100%. More than one third of all residents and private practitioners reached inappropriate management decisions	60 (50.9–68.4)
Moriarty	2003	Primary care telephone triage system	85 (all 4 cases)	51% of calls were under-triaged (not referred)	49 (38.6–59.4)
Giesen	2007	Primary care physician cooperatives	83 (5 of 20 cases)	Correct urgency estimation by triage nurses in 69%; overestimation in 12.5%; underestimation in 19% of contacts	76 (65.8–83.9)
Derkx	2008	Primary care physician cooperatives	153 (3 of 7 cases)	Triagists achieved the appropriate triage outcome in 58% of all calls; advice was underestimated in 41% of all calls and overestimated in 1% of calls	9 (5.0–14.0)
Total weighted mean			753		46 (42.7–49.8)

Note: *Wilson Binominal proportion confidence interval.

Table IV. Overview of adverse events in telephone triage (n=13).

			Adverse events
First author	Year	Setting	Design	Mortality (after call)	Hospitalisations (after non-urgent disposition)	ED attendance (after non-urgent disposition)	Errors
Sher	1994	Telephone helpline	Follow-up study (n=317)	-	-	-	Patient status at follow-up: 3.8% worse, but no medical emergencies
Lattimer	1998	Primary care physician cooperatives	Randomised controlled trial (nurse telephone consultation vs. normal primary care physician cooperative practice) (n=7308 vs. 7184)	Within 7 days: 0.9% in control and 0.8% in nurse triage	-	-	-
Thompson	1999	Primary care physician cooperatives	Randomised controlled trial (n=100 vs. 123)	Within 7 days: no significant differences found (control vs. nurse triage)	-	-	-
Kempe (outcomes)	2003	After-hours call centre of children's hospital	Retrospective study (n=1561)	No reported deaths	4.6% urgently referred children vs. 0.45% non-urgent referred children; Weighted rate of under-referral with hospitalisation was 0.3%	-	-
Labarere	2003	After-hours primary care call centre	Follow-up study (n=409)	Death after call with non-urgent disposition: (0.2%)	-	Of patients advised to visit primary care physician during office hours, 9.6% were referred to ED subsequently	-
						Of patients with self-care advice, 32.8% went to primary care physician and 10.1% were subsequently referred to ED
St George	2005	Healthline	Retrospective observational cohort study (n=90)				In only 1.1% did the three reviewers consider that the lower endpoint posed some risk to the patient
Hildebrandt^1	2006	Private family medicine call handling	Retrospective observational study (N=119)	-	Within 2 weeks: 2% related to call	-	2% suffered clinical harm; 1% were at risk of future harm; 26% experienced discomfort
Kempe (safe)	2006	Pediatric after-hours call centre	Retrospective follow-up study (n=32,968)	No deaths within 1 week;	Potential under-referral with subsequent hospitalisation: 0.2% (calls with a non-urgent disposition)	-	-
Stewart	2006	NHS Direct and ED	Follow-up study (n=3,312)	-	21% of non-referred patients vs. 12% of NHS referred patients	-	-
Hirsh	2007	Tertiary care paediatric hospital with call centre for paediatricians	Retrospective follow-up study (n=83)	-	24-hour under-referral rate: 5.2% (hospital admission after non-urgent disposition of CC)	-	-
Killip	2007	After-hours telephone service for family medicine clinic	Retrospective observational study (n=63)	-	-	-	In total 22% of calls involved any errors that could have threatened patient safety: 14% of calls had medical errors, 11% had patient errors; 3% of calls involved errors with potentially serious consequences for the patient
Fourny	2009	University hospital-affiliated Emergency Medical Service call centre	Prospective observational cohort study (n=245)	In-hospital mortality did not differ according to the appropriateness of the initial dispatcher's decision	-	-	Inappropriate initial decision resulted in median times to reperfusion increasing by 42 minutes (patients receiving fibrinolysis) and 63 minutes (patients undergoing primary PC)
St George	2009	Nurse-on-call: telephone triage line	Retrospective observational study (N=173 189)	-	-	-	0.023% risk incidents, but no critical outcomes

Note: ¹Hildebrandt: self-triage of patients who have to decide whether or not their problem is an emergency (calls not forwarded).