(2022) 22:146
Vuorinen et al. BMC Emergency Medicine
https://doi.org/10.1186/s12873-022-00706-5

Open Access

RESEARCH

Cortical symptoms described in emergency
calls for patients with suspected large vessel
occlusion: a descriptive analysis of 157
emergency calls
Pauli Vuorinen1,2*, Joonas Kiili1,2, Essi Alanko1,2, Heini Huhtala3, Jyrki Ollikainen4, Piritta Setälä2 and
Sanna Hoppu2

Abstract
Background: Emergency medical dispatchers typically use the dispatch code for suspected stroke when the caller
brings up one or more symptoms from the face-arm-speech triad. Paramedics and emergency department physicians
are trained to suspect large vessel occlusion stroke when the stroke patient presents with hemiparesis and cortical
symptoms: neglect, aphasia, and conjugate eye deviation (CED). We hypothesized that these symptoms could be
evident in the emergency call.
In this study, we aimed to describe common symptoms mentioned in the emergency calls for paramedic-suspected
thrombectomy candidates. Secondly, we wanted to explore how the question about CED arises in the Finnish suspected stroke dispatch protocol. Our third aim was to find out if the symptoms brought up in suspected stroke and
non-stroke dispatches differed from each other.
Methods: This was a retrospective study with a descriptive analysis of emergency calls for patients with paramedicsuspected large vessel occlusion stroke. We listened to the emergency calls for 157 patients transported to Tampere
University Hospital, a Finnish comprehensive stroke centre. Two researchers listened for symptoms brought up in
these calls and filled out a pre-planned case report form.
Results: Speech disturbance was the most common symptom brought up in 125 (80%) calls. This was typically
described as an inability to speak any words (n = 65, 52% of calls with speech disturbance). Other common symptoms
were falling down (n = 63, 40%) and facial asymmetry (n = 41, 26%). Suspicion of stroke was mentioned by 44 (28%)
callers. When the caller mentioned unconsciousness the emergency dispatcher tended to use a non-stroke dispatch
code. The dispatchers adhered poorly to the protocol and asked about CED in only 57% of suspected stroke dispatches. We found CED in 12 emergency calls and ten of these patients were diagnosed with large vessel occlusion.
Conclusion: In cases where paramedics suspected large vessel occlusion stroke, typical stroke symptoms were
described during the emergency call. Speech disturbance was typically described as inability to say anything. It

*Correspondence: pauli.e.vuorinen@pshp.fi
2
Department of Emergency, Emergency Medical Services, Centre
for Prehospital Emergency Care, Anaesthesia and Pain Medicine, Tampere
University Hospital, PO Box 2000, FI‑33521 Tampere, Finland
Full list of author information is available at the end of the article

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Page 2 of 9

is possible to further develop suspected stroke dispatch protocols to recognize thrombectomy candidates from
ischemic cortical signs such as global aphasia and CED.
Keywords: Emergency medical dispatch, Emergency medical services, Large vessel occlusion stroke

Background
Ischemic stroke causes an enormous burden when disability, mortality and financial aspects are considered
[1]. A great deal of this burden is caused by large vessel
occlusion (LVO) stroke [2]. The middle cerebral artery
(MCA) nourishes most of the brain volume and surface
area. Occlusion of its first segment, the M1-branch, is the
most common target of endovascular treatment [3].
International treatment guidelines recommend that
emergency medical services (EMS) develop methods to
suspect LVO in patients with severe stroke symptoms
[4, 5]. For this purpose, prehospital LVO scales have
been formulated, but few have been tested in real life [6].
These LVO scales rely on the existence of cortical symptoms: conjugate eye deviation (CED), spatial neglect,
and aphasia occurring alongside motor hemiparesis [7].
Among these cortical symptoms, CED has been shown
to associate with large infarcts [8]. An exception to other
prehospital LVO scales is the Stockholm Stroke Triage
System in which the suspicion of LVO is solely based on
the severity of motor hemiparesis [9]. In very recently
published results from the RACECAT trial [10], Pérez de
la Ossa et al. showed that the time from onset to groin
puncture in patients with LVO significantly decreased
when the EMS bypassed the primary stroke centre (PSC).
Timely recognition of stroke in the prehospital setting
will accelerate time-critical interventions at in-hospital
care [11–13]. The clinical management of stroke and
accuracy of the dispatch criteria are among the most
urgent research topics in prehospital care [14, 15]. CED
and neglect were first included in the validation of a
suspected stroke dispatch protocol by Krebes et al. [16].
Regrettably, the authors indexed patients only as having
ischemic strokes or transient ischemic attacks and did
not provide the number of LVOs. The PLUMBER Study
[17] reported the prevalence of LVO in a population of
dispatcher- and paramedic-suspected strokes. No publications describe the content of emergency calls of LVO
patients, nor are there trials aiming to improve LVO recognition during the emergency call.
Our hypothesis was that aphasia and CED, at least,
could be evident during the emergency call and if probed
by the dispatcher would facilitate early detection of LVO.
This could drastically change the EMS strategy by making it possible to activate a mobile stroke unit [18] or a
helicopter [19] early in the triage and transport an LVO
stroke patient directly to the comprehensive stroke centre

(CSC). Unfortunately, in our previous publication [20],
we concluded that the answer the dispatchers marked in
the dispatch database to the CED question: ‘is the face or
the gaze of the patient away from the side of the hemiparesis?’ did not recognize patients with LVO.
In this study, we describe common symptoms mentioned in emergency calls concerning patients with a
paramedic-suspected LVO and primarily transported to
our university hospital serving as a comprehensive stroke
centre for one million people. In addition, we aim to
determine why the dispatcher’s detailed question about
CED is ineffective in recognizing LVO. Since the dispatcher asks the CED question only in suspected stroke
dispatches, our third aim was to find out if the symptoms brought up in suspected stroke and non-stroke dispatches differed from each other.

Methods
Study design

This is a retrospective and descriptive analysis of emergency calls for patients with paramedic-suspected LVO.
Setting
University hospital and emergency medical services

The emergency department of Tampere University Hospital serves as a CSC for a population totalling one million. The EMS transports all suspected stroke patients
primarily to Tampere University Hospital from the Pirkanmaa Hospital District (Fig. 1). The EMS personnel
from the imminent frontier of neighbouring hospital districts are trained to screen possible LVO strokes using the
Finnish Prehospital Stroke Scale (FPSS) [21]. It is an easily memorized and binary categorized five-item screen
for stroke patients. The first four items look for deficits in
face, arm, leg and visual field. An abnormal finding in any
of these items makes the patient a candidate for intravascular thrombolysis. The fifth item in FPSS is partial
or forced CED in the opposite direction from any limb
weakness. Paramedics consider a patient presenting with
CED and any of the first four items as a candidate for
mechanical thrombectomy. They consult the 24/7 on-call
neurologist at the CSC to determine whether the patient
should be diverted from the PSC and transported straight
to the CSC, i.e., the mothership strategy [22]. Otherwise,
patients from the five closest PSCs are transported to the
CSC only after their eligibility for mechanical thrombectomy has been confirmed and intravenous thrombolysis

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Fig. 1 Map of the study area with a strengthened black line encircling Pirkanmaa hospital district, a square pattern indicating the hospital districts
with primary stroke centres referring patients to Tampere University Hospital and solid grey areas representing the municipalities from which
patients with suspected large vessel occlusion are transported straight to Tampere University Hospital

potentially started in PSC, i.e., the drip-and-ship strategy
[22]. A special thrombectomy alert is generated after the
paramedic’s telephone consultation with the neurologist at the CSC. This alert is relayed to the personnel of
the emergency department, those performing the computed tomography of the head, the neuro-interventional
radiologist, the angio suite, the anaesthesia team and
the high-dependency stroke unit. Our standard operating procedure states that primary targets for mechanical thrombectomy are the internal carotid artery, first
and second branches of the middle cerebral artery, first
branches of anterior and posterior cerebral arteries, and
basilar artery. When anatomical conditions are suitable,
also more peripheral parts of intracranial arteries may be
considered. There were 178 mechanical thrombectomies
done at Tampere University Hospital in 2020.
Emergency medical communication centre

All emergency calls in mainland Finland are operated by
the Emergency Response Centre Agency Finland, which
handles three million emergency calls per year. There are
445 dispatchers taking emergency calls in Finland. During 2018–19, the emergency call process was renewed.
The computer-based Emergency Response Integrated
Common Authorities (ERICA) was introduced to unite
the dispatch system of all authorities: police, EMS, rescue services, emergency social welfare services and

border guard. At the same time, the handling process of
suspected strokes was revised. It resembles closely the
Medical Priority Dispatch System card #28 [23]. According to the protocol, a suspected stroke is now dispatched
to the EMS if the caller brings up the idea of a stroke or
if one or more symptoms of the face-arm-speech triad
are mentioned. At the time of data acquisition, the EMS
responded immediately to suspected stroke dispatches
with lights and sirens if the time from the last known
point at which the individual was well was less than 6 h
or if the patient woke up with stroke symptoms. Finally,
and as a deviation from the card #28, ERICA guides the
dispatcher to screen for a possible LVO by asking if the
patient’s head or gaze tends to turn away from the side
of the hemiparesis. The dispatcher has three options
to mark as the answer to this question in the ERICA
report: yes, no and unknown. It is not mandatory to ask
the question, meaning the dispatcher may leave it unanswered. A positive answer to this question generates a
separate notification to the EMS field commander. After
the stroke dispatch, the emergency dispatcher tells the
caller to make sure that the patient is at rest and that the
scene is accessible.
Study population

The study population consisted of emergency calls
for patients with paramedic-verified CED and their

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prehospital prenotification generating a thrombectomy
alert at the receiving hospital.
Data collection

We went through the electronic patient records of all
consecutive thrombectomy alerts at Tampere University Hospital emergency department after the deployment of ERICA (13th February 2019) until 31st August
2020 and reviewed the neurologist’s notes, the emergency department diagnoses and the radiologist’s
report of the computed tomography angiography. We
included EMS callouts coupled with these thrombectomy alerts where we could verify from the patient
records that the paramedics confirmed CED during
the EMS callout. We excluded patients who came from
a PSC with a confirmed LVO and patients admitted to
the emergency department from the wards of our own
institution. The emergency call recordings and ERICA
reports from these EMS callouts were requested from
the Emergency Response Centre Agency Finland based
on the date and time of the emergency call and the
dispatch code generated from the call. The recordings
were listened to, and a pre-planned case report form
(Supplementary file) was filled out independently by
two of the authors (P.V. and E.A.). P.V. is a specialist
in anaesthesia and intensive care medicine. He has a
subspecialty in prehospital medicine. E.A. is a secondyear medical student. She has no previous contact with
emergency medical services or the emergency response
system. These results were then compared, and in case
of disagreement, P.S. and S.H. were consulted to come
to a consensus.

Page 4 of 9

Ethics

The Ethics Committee of Tampere University Hospital
supported the study design (ETL R20082R), and approval
to view the patient records was granted by the hospital’s research director. The Emergency Response Centre Agency Finland granted a separate authorisation to
access the emergency call recordings (HAK-21142). No
interventions were performed and none of the patients
were contacted in the study. Hence, the Ethics Committee of Tampere University Hospital waived the need for
informed consent of the patients.

Results
Patients

During the study period, the neurologists working in the
emergency department treated 5025 patients altogether,
and among these patients, there were 399 patients with a
thrombectomy alert. Of these cases, 157 had both a paramedic-verified CED and connected emergency calls. The
patient flow is presented in Fig. 2.
Table 1 contains information about the patient demographics, dispatch details and emergency department
diagnoses. The median age of the patients was 76 years
­(Q1–Q3: 69.5–83.1 years) and 85 (54%) of them were
male. Most patients (n = 134, 85%) had a pre-existing
condition diagnosed before the incident leading to the
emergency call. The most common diagnosis made at
the emergency department was acute ischemic stroke
(n = 116, 74%), of which 95 had LVO (61% of all patients,
82% of ischemic strokes). Mechanical thrombectomy was
performed on 79 patients (50% of all patients, 68% of
ischemic strokes).
Dispatch information

Statistics

Categorical and continuous variables were analysed, and
the results were used to identify differences between the
suspected stroke and non-stroke dispatch groups. Categorical variables were analysed using cross-tabulation,
and the χ2 test or Fisher’s exact test were carried out as
appropriate. Continuous variables were analysed using
the Mann-Whitney U-test. For the most common symptoms, 95% confidence intervals were calculated. Hypothesis testing was two-sided, and a p-value of ≤0.05 was
considered statistically significant. Binary logistic regression modelling with forward stepwise selection (probability for entry ≤0.05, probability for removal ≥0.10) was
used to aim to find out what symptoms are commonly
brought up in the suspected stroke dispatches. IBM SPSS
Statistics, version 27 (IBM Corp., Armonk, NY, USA) and
Stata 16.0 (StataCorp, College Station, TX, USA) were
used for statistical analyses.

The dispatchers suspected stroke in 88 (56%) of the emergency calls. Of non-stroke dispatches (n = 69, 44%), the
most common codes were unconscious (n = 20, 29%), fall
(n = 15, 22%), and cardiac arrest (n = 7, 10%). Regardless
of the EMS callout dispatch code, the dispatch urgency
was an immediate response with lights and sirens in 140
(90%) cases.
The onset time of symptoms was unknown to the caller
in 71 (45%) calls. In those cases, the dispatcher decided
to use a non-stroke dispatch code (n = 40) more often
than a suspected stroke dispatch code (n = 31; p = 0.004).
Symptoms described in the emergency calls

In 44 (28%) emergency calls, the caller mentioned suspecting a stroke as the cause of the bout of illness. The
most common symptoms during the emergency calls
are presented in Fig. 3. In logistic regression modelling,
the dispatcher preferred the dispatch code for suspected

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Fig. 2 Patient flow. EMS, emergency medical services; CED, conjugate eye deviation; LVO, large vessel occlusion; PSC, primary stroke centre

stroke over a non-stroke dispatch code when facial asymmetry (OR 30.0, 95% CI 4.9–185.0), upper (OR 13.7, 95%
CI 2.3–81.6) or lower (OR 7.1, 95% CI 1.3–39.5) extremity weakness, or speech disturbances (OR 4.7, 95% CI
1.5–14.8) were mentioned. When unconsciousness came
up in the emergency call, the dispatcher tended not to
use the suspected stroke dispatch code (OR 0.05, 95% CI
0.006–0.47).

person”. The OR for using the dispatch code for “unconscious person” instead of suspected stroke code when the
caller described that the patient is unable to speak anything was 38 (95% CI 4.9–290). Other examples of the
description of speech disturbance were “unclear speech”,
“incomprehensive” and “slurring”.

Speech disturbance

The callers typically described motor symptoms with
phrases like “the face of the patient is asymmetric”, “the
other side is not working”, “the patient has lost strength
in the right/left arm” and “the patient is unable to stand
up”. In eight (5%) emergency calls, the dispatcher succeeded in guiding the caller to test the strength of the
patient’s upper extremities and discovered the side of the
hemiparesis correctly over the phone.

Speech disturbance was by far the most common identifying symptom described in the emergency calls analysed. It was either spontaneously mentioned or inquired
after by the dispatcher in 125 (80%) calls. Inability to
form any words was mentioned 65 (41%) times in total.
This was the case in 19 of the 20 (95%) cases when the
dispatcher chose the dispatch code for “unconscious

Motor symptoms

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Table 1 Patient and emergency call characteristics
Suspected stroke dispatch n = 88

Non-stroke dispatch n = 69

n/median

% /(Q1–Q3)

n/median

% /(Q1–Q3)

P-value

Male

47

53.4

37

53.6

0.979

Age, years

74.3

(67.2–82.7)

78.8

(70.7–83.7)

0.135

previously healthy

18

20.5

5

7.2

0.020

hypertension

57

64.8

53

76.8

0.102

atrial fibrillation

29

33.0

31

44.9

0.125

anticoagulation

24

27.3

18

26.1

0.868

diabetes

20

22.7

15

21.7

0.883

coronary disease

15

17.0

14

20.3

0.603

dementia

6

8.0

10

14.4

0.115

spouse

38

43.2

19

27.5

outsider

24

27.3

21

30.4

close relative

17

19.3

15

21.7

healthcare professional

7

8.0

14

20.3

indefinite

2

2.3

0

private residence

68

77.3

46

66.7

public place

15

17.0

11

15.9

healthcare facility

5

5.7

12

17.4

LVO stroke

53

60.2

42

60.9

non-LVO stroke

15

17.0

6

8.7

intracerebral haemorrhage

20

22.7

14

20.3

seizure

0

7

10.1

Medical history

Caller

0.061

Destination of EMS callout

0.063

Diagnosis

0.009

EMS Emergency medical services, LVO Large vessel occlusion

Fig. 3 Proportion (with 95% confidence interval) most common symptoms mentioned in the emergency calls

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Conjugate eye deviation

CED was asked about in 50 emergency calls (57% of the
n = 88 suspected stroke dispatches), and the question was
directed correctly 13 times, i.e., inquiring after the direction of the forced gaze. The callers mentioned CED in 12
(8%) of the n = 157 emergency calls analysed. In these
12 cases the dispatcher twice marked “no” in the ERICA
report and twice left the question unanswered. Of the 12
patients with a positive CED answer, 11 were diagnosed
with an ischemic stroke and of these 10 had LVO in computed tomography angiography.
Typical phrases in incorrectly placed CED questions
were “is the patient forced to look in either direction?”, “is
the patient able to look at you?” or “do see anything peculiar in the gaze of the patient?”

Discussion
Our findings indicate that callers describe paramedicsuspected thrombectomy candidates as having typical
stroke-associated symptoms, but dispatchers also use
dispatch codes like “an unconscious person”, “a fallen person” or “cardiac arrest”. Among stroke symptoms, severity of speech disturbance, described as an inability to
speak any words, could be a reasonable marker for LVO
in emergency calls, but the dispatchers need further education since these patients were easily miscoded as being
unconscious. In addition, caller-verified CED is valuable
information that should be relayed to the EMS.
The emergency dispatcher’s sensitivity to recognize
stroke ranges from 35% [24] to 80% and over [25, 26].
In Finland, Mattila et al. [27] recorded a sensitivity of
72% before ERICA was implemented. Yet, the level of
the emergency dispatcher’s sensitivity is connected with
the false positive rate, i.e., when one increases, so does
the other. The positive predictive value of stroke in suspected stroke dispatches can fall as low as 20% [26]. In
our study, the dispatchers had a 59% sensitivity in recognizing and using correctly the suspected stroke dispatch
code for patients later diagnosed with ischemic stroke in
the ED. Often, we found that inability to speak any words
instead directed the dispatcher towards the “unconscious
person” code. Interestingly, Mattila et al. [27] mention
the caller describing speech disturbance as “He is not
talking at all” in non-stroke dispatches but they fail to
report the percentage of emergency calls with this feature. They also found that a fall at the onset of stroke was
a predictor of the dispatcher using a non-stroke dispatch
code. This is not consistent with our study. We found
that the dispatcher used the code for suspected stroke,
even though the caller mentioned the patient had fallen
down. We have to keep in mind that these study samples
are different. Mattila et al. [27] studied emergency calls
for patients with diagnosed stroke or transient ischemic

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attack but we studied emergency calls for patients with
paramedic-suspected LVO.
In almost all cases in our study, the dispatcher recognized the need for a high urgency dispatch. This was
more notable than in an earlier study concerning Finnish
stroke dispatch [27], possibly because the patients presented with more severe symptoms than in earlier studies. High urgency and immediate response are crucial
factors in the successful treatment and management of
stroke patients, though the dispatch code that is used is
not inconsequential either. Paramedics act faster on the
scene and adhere to neurological protocols better when
dispatched with a suspected stroke code [11, 12]. These
lead to better prehospital stroke recognition which hastens the patient’s in-hospital care [13].
We found that there is the potential to identify CED
during the emergency call, but that dispatchers’ adherence to the protocol was disappointing. In the calls we
studied, the CED question was either not asked or was
asked but in a way that failed to elucidate the direction
of the possible forced gaze. In our previous study [20]
we did not have access to the emergency call recordings.
We concluded in that study that the ERICA reports show
that in 17% of suspected stroke dispatches the CED question is unanswered. In this present study, we found that
the true percentage of unasked CED questions was 43%.
Further to this, the fact that dispatchers mismarked a
positive answer for CED in the ERICA report shows a
lack of proper implementation of the protocol. We also
must keep in mind that inquiring about CED is instructed
only in cases of suspected stroke, but a little less than half
(41%) of the patients diagnosed with ischemic stroke
in the ED were dispatched with a non-stroke dispatch
code, meaning that the CED question never came up in
ERICA during these calls. Going forwards, it is essential to decrease this portion of false-negative dispatch
codes in stroke patients. We discovered three features
in the emergency calls which typically led the dispatcher
to choose a non-stroke dispatch: patients found with
stroke symptoms after an unknown time from the onset
of stroke, and emergency calls in which the caller mentioned that the patient was unconscious or unable to
speak at all. These have to be taken into account when
planning further education for the dispatchers.
In this research, we were delighted to note that eight
dispatchers prompted the caller to find out whether the
patient has motor symptoms. In each case, they correctly figured out the hemiparetic side. Previously, Mazya
et al. [9] introduced a prehospital LVO scale based on the
severity of the motor hemiparesis, as estimated during a
teleconsultation. In their study, an ambulance nurse consulted the stroke physician at the CSC when they met a
patient with a positive face-arm-speech -test. The stroke

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physician then assessed the severity of the hemiparesis
on a scale from 0 to 2 for both, ipsilateral arm and leg.
They reported a positive predictive value of 41% for this
method to recognize LVO in cases in which the stroke
physician considered the hemiparesis to be severe. This
suggests that with proper education and dispatch protocol modifications, it could be possible to reliably deduce
the side of the hemiparesis during the emergency call and
whether the gaze of the stroke patient is directed away
from this side. This could improve the possibility to discover LVO patients earlier and transport them directly to
CSC.
Strengths and limitations

Our second aim of this study was to find out why the
CED question did not recognize LVO patients in our
previous study [20]. Therefore, we deliberately chose to
listen to emergency calls in which we could easily demonstrate that the paramedics had recognized the patient
as a thrombectomy candidate on the grounds of CED.
As such, we acquired 157 emergency call recordings
out of 399 thrombectomy alerts. There is a possibility
that larger-scale sampling could have produced a more
accurate analysis. Yet, this work should be considered
as a pilot study encouraging emergency dispatch centres review their protocols to include questions around
CED and global aphasia in suspected stroke dispatch
protocols.
Further to this, we did not look for neglect in the emergency calls since the dispatcher did not ask about it and
we thought it would be difficult to recognize from the
spontaneous narration of the caller. Yet, Zhao et al. [28]
developed an algorithm for paramedics to use to spot
neglect with a shoulder tap test if the patient’s left arm is
weak. There are no reasons why this could not be incorporated into the dispatcher’s suspected stroke algorithm.
A further limitation of this study is that we present no
comparison to other neurological emergencies. To overcome this limiting factor, we recommend that future
studies compare emergency calls for LVO patients with
those for patients with distal occlusion strokes.
Nonetheless, the strength of this study is that—excluding one emergency call—all the callers were native
Finnish speakers, and the quality of the recording was
considered good or acceptable in each case.

Conclusion
This is the first study to describe emergency calls for
paramedic-suspected LVOs. We have demonstrated that
paramedic-suspected thrombectomy candidates present with typical stroke symptoms in emergency calls.
Cortical symptoms, most commonly speech disturbance
described as an inability to speak any words, and to a

Page 8 of 9

lesser extent CED, are also evident. This demonstrates
the potential for developing the dispatch protocols for a
suspected stroke to recognize LVO in an emergency call.
Appropriate training and simple instructions included in
the stroke dispatch protocol could improve dispatchers’
accuracy. The dispatcher could, for example, encourage
the caller to test if a patient, who is unable to say anything, presents with motor hemiparesis and thereafter
enquire about CED. LVO identification at a very early
stage would revolutionize the stroke triage.
Abbreviations
CED: Conjugate eye deviation; CSC: Comprehensive stroke centre; EMS: Emergency medical services; ERICA: Emergency Response Integrated Common
Authorities; FPSS: Finnish Prehospital Stroke Scale; LVO: Large vessel occlusion;
MCA: Middle cerebral artery; PSC: Primary stroke centre.

Supplementary Information
The online version contains supplementary material available at https://​doi.​
org/​10.​1186/​s12873-​022-​00706-5.
Additional file 1.
Acknowledgments
We thank MD, PhD Tuomas Huttunen and MD, PhD Eija Junttila for their valuable comments on the manuscript.
Authors’ contributions
All authors took part in planning the study. P.V. and E.A. gathered the data. P.V.,
the corresponding author, was responsible for the data analysis and wrote the
original draft of the manuscript. All authors equally contributed to reviewing
and editing the draft. The author(s) read and approved the final manuscript.
Funding
This study was financially supported by the Competitive State Research
Financing of the Expert Responsibility area of Tampere University Hospital.
Availability of data and materials
Deidentified data will be preserved for 10 years after publication. Proposals for
data sharing should be directed to the corresponding author by email.

Declarations
Ethics approval and consent to participate
We designed the study in accordance with the Helsinki declaration. We
collected, controlled and processed the data in adherence to the European
Union General Data Protection Regulation. The Ethics Committee of Tampere
University Hospital approved the study (ETL R20082R). Emergency Response
Centre Agency Finland (HAK-21142) granted access to the emergency call
recordings. Due to the retrospective chart-review design of the study, the Ethics Committee of Tampere University Hospital waived the need for informed
consent.
Consent for publication
Not applicable.
Competing interests
The authors have no conflicts of interest.
Author details
1
Faculty of Medicine and Health Technology, Tampere University, Tampere,
Finland. 2 Department of Emergency, Emergency Medical Services, Centre
for Prehospital Emergency Care, Anaesthesia and Pain Medicine, Tampere

Vuorinen et al. BMC Emergency Medicine

(2022) 22:146

University Hospital, PO Box 2000, FI‑33521 Tampere, Finland. 3 Faculty of Social
Sciences, Tampere University, Tampere, Finland. 4 Department of Neurosciences and Rehabilitation, Tampere University Hospital, Tampere, Finland.

Page 9 of 9

15.

Received: 1 April 2022 Accepted: 8 August 2022
16.
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