Dispatcher-Assisted Cardiopulmonary Resuscitation: A Randomized Controlled Trial of Low-Dose, High-Frequency Simulation-Based Training and the Impact on Real Out-of-Hospital Cardiac Arrest Calls
Phase: NA
Conditions: Out-Of-Hospital Cardiac Arrest
Sponsor: Emergency Medical Services, Capital Region, Denmark

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Dispatcher-Assisted Cardiopulmonary Resuscitation: A Randomized 
Controlled Trial of Low-Dose, High-Frequency Simulation-Based Training 
and the Impact on Real Out-of-Hospital Cardiac Arrest Calls  
General Information 
Primary Sponsor and Principal Investigator: Freddy Lippert, MD, Associate Professor, Copenhagen Emergency 
Medical Services, and The Faculty of Health and Medical Sciences, Department of Clinical Medicine, University 
of Copenhagen, Denmark 
Responsible Investigator: Freddy Lippert, MD, Associate Professor 
Funding: The study is financed by an unrestricted research grant from the Danish foundation TrygFonden. 
Trial registration 
The protocol will be registered on ClinicalTrials.gov prior to enrolment and randomisation of participants. All 
items from the World Health Organization Trial Registration Data Set will be reported. 
Investigators: 
Oscar Rosenkrantz, Copenhagen Emergency Medical Services, and Copenhagen Academy for Medical Education 
and Simulation, Capital Region of Denmark and University of Copenhagen, Copenhagen, Denmark 
Kristine Elisabeth Eberhard, Copenhagen Emergency Medical Services, and Copenhagen Academy for Medical 
Education and Simulation, Capital Region of Denmark and University of Copenhagen, Copenhagen, Denmark 
Roselil Maria Oelrich, Copenhagen Emergency Medical Services, University of Copenhagen, Copenhagen, 
Denmark 
Anne Lippert, Copenhagen Academy for Medical Education and Simulation, Capital Region of Denmark and 
University of Copenhagen, Copenhagen, Denmark 
Gitte Linderoth, Copenhagen Emergency Medical Services, and Department of Anaesthesia and Intensive Care, 
Copenhagen University Hospital – Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark 
Anders Granholm, Department of Intensive Care 4131, Copenhagen University Hospital – Rigshospitalet, 
Copenhagen, Denmark 
Annette Kjær Ersbøll, National Institute of Public Health, University of Southern Denmark, Copenhagen, 
Denmark 
Fredrik Folke, Copenhagen Emergency Medical Services, and Herlev Gentofte Hospital, Department of 
Cardiology, and The Faculty of Health and Medical Sciences, Department of Clinical Medicine, University of 
Copenhagen, Denmark 
Participants will be enrolled and randomized in the start of September 2019. 
Data collection is planned to start in mid-September 2019 and run for 13 weeks. 
 

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TABLE OF CONTENTS 
1. BACKGROUND ............................................................................................................................ 4 
2. STUDY AIMS AND HYPOTHESES ............................................................................................ 5 
3. STUDY METHODS ...................................................................................................................... 5 
4. DATA COLLECTION AND CLASSIFICATION ...................................................................... 14 
5. ETHICAL ASPECTS .................................................................................................................. 17 
6. TIME SCHEDULE ..................................................................................................................... 17 
7. DISSEMINATION OF RESULTS ............................................................................................. 18 
8. FINANCING ............................................................................................................................... 18 
9. RELATIONSHIP BETWEEN TRYGFONDEN AND INVESTIGATORS ............................. 18 
10. TRIAL ORGANISATION .......................................................................................................... 19 
 
 
 

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Abbreviations:  
AHA American Heart Association 
AED automated external defibrillator 
BLS basic life support 
CBD criteria-based dispatch 
CPR cardiopulmonary resuscitation  
DA-CPR dispatcher-assisted cardiopulmonary resuscitation  
EMD emergency medical dispatcher  
EMDC emergency medical dispatch centre 
EMS emergency medical service  
ERC European Resuscitation Council  
LDHF low-dose, high-frequency 
LLEAP Laerdal Learning Application 
OHCA out-of-hospital cardiac arrest  
RQI-T Resuscitation Quality Improvement for Telecommunicators 
 
 

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BACKGROUND 
The chance of surviving an out-of-hospital cardiac arrest (OHCA) is reduced by 7-10% each minute 
defibrillation is delayed[1]. If early cardiopulmonary resuscitation (CPR) is provided in the time 
period until defibrillation, the chance of survival is only reduced by 3-4% per minute[1, 2]. 
Dispatcher-assisted CPR (DA-CPR) can strengthen the chain of survival by increasing the 
bystander CPR rate and quality as well as diminishing the time to CPR[3-8]. Additionally, the 
emergency medical dispatcher (EMD) can act as a team leader and assist the bystanders in 
providing high-quality CPR. Several studies from multiple countries and continents have found 
increased survival with DA-CPR[3, 4, 7, 9-11]. The European Resuscitation Council (ERC) and 
American Heart Association (AHA) have in recent years and with the latest guidelines, emphasised 
the importance of the EMDs in OHCAs, and the Global Resuscitation Alliance (GRA) recommends 
DA-CPR as one of the “10 Steps for Improving Survival From Sudden Cardiac Arrest”[12-16].  
Around the world, dispatcher protocols have been developed to ensure the quality of the EMDs’ 
support, and studies show that the implementation of such protocols increase bystander CPR and 
survival[6, 17, 18]. In Denmark, Danish Index for Emergency Care (Dansk Indeks for Akuthjælp) is 
a triage and decision tool for EMDs to guide the caller and decide the appropriate emergency 
medical service (EMS) response[19, 20]. The Danish version is a translation and adaptation of the 
Norwegian Index for Emergency Medical Assistance Norwegian (Norsk Indeks for Medisinsk 
Nødhjelp), version 3, which was based on the principles of the criteria-based dispatch (CBD) 
system developed in King County, Seattle, USA[21]. One of the fundamental principles of many 
CBD systems is a set of all-caller questions at the beginning of every call, to rule out or recognise a 
cardiac arrest. This concept has been described as “No-No-Go”. The EMD is to determine whether 
the patient is conscious and if not, determine whether the patient breathing normally[22]. If the 
caller responds “no” to both consciousness and normal breathing, the EMD must send an EMS 
response as well as provide DA-CPR instructions without further delay or elaborating questions. 
Thus, with two simple questions in mind, the EMD can recognise or rule out a potential cardiac 
arrest, activate the appropriate EMS response and initiate bystander.  
Various methods are used in training EMDs to recognise cardiac arrests and provide quality DA-
CPR instructions: dispatcher-to-dispatcher audits of emergency call records, simulation-based 
training, case reviews, mentor groups, reporting, and feedback[23, 24]. Introduction of structured 
CPR instruction protocols have also been shown to have a positive effect on bystander CPR, and 

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thus survival, but protocol adherence is not perfect[25-27]. While their role in the Chain of Survival 
is paramount, each EMDs often handle relatively few OHCA calls every year, thus regular training 
is essential to maintain competences[28, 29]. The Global Resuscitation Alliance has, through the 
Resuscitation Academy (Seattle, Washington, USA), together with The American Heart 
Association (AHA) and Laerdal Medical (Stavanger, Norway), developed a simulation training 
program for EMDs that meets these needs: structured training that requires only few resources. 
Despite the vast literature on medical simulation training, there is a knowledge gap regarding the 
potential benefits of low-dose, high-frequency (LDHF) training of EMDs using structured feedback. 
The potential benefits have not yet been investigated in real OHCA. This study will obtain evidence 
to the use of LDHF simulation-based training for EMDs. 
STUDY AIMS AND HYPOTHESES 
The aims of this study are: 
1) To measure the effect of LDHF simulation-based training on the quality of DA-CPR in a 
simulation setting. 
2) To measure the effect of LDHF simulation-based training on the quality of DA-CPR in real 
OHCA calls. 
We hypothesise that LDHF simulation-based training will increase the quality of DA-CPR in the 
intervention group in a simulation setting and that this improvement is transferred to real OHCA 
calls – although the effect in real OHCA calls might be smaller due to the complexity of some calls. 
We hypothesise that this improvement can be detected as a decrease in time to first bystander 
compression (TTFC), an increase in clarification of consciousness and breathing without asking 
additional questions, a decrease in time to recognition of cardiac arrest, and an increase in calls 
where the EMD provide DA-CPR instructions on patients in cardiac arrest. 
STUDY METHODS 
STUDY DESIGN 
The study is randomised controlled trial comparing LDHF simulation-based training to standard 
quality improvement of the EMDs in a single centre. This protocol is structured according to the 
SPIRIT 2013 statement and the study will be reported in compliance with the CONSORT 2010 
Statement[30, 31]. We choose EMDs receiving standard quality improvement as the comparator 
group, to reflect a representative cohort of the EMDs not exposed to the LDHF simulation-based 
training program.  

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OUTCOME MEASURES 
Primary outcome: 
1. Time from a call is taken by EMD to first bystander compression (seconds) 
Secondary outcomes: 
2. EMD clarifies status of consciousness and breathing before asking any additional questions 
(yes/no) 
3. Time from a call is taken to the recognition of cardiac arrest (seconds)  
4. EMD starts DA-CPR instructions (yes/no) 
5. Time from a call is taken to EMD starts DA-CPR instructions (seconds) 
6. EMD is assertive when starting CPR instructions (yes/no) 
7. EMD starts DA-CPR instructions on patient without cardiac arrest (yes/no) 
All outcomes will be assessed in both simulated calls and real OHCA calls. 
STUDY SETTINGS 
The study will be conducted at Copenhagen EMS, the emergency medical dispatch centre (EMDC) 
covering the Capital Region of Denmark. The Capital Region of Denmark covers Greater 
Copenhagen including suburbs and has a population of approximately 1.84 million people covering 
an area of 2559 km2[32]. The European emergency phone number 1-1-2 life-threatening calls and 
injuries is the countrywide, which connects the caller to a switchboard identifying location and need 
for police, fire department, or medical assistance. Medical emergency calls in the Capital Region of 
Denmark are transferred to the Copenhagen EMS, which receives approximately 105,000 
emergency calls annually, of which approximately 1,200 (~1.0%) are OHCAs. The call taker is a 
paramedic or a registered nurse. 
PARTICIPANTS 
All approximately 70 employed EMDs at the Copenhagen EMS, guiding callers in emergency 
situations, will be assessed for eligibility, except for the four EMDs facilitating the simulations (see 
below).  
The following eligibility criteria apply: 
 
Inclusion criteria: 
- EMD employed at the Copenhagen EMS at the time of enrolment 

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Exclusion criteria: 
- Mean working time as call taker at Copenhagen EMS < 8 hours/week 
- Planned employment cessation at the Copenhagen EMS during the data collection period 
- Planned leave from work longer than four weeks during the data collection period 
- Starting employment at the Copenhagen EMS during the study period 
 
The flow of participants will be illustrated using a CONSORT 2010 Flow Diagram (Figure 1). 
 
We expect to be able to obtain a follow-up on ~60 EMDs due to an anticipated loss to follow-up of 
~8 %. Simulation-based dispatcher training for EMDs in the intervention arm will be held during 
the EMDs’ regular paid shifts. Demographic data will be presented separately in each group. 
Numeric data will be presented as medians with interquartile ranges, and categorical data will be 
presented as numbers with percentage. The following demographic data regarding EMDs will be 
collected: age (years), sex (male/female), profession (paramedic/nurse), experience as an EMD 
(years).  
Participation in the study is voluntary, without additional economic or other compensation. Both 
written and verbal informed consent of all EMDs will be obtained prior to randomisation. Further, 
EMDs can, at any point withdraw their consent and discontinue their participation without 
providing any reason. 
Figure 1 – CONSORT 2010 Flow Diagram 

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LDHF: Low-dose, high-frequency; QI: Quality improvement; SIM PRE: Simulation pre-
intervention; SIM POST: Simulation post-intervention; I: intervention group; C: comparison 
group; (n= ) will be listed at the end of the study. 
 
RANDOMISATION PROTOCOL 
After enrolment and consent from the EMDs, the EMDs will be randomly assigned to receive either 
LDHF simulation-based dispatcher training (intervention arm) or no LDHF simulation-based 
dispatcher training (comparison arm). 
The EMDs will be randomly assigned to intervention or comparison group in a 1:1 ratio. 
Randomisation will be stratified by the EMDs’ medical backgrounds (paramedic, approximately 
30% of the EMDs, or registered nurse, approximately 70% of the EMDs), to balance the number of 
EMDs with different medical backgrounds randomly assigned to each arm. All the EMDs will be 

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randomised at the same time using a randomisation programme written in R (R Core Team, R 
Foundation for Statistical Computing, Vienna, Austria). A random seed (ensuring that the same 
randomisation sequence can be re-generated) will be selected by a person not involved in the study, 
and the same person will run the script. This is done once after all eligible EMDs have either 
decided to participate or not. Thus, all eligible, consenting EMDs will be randomised at the same 
time and the randomisation scheme will be immediately delivered to the study group, without need 
for allocation concealment as the random sequence is generated at the same time as all participants 
are assigned to one of the two trial arms. The research group and the participants will not be blinded 
to the allocation, except for the study statistician (A.K.E.), who will conduct all analyses blinded to 
the intervention group. Thus, the study statistician will not have access to the randomisation scheme 
or the random seed and will receive a dataset with the actual groups replaced with the numbers 0 
and 1.  
SAMPLE SIZE 
The required sample size (number of real OHCA calls) has been calculated based on the primary 
outcome; time from a call is taken to first compression, with 32 EMDs in each arm. This calculation 
is based on an expected inclusion of 70 EMDs and an anticipated loss to follow-up of ~8%, thus, 
follow-up of 64 EMDs is projected. Based on OHCA calls in November-December 2018, mean 
(standard deviation; SD) TTFC was calculated as 174 (111) seconds where TTFC initiated later 
than 10 minutes after call were excluded. With a comparison group mean of 174 (SD 111) seconds 
for TTFC and an expected TTFC in the intervention group at mean 120 seconds, we estimate a need 
of 160 real OHCA calls in each of the two arms to have 90% power to reject our null hypothesis of 
no change in TTFC with at a two-sided test and alpha level of 5%. An assumed intra-class 
correlation at 5% between TTFC within the same dispatcher is used in the calculation [33]. To 
reduce the risk of underpowering the study due to a smaller reduction or greater standard deviation, 
we aim to include data from 175 calls in each group but will include all calls in the study period. 
With approximately 125 OHCA calls at the EMDC per month, this gives an expected data 
collection period for OHCA calls of 12-13 weeks. If data collection produces fewer calls than 
expected, data collection will continue until 350 calls are collected in total, ending data collection a 
full week after the aim is reached. Calculations are based on the TTFC data from Copenhagen EMS 
in two consecutive months in late 2018. A 31% decrease in TTFC is set as the clinically relevant 
decrease based on the AHA’s DA-CPR minimal acceptable performance recommendations of 

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median amount of time <120 seconds from address acquisition to first DA-CPR directed 
compression[34]. 
SIMULATION TRAINING SET-UP 
The intervention group begins LDHF dispatcher training with one introduction week followed by 
12 weeks of LDHF training. EMDs not working during the introduction week, will start their 
introduction week when they have their first shift after the study has started. Their LDHF training 
period will end at the same time as the rest of the EMDs and they will therefore receive fewer 
training sessions overall. The simulation-based training sessions take place at the EMDC, at extra 
workstations set-up as ordinary EMD workstations in an out-of-the-way area. Before each session, 
the EMD is informed about the simulation call and receives instructions concerning technical 
differences from a regular call (see appendix 1). The instructor acts as a “standardised caller”, 
guided by a computer program. This program, the Danish version of Resuscitation Quality 
Improvement for Telecommunicators (RQI-T) (Laerdal Medical AS, Stavanger, Norway), is a 
training program for DA-CPR based on the simulation platform Laerdal Learning Application 
(LLEAP). This modified version of the RQI-T program has, one test scenario, one data collection 
scenario and six different cardiac arrests scenarios as well as a feedback checklist based on the 
Danish dispatcher protocol Danish Index for Emergency Care. The instructor facilitates a 
standardised scenario with a scripted course of events including scripted lines. Only scenarios 
where callers are laypersons not trained in basic life support (BLS) will be given during the study. 
According to Danish Index for Emergency Care the EMDs should then guide in compression only 
CPR – they will therefore not be trained in ventilations instructions. Some scenarios include an 
automated external defibrillator (AED). All EMDs will be presented for a short test scenario 
without feedback for familiarisation and then for the simulation data collection scenario with 
feedback. In the training phase, EMDs in the intervention group will be presented to the scenarios 
one through six in numerical order and then start over, going through the same six scenarios again 
approximately halfway through the study period. The simulation data collection scenario is the 
same for in the first and last week. Every time the EMD achieves one of the items on the feedback 
checklist, the scenario will inform the instructor about the next action or line – ensuring 
standardisation of the scenarios. When the call ends, the instructor provides feedback to the EMD, 
in-person, using the integrated structured feedback module that presents the results of the feedback 
checklist. Results from the feedback module will be used to assess the EMD’s performance from 
training session to training session to provide adaptive feedback. Therefore, an adaptive approach to 

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feedback will be used by registering three feedback points in a logbook and presenting these key 
points from last simulation before each new simulation. Each simulation session takes 
approximately 20 minutes, including introduction and feedback. 
During the study period, all regular quality improvement (QI) activities, such as self-audits, case 
reviews, mentor groups, and status meetings will continue for all EMDs. Four EMDs (two 
paramedics and two registered nurses) will, prior to assessment of eligibility of all other EMDs, be 
asked by the research group to facilitate the simulation-based training. These four EMDs will not be 
assessed for eligibility to participate in the study. 
DATA COLLECTION 
Collection of data from simulated OHCA calls 
The introduction week consists of one short test scenario without feedback (for familiarisation), 
followed by one scenario with structured feedback (scenario “DATA”) – the audio recording from 
the second scenario will form the data: “simulation pre-intervention – intervention group” (SIM 
PRE-I). During LDHF training, the intervention group will receive one scenario per week in the 
following 12 weeks. In week 13 (last week), a scenario (scenario “DATA”) will be presented to the 
intervention group forming the data: “simulation post-intervention – intervention group” (SIM 
POST–I). 
The comparison group will also receive the same short test scenario without feedback (for 
familiarisation) followed by one scenario with structured feedback (scenario “DATA”) – the audio 
recording from the second scenario will form the data: “simulation pre-intervention – comparison 
group” (SIM PRE-C). In week 13 (last week), a scenario (scenario “DATA”) will be presented to 
the comparison group forming the data: “simulation post-intervention – comparison group” (SIM 
POST–C). A timeline overview is given in figure 2. 
The data set used for the primary analysis is a full analysis set only excluding EMDs if no 
intervention is applied at all or if no data is available after randomisation. 
Figure 2 – timeline 

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OHCA: Out-of-hospital cardiac arrest; min: minimum; SIM PRE: simulation pre-intervention; SIM 
POST: simulation post-intervention; I: intervention group; C: comparison group 
 
Collection of data from real OHCA calls 
Real OHCA calls handled by the EMDs in the intervention group will only be retrieved for 
evaluation after the individual EMDs have received their first simulation training session while real 
OHCA calls handled by the EMDs in the comparison group will be retrieved for evaluation from 
the first day of the introduction week. 
Real OHCA calls from week one through 13 – the introduction week and the 12-week training 
period – handled by the enrolled EMDs will be retrieved and evaluated according to the outcome 
measures – these calls will form the data “real OHCA – intervention group” (OHCA-I) and the 
“real OHCA – comparison group” (OHCA-C). 
Only calls handled by EMDs included in the study will be included in the data analysis.  
The study group has adopted the definition of a recognised cardiac arrest as well as the data 
collection strategy recommended in the systematic review by Viereck et al. [29]: 
• Recognition is assessed by evaluating emergency call recordings. 
• Recognition of OHCA is defined as a call where the caller or the EMD, expresses the 
presence of "OHCA" or the need for "CPR" or an "AED". 
• Exclusion criteria for calls are: 
o EMS-witnessed OHCA. 
o Missing/corrupted emergency call recording within 120 seconds. 

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o Calls where the patient was obviously alive during the call. 
o Calls where bystander CPR was initiated prior to the emergency call. 
o Calls where the caller was unable to assess the patient (e.g. caller not being together 
with the patient). 
• Data will be reported using a standardised flowchart (see figure 3). 
All calls meeting exclusion criteria will be excluded from all analysis. 
In addition, all paediatric OHCA calls are excluded as the training alone is for adult cases. 
Paediatric calls are defined as patient age <18 years. 
All OHCA calls are initially identified by including all EMD call recordings marked as OHCA at 
the Copenhagen EMS and by comparing these to the Danish Cardiac Arrest Registry. The data 
collection of 1-1-2 emergency calls for OHCA recognition is shown in figure 3. 
Numeric data will be presented as medians with interquartile ranges, and categorical data will be 
presented as numbers with percentage. The following demographic data regarding patient will be 
collected: age (years), sex (male/female), etiology of cardiac arrest (cardiac or noncardiac), location 
(public/private), witnessed (yes/no), time to EMS arrival (seconds). 
Figure 3 – Flowchart describing the data collection process of 1-1-2 emergency calls for OHCA 
recognition. 

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OHCA: Out-of-hospital cardiac arrest; EMS: Emergency medical services; CPR: 
Cardiopulmonary resuscitation; (n= ) will be listed at the end of the study. 
 
DATA COLLECTION AND CLASSIFICATION 
Both simulated and real OHCA calls outcomes will be reported by a questionnaire filled in by 
auditors listening to recordings of all included calls. Auditors evaluating calls are not involved in 
writing the protocol or manuscript, and the audio recordings will be blinded to group allocation. 
The questionnaire is a modified version of the Cardiac Arrest Registry to Enhance Survival 
(CARES) DA-CPR Data Dictionary protocol for OHCA calls, which originally consisted of 22 
questions whereby the quality of the call is evaluated[35]. During the review of audio recordings, 
the 31 assessment points in the modified questionnaire, table 1, will be documented.  Instructions 
for coding in appendix 2, ensure consistency during the review process. 
To assess quality of data review, an inter-rater reliability test will be performed on a sample of calls 
using Cohen’s kappa for binary outcomes and intra-class correlation coefficient for continuous 
outcomes[36]. Auditors allocated to perform the audio reviews will receive two hours of training to 
practice the documentation process. 

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Table 1 – Questionnaire content for simulated and real OHCA calls 
 
Assessment points 
Result (time or 
yes/no/NA) 
Time of EMD addressing caller 
(seconds) 
Cardiac arrest before arrival of EMS? 
(yes/no) 
CPR already in progress? 
(yes/no) 
Consciousness addressed? 
(yes/no) 
Patient conscious? 
(yes/no) 
Breathing addressed? 
(yes/no) 
Patient breathing normally? 
(yes/no) 
“No - No - Go” approach, used? 
(yes/no) 
Normal/abnormal breathing addressed? 
(yes/no) 
Need for CPR recognized? 
(yes/no) 
Time of recognition 
(seconds) 
BLS competence addressed? 
(yes/no) 
CPR instructions started? 
(yes/no) 
Time of instructions started 
(seconds) 
Barriers to CPR? 
(yes/no) 
EMD assertive when giving CPR instructions? 
(yes/no) 
Speed and depth of compressions addressed? 
(yes/no) 
Using encouraging and motivating techniques when instructing? 
(yes/no) 
Chest compressions started? 
(yes/no) 
Time to first compression 
(seconds) 
AED addressed? 
(yes/no) 
AED connected to the patient? 
(yes/no) 
Did the AED deliver a shock to the patient? 
(yes/no) 
Cardiac arrest witnessed by another person? 
(yes/no) 
Call continued until EMS arrival? 
(yes/no) 
Male sex of caller? 
(yes/no) 
Caller is alone at the time of call? 
(yes/no) 
Caller is a relative or friend of the patient? 
(yes/no) 
Caller has easy access to assess the patient? 
(yes/no) 

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Caller is emotionally distressed? 
(yes/no) 
Other comments? 
 
 
STATISTICS 
The primary outcome analyses investigate the effect of the intervention (LDHF training) on time to 
first compression in real OHCA calls. This continuous primary outcome will be presented 
descriptively with median and interquartile. The effect of the intervention will be tested using a 
Poisson regression of the incidence rate of first compression. First compression is the outcome and 
the logarithm of time to first compression is the offset value. To account for the hierarchical data 
structure with OHCA nested within EMDs a random effect of EMDs within intervention is included 
in the model. The relative effect of the intervention compared to the comparison group on time to 
first compression is presented as an incidence rate ratio (IRR) and a corresponding 95% confidence 
interval.  The frequency of OHCA calls will vary between EMDs due to the random call 
distribution. 
The binary secondary outcomes in real OHCAs: EMD did not ask irrelevant questions prior to 
clarifying consciousness/breathing, EMD recognises cardiac arrest, EMD starts DA-CPR 
instructions, bystander starts CPR and EMD starts DA-CPR instructions on non-cardiac arrest, will 
be presented descriptively with numbers and percentages. The effect of the intervention will be 
tested using a logistic regression analysis with a random effect of EMDs within intervention 
included in the model. The relative effect will be presented as odds ratios (OR) with 95% 
confidence intervals. 
The continuous secondary outcomes related to the simulations: time to first compression, will be 
presented descriptively with median and interquartile. The binary secondary outcomes related to the 
simulation: EMD did not ask irrelevant questions prior to clarifying consciousness/breathing, EMD 
addressed BLS competence, EMD assertive or passive when giving CPR instructions, EMD 
addressed speed and depth of compressions, EMD using encouraging and motivating techniques 
when instructing, will be presented descriptively with numbers and percentages. The effect of the 
intervention will be tested for SIM POST-I versus SIM POST-C adjusted for the baseline (SIM 
PRE-I + SIM PRE-C) and presented as odds ratio with a 95% confidence interval. 
A difference for the primary and secondary outcomes, except the outcome EMD starts DA-CPR 
instructions on patient without cardiac arrest (yes/no), between simulation data from the two groups 

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after the training period – SIM POST-I and SIM POST-C – will be tested. Additionally, we will test 
for a difference in the outcome measures before and after training for each group. 
A two-sided alpha level of 5% is considered statistically significant. 
Incidence, sensitivity and positive predictive value of OHCA recognition will be presented. 
Annette Kjær Ersbøll, National Institute of Public Health, University of Southern Denmark, 
Copenhagen, Denmark, will be responsible for the statistics – and will refine the existing statistical 
protocol. The final statistical analysis plan will be completed prior to the start of data collection. 
ETHICAL ASPECTS 
The study is registered by the Danish Data Protection Agency via The Capital Region of Denmark 
(J.No.: VD-2018-28, I-Suite No.: 6222). The study has also been registered with the Danish Patient 
Safety Authority (3-3013-2721/1). The Regional Danish Ethical Committee waived a formal review 
of the study (J.No.: H-19041425). 
Individual Participant Data (IPD) Sharing Statement according to ICMJE Requirements: 
Will individual participant data be available 
(including data dictionaries)?  
Yes 
What data in particular will be shared?  
Individual participant data that underlie the 
results reported in the article, after 
deidentification (text, tables, figures, and 
appendices). 
What other documents will be available?  
Study Protocol, Statistical and Analysis Plan, 
Informed Consent Form, Clinical Study Report, 
Analytic Code. 
When will data be available (start and end 
dates)?  
Immediately following publication. Until 31st 
of December 2021. 
With whom?  
Anyone who wishes to access the data. 
For what types of analyses?  
Any purpose. 
By what mechanism will data be made 
available?  
Data are available Until 31st of December 2021 
at (link to be included after publication).  
 
TIME SCHEDULE 
Starting mid-September 2019, data collection and LDHF training will continue for 13-weeks until 
the start December 2019. Upon enrolment written consent is obtained, and all EMDs will be 

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randomised at the same time, approximately one week prior to study start. Analysis of data and 
writing of manuscript is expected to finish in late 2020.  
DISSEMINATION OF RESULTS 
The results will be submitted to an international peer-reviewed journal and presented at relevant 
congresses, regardless of findings. The protocol will be made publicly available before data 
collection begins. 
FINANCING 
The study is financed by an unrestricted research grant from TrygFonden.  
Table 2 – Budget  
 
Budget item 
Cost (DKK) 
Training of four EMDs as simulation instructors 
13,152 DKK 
Randomisation 
1,176 DKK 
Extra staffing at the EMDC during the one-week introduction week 
28,770 DKK 
Extra staffing at the EMDC during the 12-week training/project period 
105,216 DKK 
Equipment 
8,000 DKK 
Data extraction of simulation tests 
32,941 DKK 
Data extraction from real OHCA calls 
22,058 DKK 
Scholarship, four months 
40,000 DKK 
Conference presentation 
12,060 DKK 
Open access publication 
19,697 DKK 
 
 
Total 
283,071 DKK 
 
All hours for simulation-based training of the EMDs in the intervention group are registered as 
extra costs since the training is in addition to the usual quality improvement activities and therefore 
not part of the scheduled hours. In addition, the hours are budgeted to avoid that the training, and 
thus, the data quality is compromised by the lack of capacity for the EMDs to leave their 
workstations to participate in the study.  
 
RELATIONSHIP BETWEEN TRYGFONDEN AND INVESTIGATORS 

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19 
Investigators Freddy Lippert, Kristine Elisabeth Eberhard Anne Lippert, Gitte Linderoth, Anders 
Granholm, Annette Kjær Ersbøll and Fredrik Folke has previously received grants from 
TrygFonden. The investigators are otherwise independent of TrygFonden. 
TRIAL ORGANISATION  
Principal investigator 
Freddy Lippert, MD, Associate Professor, CEO 
 
Copenhagen Emergency Medical Services 
Telegrafvej 5, opgang 2, 3.sal 
2750 Ballerup 
 
The Faculty of Health and Medical Sciences, Department of Clinical Medicine 
University of Copenhagen 
Blegdamsvej 3B 2200 København N 
 
Freddy.Lippert@Regionh.dk 
0045- 38698000 
 
Sub-Investigators: 
Associate Professor Freddy Lippert, Copenhagen Emergency Medical Services, and The Faculty of Health 
and Medical Sciences, Department of Clinical Medicine, University of Copenhagen, Denmark 
Medical student and research assistant Oscar Rosenkrantz, Copenhagen Emergency Medical Services, and 
Copenhagen Academy for Medical Education and Simulation, Capital Region of Denmark and University of 
Copenhagen, Copenhagen, Denmark  
Dr. Kristine Elisabeth Eberhard, Copenhagen Emergency Medical Services, and Copenhagen Academy 
for Medical Education and Simulation, Capital Region of Denmark and University of Copenhagen, 
Copenhagen, Denmark 
Emergency medical technician and research assistant Roselil Maria Oelrich, Copenhagen Emergency 
Medical Services, University of Copenhagen, Copenhagen, Denmark 
Dr. Anne Lippert, Copenhagen Academy for Medical Education and Simulation, Capital Region of 
Denmark and University of Copenhagen, Copenhagen, Denmark. 
Dr. Gitte Linderoth, Copenhagen Emergency Medical Services, and Department of Anaesthesia and 
Intensive Care, Copenhagen University Hospital – Bispebjerg and Frederiksberg Hospital, Copenhagen, 

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Denmark 
Medical student and researcher Anders Granholm, Department of Intensive Care 4131, Copenhagen 
University Hospital – Rigshospitalet, Copenhagen, Denmark. 
Professor Annette Kjær Ersbøll, National Institute of Public Health, University of Southern Denmark, 
Copenhagen, Denmark 
Assistant Professor Fredrik Folke, Copenhagen Emergency Medical Services, and Herlev Gentofte 
Hospital, Department of Cardiology, and The Faculty of Health and Medical Sciences, Department of 
Clinical Medicine, University of Copenhagen, Denmark 
 

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