Article

Basic life support training: Demonstration versus lecture – A randomised controlled trial

Camilla Hansen ^a^,^b^,^c, Camilla Bang ^a^,^b^,^c, Stinne Eika Rasmussen ^a, Mette Amalie Nebsbjerg ^a, Kasper G. Lauridsen ^a^,^b^,^c, Katrine Bjornshave Bomholt ^a, Kristian Krogh ^d^,^e, Bo Lofgren ^a^,^b^,^c^,^f^,^g^,?

^a Research Center for Emergency Medicine, Aarhus University Hospital, Palle Juul-Jensens Blvd. 161, 8200 Aarhus, Denmark

^b Department of Internal Medicine, Randers Regional Hospital, Skovlyvej 15, 8930 Randers, Denmark

^c Clinical Research Unit, Randers Regional Hospital, Skovlyvej 15, 8930 Randers, Denmark

^d Department of Anesthesia and Intensive Care, Aarhus University Hospital, Palle Juul-Jensens Blvd. 99, 8200 Aarhus, Denmark

^e Centre for Health Sciences Education, Aarhus University, Palle Juul-Jensens Blvd. 82, INCUBA Skejby building B, 8200 Aarhus, Denmark

^f Department of Clinical Medicine, Aarhus University, Palle Juul-Jensens Blvd. 82, INCUBA Skejby building 2, 8200 Aarhus, Denmark

^g Department of Cardiology, Aarhus University Hospital, Palle Juul-Jensens Blvd. 69, 8200 Aarhus, Denmark

a r t i c l e i n f o

Article history:

Received 20 January 2019

Received in revised form 11 May 2019

Accepted 3 June 2019

Keywords:

Cardiac arrest Cardiopulmonary resuscitation Teaching method

Basic life support

a b s t r a c t

Introduction: Basic life support (BLS) and the use of an Automated external defibrillator improve survival from cardiac arrest. The gold standard for teaching BLS/AED is yet to be identified. The aim of this study was to compare the learning outcome of an instructor-led demonstration with a formal lecture for introducing BLS/ AED skills. We hypothesized that a demonstration was superior to a lecture.

Methods: First year-medical students were randomised to either a demonstration or a lecture using PowerPoint(R) Presentation for skill introduction during European Resuscitation Council BLS/AED courses. Participants were skill-tested after training and required to perform all skills correctly to pass the test. Finally, all participants were asked to state their preferred teaching method.

Results: Overall, 247 participants were included in the analysis (demonstration group: 124, lecture group: 123). Pass rate was 63% in both groups, p = 1.00.

Both groups performed median compression rates within guidelines recommendations, p = 0.09. Mean com- pression depth was 55 mm (10 mm) in the demonstration group compared with 52 mm (10 mm) in the lecture group, p = 0.05. Median tidal volume was 265 (192, 447) ml and 405 (262, 578) ml, p b 0.001, respectively. The lecture group was 3 s faster at initiating BLS, p b 0.001. In total, 226 (91%) participants preferred demonstration on a manikin for introducing BLS/AED. Conclusion: There was no statistically significant difference in pass rate when comparing a demonstration with a lecture for introducing BLS/AED. The lecture group was slightly faster at initiating BLS. Most participants pre- ferred a demonstration as introduction.

Introduction

High-quality bystander cardiopulmonary resuscitation (CPR) and use of an Automated external defibrillator improve survival from cardiac arrest [1]. Trained laypeople are more likely to perform by- stander CPR compared to untrained individuals [2,3]. Dissemination of

Abbreviations: AED, automated external defibrillator; BLS, basic life support; CPR, cardiopulmonary resuscitation; ERC, European Resuscitation Council; SD, standard deviation.

* Corresponding author at: Department of Internal Medicine, Regional Hospital of Randers, 8930 Randers, NE, Denmark.

E-mail address: [email protected] (B. Lofgren).

basic life support (BLS) and AED skills is therefore crucial. Accordingly, CPR teaching methods have been identified as a research priority [4].

The European Resuscitation Council (ERC) offers BLS/AED courses based on the ERC Resuscitation guidelines [5]. The course uses the 4- stage teaching method, which breaks down the skill teaching process into four stages: I) Demonstration, II) Explanation, III) Formulation and IV) hands-on practice [6]. According to the ERC BLS/AED course rules, introduction of BLS/AED skills can be performed as either a real- time live instructor-led demonstration with subsequent instructor ex- planation [6] or a formal lecture using a standardised ERC PowerPoint(R) presentation [7]. An instructor-led demonstration can be performed without adding additional costs to the course and enables important visualisation of BLS/AED skills. However, instructors may unintention- ally leave out details or introduce faulty techniques. In contrast, the

https://doi.org/10.1016/j.ajem.2019.06.008

Stage I

Stage II

Stage III

Guided by participant

stage IV

Demonstration by participant

Demonstration group

Demonstration

Demonstration with explanations

Lecture group

use of a PowerPoint(R) guided lecture ensures a standardised presenta- tion of BLS/AED techniques in each course. The standard lecture format includes no video and therefore provides no visualised performance of BLS/AED skills. In general, a lecture is considered to yield a smaller learning outcome than a demonstration [8].

Formal lecture

Both demonstrations and lectures are commonly used in BLS/AED teaching [9,10]. Currently, no studies have compared skill performance when using the two training methods. The aim of this study was to com- pare the learning outcome of an instructor-led demonstration with a formal lecture for introducing BLS/AED skills. We hypothesized that a demonstration was superior to a lecture.

Methods

Study design and randomisation

Fig. 1. Course structure. The course structure was based on the 4-stage teaching method. In the demonstration group, stage I consisted of an instructor-led skill demonstration on a manikin, which was supplemented with explanations in stage II. In the lecture group, stage I and II consisted of a lecture. Stage III and IV were taught equally in the two groups.

This was a prospective randomised controlled superiority simulation study. Participants were randomised to BLS/AED training using either an instructor-led demonstration (intervention) or a lecture (control) for stage I and II of the four-stage teaching method. A co-investigator allo- cated participants 1:1 to the respective groups by drawing numbers from an envelope in block sizes of 24 per course.

Fig. 2. Participant flow diagram. We identified 296 eligible participants, of which 253 (85%) were included in the study. Although participants were screened before inclusion, six participants were still subsequently excluded according to exclusion criteria, leaving a total of 247 participants for study analysis.

Table 1

Participant demographics.

The table displays baseline demographics for participants in the demonstration group and the lecture group.

Participant demographics	Demonstration group	Lecture group	P-value
	(n = 124)	(n = 123)
Age, median (Q1, Q3)	21 (20, 22)	21 (20, 22)	0.78
Sex, female, n (%)	83 (67)	83 (67)	1.00
No previous CPR training, n (%)	8 (6)	7 (6)	1.00
Years since last CPR training^a, mean (SD)	2.9 (1.2)	2.9 (1.2)	0.86
CPR training besides driver’s license^b, n (%)	37 (30)	27 (22)	0.20
Previous job requiring CPR skills, n (%)	11 (9)	13 (11)	0.83
Has performed CPR in real life, n (%)	0 (0)	3 (2)	0.12
CPR = cardiopulmonary resuscitation.

^a Log-transformed data.

^b In Denmark, it is required to complete a mandatory CPR course when obtaining a driver’s license.

Participants and ethics

Participants were recruited from March 2016 through September 2016 among first year medical students attending a mandatory ERC BLS/AED course at Aarhus University, Aarhus, Denmark. Participants were blinded to the study intervention and told not to discuss course content with others.

Exclusion criteria were: completion of any CPR training within 12 months, holding a BLS instructor certificate or similar qualifications, having achieved a health care professional degree (e.g. nurse or physio- therapist) or physical inability to perform CPR.

A questionnaire was handed out to participants enquiring informa- tion on: gender, age, previous CPR training and whether the subject ever performed CPR during real cardiac arrest.

Oral and written consent was obtained. According to the Danish Act on Research Ethics Review of Health Research Projects, Act number 593 of 14 July 2011 section 14, approval from the Danish National Commit- tee on Biomedical Research Ethics was not required. Permission to per- form the study was granted by Aarhus University. The study complies with the Declaration of Helsinki.

Training methods

The overall course structure is depicted in Fig. 1. All instructors were certified ERC BLS/AED instructors. Throughout the course, four different instructors taught each team. The duration of both training methods was 3.5 h with a total skill introduction time of 30 min in each group.

In the demonstration group, instructors first demonstrated skills in real-time without any commentary (stage I), and then again with de- tailed explanation of each skill (stage II). In the lecture group, an instruc- tor held the lecture using the official ERC PowerPoint(R) Presentation translated into Danish [7]. The lecture consisted of key information about the BLS/AED algorithm, including a step-by-step explanation of each skill. The instructor followed a standardised script. In total, 8-12 study participants were present for the lecture or the demonstration (stage I and II) in each group. Medical students who declined to partic- ipate or were ineligible for study participation received introduction

given a standardised Cardiac arrest scenario and asked to react as in real life. An instructor acted as bystander and only assisted with sum- moning the Emergency Medical Services and subsequently retrieving an AED. Participants were asked to continue until stopped by instructors.

Evaluations were video-recorded and BLS quality data were col- lected via a computer with acquisition-software (AMBU(R) CPR Software, Ballerup, Denmark) connected to a standard torso resuscitation manikin without arms (AMBU(R) Man C, AMBU, Ballerup, Denmark) identical to the training manikin. The test AED was also identical to the training AED (CR+ AED-trainer, Physio Control, Redmond, WA, USA).

Before and after the course, participants assessed self-confidence in performing BLS and using an AED using a 5-point Likert-scale with one point representing the highest level of confidence (see Supplemen- tary file B). After the test, participants also reported overall learning out- come and evaluated the teaching method on a scale from one to ten, ten being excellent (see Supplementary file B). They were asked about per- ceived effectiveness of four different BLS/AED teaching methods (lec- ture, video, e-learning and demonstration on manikin), and finally, they were asked to choose which of the four methods they would pre- fer. Participants were enquired about four teaching methods in order not to disclose the teaching methods included in the study.

Outcome measures

The primary outcome was defined as overall pass rate in the two groups, i.e. the percentage of participants with the highest score (13 points). Secondary endpoints were: A) chest compression depth, rate, hand positioning and recoil, B) Tidal volume and percentage of success- ful rescue breathing attempts, C) Time to initiation of BLS and shock

Table 2

BLS/AED quality.

Data represent participants’ BLS/AED performance for the first three cycles of BLS. Listed are the proportions of participants performing each of the reported skills adequately in at least 2 of 3 cycles of BLS. Time to initiation of BLS and time to first shock are reported for both groups.

with the demonstration group.

Stage III and IV did not differ between the groups. Each group was subdivided into teams of four to six participants and two instructors. All teams were placed in separate rooms. In stage III, participants were asked to guide the instructor through the skills step by step. In stage IV, participants performed the practical skills. Instructors reinforced learning by correcting mistakes in participants’ instructions and performances.

BLS/AED quality Demonstration group

n = 123

Correct participant

performances^a:
Chest compression depth, n (%)	45 (37)	43 (36)	1.00
chest compression rate, n (%)	94 (76)	90 (75)	0.91
Hand positioning, n (%)	121 (98)	116 (97)	0.72
Full recoil, n (%)	96 (78)	94 (78)	1.00
Rescue breathing, n (%)	6 (5)	13 (11)	0.10

Time from scenario start to^b:

Lecture group

n = 120

P-value

Assessment

BLS/AED skills were assessed immediately after the course. A re- search assistant was present during each evaluation. Participants were

Initiation of BLS, sec, mean (SD) 43 (1.2) 40 (1.2) b0.001

Shock delivery, sec, mean (SD) 153 (1.1) 150 (1.1) 0.10

^a In at least 2 of 3 BLS cycles.

^b Log-transformed data.

A 80

Compression depth (mm)

B

150

Demonstration Lecture

100

Compressions per minute (min^-1)

Demonstration Lecture

C

1000

500

Tidal volume (mL)

Demonstration Lecture

Fig. 3. Chest compression depth, rate and tidal volume. Each dot represents a participant’s mean performance in terms of chest compression depth (A), rate (B) or tidal volume (C) based on all successful rescue breaths, defined as volume N0 ml, (C) for the first three cycles of BLS. Mean +- SD are depicted for chest compression depth and median with interquartile range are depicted for chest compression rate and tidal volume, respectively. The grey areas represent the ERC Guideline recommendations.[5]

delivery, D) Participants’ self-perceived skills and ratings of teaching methods.

Two ERC certified BLS/AED instructors, blinded to teaching methods, assessed all participants’ BLS/AED performances independently based on the video recordings. In case of disagreement, assessors reviewed the video together and came to a joint conclusion. BLS/AED skills were evaluated using the official ERC skill checklist (Supplementary file A) [11]. Each of the 13 skills were assessed individually as either ade- quately or inadequately performed. All skills should be adequately per- formed to pass the course. Adequate chest compressions were defined as at least two of three cycles of BLS with 30 (+-2) compressions per cycle, a rate of 100-120 min^-1, depth of 5-6 cm, and correct hand place- ment. Adequate rescue breaths were defined as two attempted rescue breaths per cycle, of which >=50% were efficient. Efficiency was defined as visible, but not excessive elevation of the manikin’s chest.

For BLS quality analysis, data on chest compressions (depth, rate and recoil) and rescue breathing (tidal volume) were retrieved for the first three full cycles of BLS. Single chest compressions at the beginning of each chest compression cycle with maximum depths b20 mm were cat- egorized as “leaning” and excluded from further analysis. The upper limit for full recoil was set at 5 mm. Correct tidal volume was defined as 500-600 ml of air in accordance with ERC guidelines [5]. Data on hand-positioning and time to initiation of BLS and shock delivery were acquired from video recordings.

Statistical analysis

Based on previous BLS/AED courses for first year medical students, we assumed a pass-rate of 90% for the demonstration group and 75% for the lecture group. Selecting an alpha-value of 0.05 and a power of 0.8, a total of 113 participants were needed in each group to detect the expected difference of 15%. Anticipating drop-out, the sample size was increased to 132 participants in each group and a total of 264 par- ticipants were required. Data were analysed for normality using Q-Q plots and histogram analysis. Parametric data are reported as mean (standard deviation; SD) and non-parametric data are reported as me- dian (25th, 75th-percentile; Q1, Q3). Categorical data are reported as numbers (percentage).

For the primary outcome, both a primary intention-to-treat and a secondary per-protocol analysis were performed. Secondary outcomes were analysed as intention-to-treat.

Normally distributed continuous data were compared using student’s t-test. Where continuous data conformed to normality after log-transformation, log-transformed results are reported. Non- parametric data were analysed using the Wilcoxon rank-sum test for between-group comparisons. Likert scale data were analysed as cate- gorical variables, as self-assessed confidence in skill performance was based on levels on agreement to statements rather than numbers on a numerical scale [12]. Categorical data were analysed using the Chi- square Test or Fisher’s Exact Test where appropriate. A P-value of

b0.05 was considered statistically significant. Data were analysed using R Statistics, version 3.1 [13].

Results

Participants

Enrolment and randomisation of participants are shown in Fig. 2. During the study period 334 first year medical students completed the BLS/AED course, of which 296 were eligible for inclusion. During the study period, data were not collected from 24 participants because the purpose of the study was mistakenly revealed prior to course start.

We included 253 participants and 247 were included in the analysis (Fig. 2). Table 1 shows demographics, which were similar for the two groups. Data for secondary outcomes were missing for four participants, and five participants from the lecture group received both teaching methods by error. To account for this, we performed an intention-to- treat as well as a per-protocol analysis.

Participants’ overall pass rate

In the intention-to-treat analysis, 78 (63%) participants in the dem- onstration group and 78 (63%) in the lecture group passed the test, p = 1.00.

Of the participants who failed, 42 (34%) in the demonstration group and 37 (30%) in the lecture group obtained 12 points, 3 (2%) and 6 (5%) obtained 11 points, and only 1 (1%) and 2 (2%) obtained 10 points or less, respectively. There was no statistical difference between the groups. In the per-protocol analysis, 63% passed in the demonstration group and 62% in the lecture group, p = 0.90. The distribution otherwise remained the same.

BLS/AED quality analysis

Overall BLS/AED quality is listed in Table 2.

mean compression depth was 55 mm (10 mm) in the demonstration group compared with 52 mm (10 mm) in the lecture group, p = 0.05 (Fig. 3). Median compression rates were 110 min^-1 (Q1:103, Q3:116 min^-1) and 112 min^-1 (Q1:106, Q3:118 min^-1), respectively, p = 0.09. Median tidal volume per successful rescue breath was 265 (192, 447) ml in the demonstration group compared with 405 (262,

578) ml in the lecture group, p b 0.001.

Participants’ self-confidence

Participants’ self-confidence improved over the course (Table 3). Although competence in both groups was statistically comparable at baseline, more participants in the demonstration group than in the lecture group reported highest level of self-confidence in performing BLS and using an AED after the course (72% versus 54%, p = 0.009).

Table 3

Self-confidence in BLS/AED skills. Participants were asked to state their level of agreement to the following sentence before and after the course: I feel confident in performing CPR (chest compressions, rescue breathing and using an AED).

Level of agreement	Before course			After course
	Demonstration^a (n = 123)	Lecture (n = 123)	P-value	Demonstration (n = 124)	Lecture^a (n = 122)	P-value
Strongly agree	7 (6%)	4 (3%)	0.54	89 (72%)	67 (54%)	0.009
Agree	37 (30%)	29 (24%)	0.31	33 (27%)	52 (42%)	0.01
Neither nor	41 (33%)	44 (36%)	0.79	2 (2%)	3 (2%)	1.00
Disagree	25 (20%)	33 (27%)	0.29	0	0	–
Strongly disagree	12 (10%)	12 (10%)	1.00	0	0	–

Numbers (%).

^a One participant did not answer.

Participants’ ratings of the teaching methods

When evaluating learning outcome from the course on a scale from one to ten (ten being excellent) both groups reported excellent out- come with median scores of 10 (9, 10), p = 0.15.

Both groups evaluated their teaching method as excellent with median scores of 10 (9, 10), p = 0.26. Yet, when given a choice between four different teaching methods for introducing BLS/AED skills, 226 (91%) of all participants preferred demonstration on a manikin.

Discussion

There was no statistically significant difference in pass rate when comparing a demonstration with a lecture for introducing BLS/AED skills. Only one in three participants performed correct chest compres- sion depth irrespective of training method. The lecture group was slightly faster at initiating BLS. Nevertheless, most participants pre- ferred a demonstration for introduction of BLS/AED skills.

We only found one study that has compared the effect of a demon- stration followed by case-based discussion with a lecture including video and PowerPoint(R) [14]. Both methods equally improved Cognitive skills among medical students, but BLS performance was not evaluated. However, a study demonstrated no significant difference in chest com- pression performance compared with the standard approach, when using a standardised video podcast for stage I and II of the 4-stage teach- ing method [15]. We demonstrate that BLS performance is also compa- rable when using demonstration or a lecture, although we expected a demonstration to be superior to a lecture. A possible explanation may be that both groups completed stage III and IV, which include guidance of the instructor through all BLS/AED skills and hands-on BLS/AED prac- tice. This may have compensated for lack of real-time visualisation of BLS/AED skills for stage I and II in the lecture group and allowed instruc- tors to correct many initial mistakes. Future studies may consider eval- uating participants before stage III and IV. We did not record any data on instructors’ self-perceived work load during stage III and IV or use any objective measures of corrected mistakes. This may be another impor- tant aspect to assess in future studies.

It took both groups approximately 40 s to initiate BLS. In comparison, a previous study examining BLS training programmes reported time to first compression of 49-58 s [16]. The lecture group was 3 s faster at ini- tiating BLS and delivering a shock than the demonstration group, although not significant at shock delivery. A possible explanation may be that participants in the demonstration group may have imitated in- structors’ actions as performed during initial demonstration, thus incor- porating certain time intervals into each action, e.g. “look-listen-feel” for breathing for maximum 10 s, following AED instructions in real-time etc. Notably, decreased time to initiation of BLS and shock delivery is associated with increased survival [17]. However, it is unknown if the difference of 3 s will change outcomes.

All other chest compression parameters were comparable between the groups. In contrast to instructor ratings, manikin data revealed that only about one third of participants performed correct compression depth with respect to ERC guidelines. The inconsistency between reported pass rates and objective measures of correctly performed chest compressions suggests that our instructors tend to overestimate BLS skill performance. This phenomenon has been observed in previous studies as well [18,19]. Similarly, the criterion “visible, but not excessive elevation of the manikin’s chest” for instructor assessment of correct res- cue breathing is subjective and may not correlate entirely with the nar- row 500-600 ml. We chose this method as it reflects current assessment practice at ERC BLS/AED courses.

We observed higher tidal volume along with a tendency towards more participants delivering correct tidal volume in the lecture group. Both groups demonstrated poor adherence to recommenda- tions for tidal volume in accordance with findings in previous studies [20,21]. As rescue breathing is important, particularly in cases of

asphyxial and long-term cardiac arrests, [22,23] methods to improve skill performance should be investigated. However, chest compres- sion quality remains the most important CPR determinant of patient outcome [24,25].

Before the course, there was no difference in self-confidence in BLS between the two groups. After the course, more participants in the dem- onstration group reported highest level of self-confidence in BLS, although this was not reflected in skill performance. This finding is interesting, as bystanders have reported fear of not performing BLS cor- rectly as reason for not initiating BLS in real life cardiac arrest [3]. Simi- larly, the majority of participants preferred demonstration on a manikin to a lecture for introducing BLS/AED skills irrespective of their training method.

A possible explanation may be that medical students share the com- mon belief that a lecture yields a smaller learning outcome than a dem- onstration [8]. Furthermore, a demonstration may result in higher self- confidence among participants, as they are presented with a visual reference for correct performance.

Currently, alternative teaching methods and modalities in resuscita- tion training are rising. The traditional instructor-led demonstration approach is challenged by an increasing number of studies focusing on self-instruction and media-supported training [14,15,20,21,26,27].

Although instructor-led demonstration has been suggested as a reference standard for the ERC BLS/AED provider course, [9,10] no gold standard for teaching resuscitation has yet been identified. The ERC guidelines support the use of different teaching modalities and suggest that training should target the needs of different types of learners [4].

Studies have shown that lectures are used for introducing BLS or AED in approximately 10-22% of ERC courses [9,10]. Our results support the use of both teaching methods for introduction of BLS/AED skills in resuscitation courses for medical students using the 4-stage teaching method. Whether this applies to other groups of BLS/AED learners is unknown.

Our data further suggest that current teaching methods in ERC BLS/ AED courses may be further improved, particularly concerning chest compression depth, rescue breathing and time to BLS and shock deliv- ery. More teaching options and modalities should be tested with the aim of improving the learning outcome from BLS/AED courses in the future.

Limitations and strengths

Our study population consisted of young first-year medical students. As such, we cannot infer on the effect of the training methods in other study populations, e.g. elderly laypersons.

To avoid pre-course learning, no before-course test was performed to establish baseline skill performance. However, this was a randomised study. Previous CPR training experience was similar between the two groups, supporting the assumption that skill performance would be comparable.

No evaluation of skill retention was performed. We can therefore not infer the Long-term effects of the two teaching methods.

Conclusions

A demonstration was not superior to a lecture for introducing BLS/ AED when followed by verbalization of skills and hands-on practice. The lecture group was slightly faster at initiating BLS. Nevertheless, more participants in the demonstration group felt highly confident in BLS after the course and most participants preferred demonstration on a manikin compared with a lecture for introducing BLS/AED.

Supplementary data to this article can be found online at https://doi. org/10.1016/j.ajem.2019.06.008.

Funding

Salary support for the lead author of the study was provided by Aar- hus University, Denmark. Office supplies were provided by Research Center for Emergency Medicine, Aarhus University Hospital, Denmark. The funding bodies were not involved in data collection, analysis or in- terpretation, nor did they participate in drafting of the scientific manuscript.

Declaration of Competing Interest

None to declare.

Acknowledgements

We thankfully acknowledge all instructors and medical students at Aarhus University, Denmark, who participated in the study.

Data statement

The research data are available upon request to the corresponding author.

References

AJEM

Basic life support training: Demonstration versus lecture – A randomised controlled trial

a r t i c l e i n f o

a b s t r a c t

Introduction

Methods