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Abstract
Background Self-instruction with a DVD and a simple personal manikin is an effective alternative to traditional basic life support (BLS) courses.
Objective To evaluate the effect of distributing DVD training kits to untrained laypersons. BLS skills were compared according to 2005 guidelines for resuscitation after 3.5 months with those obtained in untrained laypersons who completed the same course with instructor facilitation.
Methods BLS skills of 55 untrained laypersons were assessed using the Laerdal ResusciAnne and PC Skill Reporting System in a 3 min test and a total score (12–48 points) was calculated. The participants received a DVD training kit without instructions. The test was repeated after 3.5 months. Data were compared with data from a previous published study where participants completed the same course in groups with instructor facilitation.
Results There was no statistically significant difference in the total score after 3.5 months. The ‘DVD—self-instructor’ group obtained 33 (29–37) points and the ‘DVD—with instructor’ group obtained 34 (32–37) points, p=0.16. The ‘DVD—with instructor’ group performed significantly better in checking responsiveness and had a significantly shorter ‘total hands-off time’ (s) (85 (76–94) vs 96 (82–120), p=0.002) and delay until first compression or ventilation group (29 s (17–40) vs 33 s (22–48), p=0.04).
Conclusions Since no significant difference in total BLS score was found after 3.5 months between untrained laypersons who either completed a DVD-based BLS course in groups with instructor facilitation or received the same DVD training kit without instruction, the latter seems more efficient.
- Cardiac arrest
- basic life support (BLS)
- manikin
- training
- cardiac arrest
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Introduction
The year 2010 marked the 50th anniversary of cardiopulmonary resuscitation (CPR) with airway alignment, ventilations and external chest compressions,1 and thousands of lives have been saved by this technique. Indeed, if bystanders start basic life support (BLS) for a person with out-of-hospital cardiac arrest, the survival rate is doubled or tripled.2 Despite this and tremendous efforts in research, development of new treatments and regular evidence-based amendments to guidelines, the survival rate has remained essentially unchanged over the past three decades. The aggregate survival rate to hospital discharge from all-rhythm cardiac arrest recorded from different populations is between 7.6% and 10.7%.3 ,4
Contributing to these low figures is the fact that only one-third of subjects with an out-of-hospital cardiac arrest receive bystander BLS.5 Few are trained in BLS and those that are trained are not likely to witness an OHCA. Different training modalities have been developed to make BLS training more available. Self-instruction with a DVD and a simple personal manikin (eg, MiniAnne, Laerdal Medical, Stavanger, Norway) has shown that a similar or better skill acquisition and retention are achieved than by traditional hour-long BLS courses.6–13 These studies have included participants who were instructed either in groups or alone with an observer and this demands certain logistics, since the participants have to be at a specific place at a specific time.
As an alternative, the training kit could be delivered without any instructions and the recipients could then use the training kit in their homes at a convenient time. There are two potential limitations to distribution in this way. First, the recipient of the training kit might not use it at all and secondly, skill acquisition might not be the same when there is no one to facilitate the training and answer questions.
The aim of this study was to evaluate the effect on BLS skills of distributing BLS training kits to untrained laypersons with a request to use the kit at home. We assessed the BLS skills obtained 3.5 months after receipt of the training kit (MiniAnne). The data from this ‘DVD—self-instructor’ group were then compared with data from a previous published study in which participants completed the MiniAnne course in groups and with instructor facilitation (the ‘DVD—with instructor’ group).14 The primary end point was the total score obtained in the two groups (‘DVD—self-instructor group’ and ‘DVD—with instructor’ group) at evaluation of BLS skills after 3.5 months.
We hypothesised that the BLS performance would be better in the ‘DVD—with instructor’ group.
Methods
We invited laypersons at a municipal office and a television station on the Danish island of Bornholm (population 43 000, area 588 km2), to participate in an investigation of the effectiveness of a BLS training kit. They received no payment, and the employers at each location agreed that all employees could take part in the study during work time. In the previous study, participants were laypersons from a high school and a municipal centre for people excluded from mainstream society.14
Consent was obtained from each individual who had not participated in any BLS training during the past 5 years. Baseline BLS skills were individually assessed according to the 2005 guidelines for resuscitation. The assessment was performed with a resuscitation manikin connected to a laptop with Laerdal PC SkillReporting System version 2.0 (Laerdal Medical, Stavanger, Norway). This system recorded the quantitative data on hand placement, compression depth, total number of compressions and ventilations, ventilation volume, total hands-off time and delay until first compression or ventilation. Before assessment we decided that hand position was incorrect if one compression was in the wrong position, the correct compression/ventilation ratio was 30±2:2 and ideally, BLS should be initiated within 30 s, thus leaving 2.5 min for compressions and ventilations. An optimal 180 compressions and 12 ventilations could be achieved within this timeframe.
One medical doctor (European Resuscitation Councils-certified BLS/AED instructor and advanced life support provider) obtained ordinal quantitative data. This included whether the subject checked for responsiveness by talking and shaking, opened the airway, checked for respiration, called for help and the compression/ventilation ratio. The acceptable standards for performance of the subject were calling for help within the first minute; delay was the time until first compression or ventilation and participants who attempted a ratio of 30:2 were registered as such also if ventilations were unsuccessful. The investigator registered data on a form during assessment and data were later entered into a database.
Before the start of the 3 min assessment the participant was told to imagine that “you are waiting for a bus late in the evening in a rural village. The only other person around is an elderly person, also awaiting the bus. Suddenly the person collapses in front of you. Now, do what you would do in a real situation”. Further information about the victim's condition was only provided if the subject asked specific questions after having performed a relevant action.
The data were registered on a scoring sheet, derived from the Cardiff test,15 which is an international checklist designed to evaluate resuscitation performance. We have updated it to the European Resuscitation Councils guidelines for adult BLS 2005.2 In our version the scores are given in 12 different categories, either by assessment of the investigator or by data collected by a laptop connected to a training manikin. The points that were given in the 12 categories can be seen in table 1. The total score ranged from 12 to 48 points. By dividing the average score (−12) with the maximal score (48−12) the percentage of the maximal achievable was calculated. The primary end point was total score but the different variables were compared as well.
Assessment of basic life support skills in laypersons, who have not received basic life support training within the previous 5 years
After the primary assessment each participant received a MiniAnne (Laerdal Medical, Stavanger, Norway) training kit, which is a 24 min DVD-based resuscitation course with an inflatable personal resuscitation manikin. The only information provided was that the box contained an inflatable manikin and a DVD with instructions for BLS. They were encouraged to use the training kit as much as possible and to allow friends and relatives to use it as well.
In the ‘DVD—with instructor’ group, the MiniAnne course was completed in groups with instructor facilitation right after the primary assessment.14
Three and a half months after the initial assessment the participants were called in for a 3 min follow-up assessment of skill acquisition. This was done without prior warning. At the reassessment they completed a form about the use of the training kit provided.
Data from the laypersons in the ‘DVD—with instructor’ group have been reported in detail in a previous study.14
For statistical analysis the SAS System V.9.1.3 v2 (SAS Institute Inc) was used.
For continuous data we report median with 25–75% range and a Mann–Whitney test was used for comparison between the ‘DVD—with instructor’ group and the ‘DVD—self-instructor’ group. Proportions were compared using χ² test. p Values <0.05 were considered statistically significant.
Sample size was calculated as follows: a difference of three points in the total score at 3.5 months using the Cardiff scale was considered clinically relevant because a reduction of three points in either one of the variables could reduce the survival chances, and a reduction of one point in three different variables would cause suboptimal performance. In a previous study of medical students an SD of 4.2 points was found.16 This SD was expected to be higher in laypersons and the calculation was therefore based on an SD of 5. Using a significance level of 0.05 we calculated that a power of 85% would be reached if we included 100 people. Our previous study included 68 people and 56 attended the follow-up assessment. In this study we included 55 participants to allow for dropouts.
Results
The ‘DVD—self-instructor’ group consisted of 55 participants from a municipal office and a television station. They had a median age of 45 (40–53) years and 62% were male. Twenty-two per cent had no education beyond high school. Ten participants were not tested at the 3.5 months follow-up: two were sick, three had a day off, three were attending a course and two participants' employment had ended. In total, 45 (82%) were reassessed.
The ‘DVD—with instructor’ group consisted of 68 participants from a high school and a municipal centre for people excluded from mainstream society. The median age was 18 (17–46) years and 47% were male. Sixty-two per cent were high school students. Reassessment was possible in 56 (82%) (figure 1).14
Flow chart on the inclusion of patients. Data on the ‘DVD—with instructor’ group have been published previously.14
There was no statistically significant difference in the total score at 3.5 months follow-up between the two groups: the ‘DVD—self-instructor’ group 33 (29–37) points (57% of the maximum score) versus the ‘DVD—with instructor’ group 34 (32–37) points (61% of the maximum score), p=0.16.
The ‘DVD—with instructor’ group performed significantly better than the ‘DVD—self-instructor’ group in the variable ‘checks responsiveness by talking’ (64% vs 44%, (p=0.046) and had a significantly shorter ‘total hands-off time’ (s) (85 (76–94) vs 96 (82–120), p=0.002). The delay (s) until first compression or ventilation was also significantly shorter in the ‘DVD—with instructor’ group (29 (17–40) vs 33 (22–48), p=0.04).
The ‘DVD—self-instructor’ group performed significantly better than the ‘DVD—with instructor’ group in the variable ‘checks respiration’ (89% vs 70%, p=0.02).
Thirteen (29%) had used the training manikin and the DVD themselves at home, eight (18%) had used only the manikin and four (9%) had used only the DVD. There was no statistically significant difference (p=0.09) in the improvement in the total score between the group who used the training kit (5 (2–8)) and the group who did not (3 (1–6)).
Among those who had spent time training in BLS, an average of 41 min was used. Fifteen (33%) had used their MiniAnne to train a total of 38 others. The 45 training kits were used to train a total of 63 different people, thus a multiplier effect of 1.4.
Discussion
We found no significant difference in the total BLS skill score after 3.5 months between laypersons who completed an instructor-facilitated MiniAnne course and laypersons who received the MiniAnne training kit with a request to use it at home without instruction. The ‘DVD—with instructor’ group performed significantly better than the ‘DVD—self-instructor’ group in the two variables ‘total hands-off time’ and ‘delay until first compression or ventilation’. Maybe the presence of the instructor and other students during the training session prompted the participants to start CPR quicker and to have a shorter hands-off time.
It is a strength of our study that the participants in both groups were recruited by approaching laypersons instead of advertising because we could then minimise a positive selection bias (volunteers are likely to be more motivated). Among those eligible for participation no one declined to participate and no one present at the day of reassessment declined to be tested. At the day of the study everyone present at the two different sites were included in the study. We only excluded those who had had any BLS training during the past 5 years. As no one declined to participate and the recruitment percentage thereby was 100%, we eliminated any selection bias.
It was a limitation that 20 (44%) had neither used the DVD nor the manikin, but their data were included in the analysis, since we wanted to describe the overall effect of disseminating training kits in a population and not the effect in a selected highly motivated population. Another important limitation is the considerable age difference between the two groups because better retention has been demonstrated in young subjects.17–20 In our study we hypothesised that the BLS performance would be better in the ‘DVD—with instructor’ group and this group also had the lowest mean age, but we found no significant difference in the overall skills between the two groups. Perhaps there was a higher motivation for learning BLS in the ‘DVD—self-instructor’ group since they were older and thus more likely to witness a cardiac arrest. Education beyond high school has also been shown to be positively related to skill retention.19 The majority in the ‘DVD—with instructor’ group were high school students whereas 22% in the ‘DVD—self-instructor’ group had no education beyond high school. A randomised study would have allowed us to obtain a more similar distribution. On the other hand, there would have been practical problems and other obstacles since the participants knew each other and would have talked about the study and BLS in the time period between the primary and secondary assessment.
Finally, the follow-up rate was 82%, but we decided not to schedule another assessment day because the participants then would have been pre-warned of the test. It is also a possibility that the pretesting could have induced a positive learning effect, but both groups were subject to the same pretest.
Twenty-five (56%) subjects had used the DVD and/or the manikin at home, which is comparable to another study in which videotapes with CPR instruction were mailed to households where 50% reported that at least one person in the household had viewed the videotape.21
Skill improvement tended to be greater in the group who had used the training kit and a significantly lower score was found in those who did not use the DVD.
Surprisingly, there was a median skill improvement of three points in the group who neither had used the DVD nor the manikin. This might be due to a positive effect of testing on learning outcome22 or it might be explained by the Hawthorne effect. In a preliminary study that evaluated a web-based self-training program for BLS there was no significant correlation between the time spent using the program and the quality of performance.23 A study24 that examined attitude changes (competence, confidence and willingness to perform CPR) as a function of different CPR training modalities found that the control group, who were merely tested and not trained, had similar attitude changes to those of the trained groups. They conclude that the mere exposure to CPR testing can induce a positive attitude and it may be this same phenomenon that we see in our study, where the group who did not use the training kit still had an improved CPR performance.
The MiniAnne training kit has great potential in disseminating BLS training in a community because the participants keep the kit. The multiplier effect was 1.4. We did not assess the skill improvement in the second tier, but it might be similar to that in the first tier, since the only intervention in the first tier was a test scenario without any feedback. In the ‘DVD—with instructor’ group there was a similar multiplier effect (1.6).14
For our primary end point, the total score, we found no significant difference between the ‘DVD—with instructor’ course and the ‘DVD—self-instructor’ course. The ‘DVD—with instructor’ course requires more logistics and participants have to be gathered at a certain time and in a suitable room with a big screen. Given the opportunity, some participants may not participate actively in the course owing to the classroom setting, which may remind them of school. On the other hand, those who do attend the course in ‘DVD—with instructor’ groups might benefit from the social interaction with other participants and if they participate with school or work they might talk about the course afterwards. In a study about e-learning for maintenance of advanced life support competence, the lack of social interaction was the primary factor influencing use of the program.25
Conclusion
Since no significant difference in total BLS score was found after 3.5 months between untrained laypersons who either completed a DVD-based BLS course in groups with instructor facilitation or received the same DVD training kit without instruction, the latter seems more efficient.
Acknowledgments
We thank TrygFonden (Denmark) for supplying the MiniAnne training mainikins. We also thank journalist Rune Holm, TV2/Bornholm, Denmark, for his work in coordinating the project.
References
Footnotes
Competing interests AMN received an unrestricted research grant from the TrygFonden foundation, Denmark. Laerdal Medical supplied the resuscitation manikin, ResusciAnne and the Laerdal PC SkillReporting System version 2.0. Neither TrygFonden nor Laerdal Medical took any part in designing the study, analysing the data or approving the manuscript. None of the remaining authors have any declared conflicts of interest.
Provenance and peer review Not commissioned; externally peer reviewed.
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