Conflict of Interest Declaration
The ILCOR Continuous Evidence Evaluation process is guided by a rigorous ILCOR Conflict of Interest policy. The following Task Force members and other authors were recused from the discussion as they declared a conflict of interest: none applicable.
The following Task Force members and other authors declared an intellectual conflict of interest and this was acknowledged and managed by the Task Force Chairs and Conflict of Interest committees: Andy Lockey, Farhan Bhanji, Adam Cheng, Jan Breckwoldt.
CoSTR Citation
Yeung J, Djarv T, Sawyer T, Hsieh M, Lockey A, Bray J, Bhanji F, Bigham B, Breckwoldt J, Cheng A, Duff J, Glerup Lauridsen K, Gilfoyle E, Iwami T, Ma M, Monsieurs K, Okamoto D, Pellegrino J, Finn J, Greif R on behalf of the EIT Task Force and the NLS Task Force as collaborators.
The use of Spaced Learning compared with Massed Learning among learners taking a resuscitation or first aid course Consensus on Science with Treatment Recommendations [Internet] Brussels, Belgium: International Liaison Committee on Resuscitation (ILCOR) Education, Implementation and Teams Task Force, 2020 January 3. Available from: http://ilcor.org
Methodological Preamble
The continuous evidence evaluation process for the production of Consensus on Science with Treatment Recommendations (CoSTR) started with a systematic review (Yeung, 2019, PROSPERO -CRD42019150358) conducted by an expert systematic review team with the involvement of clinical content experts (Hsieh M, Greif R, Sawyer T). Evidence for adult, pediatric and neonatal literature was sought and considered by the Education, Implementation and Teams (EIT) Task Force. These data were taken into account when formulating the Treatment Recommendations.
We used the definition of “spaced” learning from the AHA scientific statement on education science: “Spaced or distributed practice involves the separation of training into several discrete sessions over a prolonged period with measurable intervals between training sessions (typically weeks to months) {Cheng 2018 82} We used the definition of “massed learning” from the AHA scientific statement on education science: “massed practice involves a single period of training (yearly or longer) without rest over hours or days.” {Cheng 2018 82}
Whilst the PICOST did not specifically address the timing of retraining, we included studies comparing “spaced” with “massed” learning in contexts of re-training (refresher training).
We identified two main types of comparisons in the literature. The first type examined the use of spaced learning which involve the separation of training into several discrete sessions over a prolonged period with measurable intervals between training sessions (typically weeks to months). The learning content can be distributed across different sessions or repeated at each session. The number of repetitions and time intervals between repetitions can vary. The second type examined the use of booster training which describes distributed practice after initial completion of training and is generally related to low-frequency tasks such as the provision of CPR. The terms just-in-time training, just-in-place training, and refreshers describe training are included in this category.
There was high heterogeneity among studies including clinical heterogeneity (such as types, format of intervention, methods of outcome assessments), and methodologic heterogeneity (outcome assessments, duration of follow-up, timing of assessment). We were unable to perform a meta-analysis and have conducted a narrative synthesis of the findings. This synthesis is structured around each outcome and spaced learning and booster training are discussed separately.
PICOST
The PICOST (Population, Intervention, Comparator, Outcome, Study Designs and Timeframe)
Population: All learners taking resuscitation courses (all course types and all age groups) and/or first aid courses.
Intervention: Training or retraining which is distributed over time (“spaced” learning).
Comparators: Training provided at one single time point (“massed” learning).
Outcomes: Educational outcomes (skill performance 1 year after course conclusion; skill performance between course conclusion and 1 year; knowledge at course conclusion) and clinical outcome (quality of performance in actual resuscitations; patient survival with favorable neurologic outcome)
Study Designs: Randomized controlled trials (RCTs) and non-randomized studies (non-randomized controlled trials, interrupted time series, controlled before-and-after studies, cohort studies) were eligible for inclusion. All original research articles (both prospective and retrospective) were included with no language restrictions. Unpublished studies (e.g., conference abstracts, trial protocols) were excluded.
Timeframe: All years and all languages were included as long as there was an English abstract. Literature search updated to December 2, 2019.
PROSPERO Registration CRD42019150358
Consensus on Science
Seventeen studies in courses with mannequins and simulation were included in the narrative synthesis: 13 randomised studies {Patocka 2019 73; Anderson 2019 153; Lin 2018 6;, Kurosawa 2014 610; Tabangin 2018 163; Sullivan 2015 8; Oermann 2011 447;, Ernst 2014 505; Montgomery 2012 9; Kardong-Edgren 2012 9; Nishiyama 2015 56;Cepeda Brito 2017 354; Bender 2014 664} and 4 non-randomised studies {Patocka 2015 6; O'Donnell 1993 193; Breckwoldt 2016 249; Mduma 2015 1}. The included studies covered a range of resuscitation courses: 8 studies in basic life support {Sullivan 2015 8; Lin 2018 6; Nishiyama 2015 56; O’Donnell 1993 193; Andersen 2019 153; Montgomery 2012 9;Kardong-Edgren 2012 9; and Oermann 2011 447} with the latter 3 studies reporting results from same cohort of participants; 3 studies in pediatric advanced life support {Patocka 2019 73; 6; Kurosawa 2014 610}; 5 studies in neonatal life support {Tabangin 2018 163; Mduma 2015 1;Bender 2014 664; Ernst 2014 505; Cepeda Brito 2017 354} and 1 study in Emergency Medicine skills course {Breckwoldt 2016 249}.
In all identified studies, practical skills were assessed using mannequins.
The overall certainty of evidence was rated as very low for all outcomes primarily due to a very serious risk of bias. The individual studies were all at moderate to serious risk of bias due to confounding. Because of this, and a high degree of clinical heterogeneity (such as types, format of intervention, methods of outcome assessments), and methodologic heterogeneity (outcome assessments, duration of follow-up, timing of assessment), no meta-analyses could be performed.
For the critical outcome of skill performance 1 year after course conclusion, we identified very low certainty of evidence (downgraded for risk of bias, inconsistency and imprecision) from four RCTs {Lin 2018 6; Andersen 2019 153; Oermann 2011 447; Nishiyama 2015 56} which all reported the use of spaced learning in basic life support to evaluate the number of participants able to provide chest compression of adequate depth (defined as >50mm) at 1 year. One RCT {Lin 2018 6} n=87 reported more participants were able to perform chest compressions of adequate depth with spaced learning compared to massed learning. At 12 months testing, spaced training group was superior to the control group for proportion of excellent CPR (control: 6/41 (14.6%), intervention 25/46 (54.3%), p < 0.001, OR 6.94 (95%CI 2.45 to 19.69). This study also reported improvement in other quality of chest compressions measures: percentage of chest compression rate (100-120/min) improved from 78.0 (95%CI 70.8 to 85.1) to 92.7 (95%CI 86.0 to 99.4); percentage of chest compressions with complete recoil from 86.5 (95%CI 81.6 to 91.4) to 97.4 (95%CI 92.8 to 100.0). Similar improvements were also reported in paediatric CPR parameters.
In booster training, three RCTs {Andersen 2019 153; Oermann 2011 447; Nishiyama 2105 56} n=790 reported more participants were able to provide chest compression of adequate depth compared to no booster training. One RCT {Andersen 2019 153} compared booster training of different frequency (monthly, 3 monthly, 6 monthly, annual). This study reported improved chest compression performance across all booster groups; with monthly booster training provided the best skill performance but highest attrition rate. Participants who trained monthly had a significantly higher rate of ‘excellent’ CPR performance (15/26, 58%) than those in all other groups (12/46, 26% in the 3-month group, p = 0.008; 10/47, 21% in the 6-month group, p = 0.002; and 7/48, 15% in the 12-month group, p < 0.001). Excellent CPR was defined as a two-minute CPR session where three metrics were achieved: 1) 90% of compressions with correct depth (50–60 mm), 2) 90% of compressions with correct rate (100–120/minute), and 3) 90% of compressions with full chest recoil. The Oermann study {Oermann 2011 447} also reported improved CPR performance in participants who received brief monthly practice compared to no monthly practice. In the booster training group, students’ mean compression depth was within acceptable range (mean 40.3mm SD 6.6) with 59.2% (SD 36.6) of compressions with adequate depth and no skill decay over the 12 months (p=0.31). In contrast, the control group had a significant loss of ability to compress with adequate depth at 12 months (mean 36.5mm SD 7.7) and only 36.5% (SD 33.6) of compressions with adequate depth (p=0.004). With booster training, students in the spaced learning group had significantly higher percentage of ventilations with adequate volume (booster 52.2% SD 30.9 vs no booster 38.5% SD 36.1, p<0.001). At 12 months the mean ventilation volume was 565.4ml (SD 147.8) for the booster group compared with mean ventilation volumes of 430.7ml (SD 231.7) for no booster group (p<0.0001). In a randomised study, Nishiyama et al compared BLS skill retention laypeople trained with 45min DVD based program with and without 15min refresher/booster training at 6 months {Nishiyama 2015 56}. During a 2 minute evaluation performed at 12 months, the number of total chest compressions was significantly greater in the booster group than in no booster group (booster mean 182.0 SD 41.7 vs no booster mean 142.0 SD 59.1, p < 0.001). The number of appropriate chest compressions (with depth over 50mm, correct hand position, complete recoil) performed was significantly greater in the booster group than in the no booster group (booster mean 68.9 SD 72.3 vs no booster mean 36.3 SD 50.8, p = 0.009). Time without chest compressions was also significantly shorter in booster group (booster mean 16.1 SD 2.1 s vs no booster 26.9 SD 3.7 s, p < 0.001). There were no significant differences in time to first chest compression between the two groups (booster mean 29.6 SD 16.7 s vs no booster mean 34.4 ± 17.8 s, p = 0.172) and AED operations.
For the critical outcome of skill performance between course conclusion and 1 year, we identified very low certainty of evidence (downgraded for risk of bias and imprecision) from two RCTs {Lin 2018 6; Oermann 2011 447}, n=201, for number of participants able to perform chest compressions with adequate depth (>50mm) at 6 months.
In a randomised trial, Lin et al {Lin 2018 6} reported: the percentage of spaced learning participants who were able to perform chest compressions of adequate depth as mean 83.2 (95% CI 74.4 to 92.1) compared to the control group mean 58.0 (95%CI 48.5 to 67.4), group difference mean 25.3 (95%CI 12.0 to 38.2); the percentage of spaced learning participants able to perform chest compressions of correct rate mean 95.5 (95%CI 90.0 to 100.0) compared to the control mean 79.3 (95%CI 73.3 to 85.3), group difference mean 16.2 (95%CI 8.1 to 24.4); the percentage of spaced learning participants able to perform chest compressions with the complete chest recoil mean 97.4 (95%CI 94.1 to 100.0) compared to mean 88.9 (95%CI 85.3 to 92.4), group difference mean 8.6 (95%CI 3.7 to 13.4). Similar superior performance was reported in the spaced learning group across all testing time points (3, 6, 9 and 12 months).
A second study also reported improved CPR performance in participants who received brief monthly practice compared to no monthly practice {Oermann 2011 447}. In the booster training group, the mean compression depths was maintained during 12 months of the study and ranged from 38.6mm (SD 6.7) at 3 months to 40.3mm (SD 6.6) at 12 months. In the no booster group, there was a significant skill decay with ability to compress with adequate depth, the mean depth at 9 months was 39.6mm (SD 6.8) and at 12 months was 36.5mm (SD 7.7, p = 0.004). With booster training, students in the spaced learning group improved their ability to ventilate with an adequate volume (6 months mean ventilation volume 514.0 mL (SD = 208.4) ml, 12 months mean ventilation volume was 620.7 mL (SD = 211.0)). In the control group, the mean ventilation volumes remained less than the recommended minimum (500ml) throughout the 12 months.
Other studies reporting skill performance between course conclusion and 1 year
Spaced learning (3 studies)
Three studies examined spaced learning in pediatric advanced life support.
The first study {Kurosawa 2014 610} recruited healthcare professionals and found improved clinical performance score - maximum score of 42 made up of 21 items (each item was scored as: 0 = not performed; 1 = performed inappropriately or not in a timely manner; and 2 = performed correctly and in a timely manner). Scores in the spaced learning group increased (pre 16.3±4.1 to post 22.4±3.9) compared with scores in the standard massed learning group (pre 14.3±4.7 to post 14.9±4.4, p = 0.006). Improvement was also found in the Behavioral Assessment Tool post training but did not reach statistical significance (p = 0.49).
The second study {Patocka 2019 73} randomised EMS providers to either a spaced (four weekly sessions) or massed format (two sequential days). At 3 months testing, Infant and adult chest compressions were similar in both groups but bag mask ventilation (BMV) and intraosseous insertion (IO) performance was superior in spaced learning group (spaced learning group BMV score mean 2.2 (SD 7), P = 0.005, IO score mean 3.1 (SD 0.5), P = 0.04; massed learning group BMV score mean 1.8 (SD 0.5), P = 0.98) IO score mean 2.7 (SD 0.2), P = 0.98).
In the third study, the same research group randomised medical students to a pediatric resuscitation course in either a spaced or massed format {Patocka 2015 6}. Four weeks following course completion participants were tested with a knowledge exam and their ability to perform bag-valve mask ventilation, intra-osseous insertion and chest compressions. The study found no significant difference in knowledge and overall performance but there was a trend towards more critical procedural steps performed by spaced learning group.
Booster learning (7 studies)
Sullivan at al randomised nurses into four groups: standard AHA training (C) and three groups that participated in 15 min in-situ IHCA training sessions every two (2M), three (3M) or six months (6M){Sullivan 2015 8}. The study found more frequent training was associated with decreased median time (in seconds) to starting compressions (standard: 33 (IQR 25–40) vs. 6 months: 21 (IQR 15–26) vs. 3 months: 14 (IQR 10–20) vs. 2 months: 13 (IQR 9–20); p < 0.001) and to defibrillation (standard: 157 (IQR 140–254) vs. 6 months: 138 (IQR 107–158) vs. 3 months: 115 (IQR 101–119) vs. 2 months: 109 (IQR 98–129); p < 0.001].
Randomising nursing students to monthly booster training or no booster training, Kardong-Edgren and colleagues reported higher percentage of compressions and ventilations without errors in booster group (percentage of correct mean chest compressions (Booster group mean 49.2 (SD 33.2) no booster group mean 39.7 (SD 34.8), p=0.003), percentage of correct ventilation (Booster group mean 48.0 (SD 32.3) no booster group mean 36.7 (SD 33.7), p<0.0001) {Kardong-Edgren 2012 9}. In the same cohort, participants also reported high satisfaction with the course {Montgomery 2012 9}.
O’Donnell also compared monthly booster training, 3 monthly booster training and no booster training in 100 nursing students undertaking BLS courses {O’Donnell 1993 193}. They found improved knowledge in participant booster learning group but did not find improved skill performance at 6 months (theory score monthly practice mean 11.5/14, 3 monthly practice 10.68/14, no practice 9.50/14, p=0.05).
Repeated booster practice was tested in neonatal resuscitation by Tabangin, who randomised neonatal hospital providers to monthly practice for 6 months vs three consecutive practices at 3, 5 and 6 months {Tabangin 2018 163}. The study concluded that repeated monthly testing resulted in improvements and maintenance of performance. Participants in monthly practice group scored 1.3 points (SE 0.42) higher on the OSCE than those who practiced less frequently. Over 6 months, monthly practice group had 2.9 times greater odds of passing on the first attempt compared with the group that practiced less frequently.
Also in neonatal resuscitation, Ernst et al randomised students training in neonatal intubation to standard training, weekly booster training or 4-weekly booster training {Ernst 2014 505}. Booster training improved all aspects of neonatal intubation performance, including choosing the correct equipment, properly performing the skill steps, length of time to successful intubation, and success rate, for novice health care providers in a simulation setting. Post training, median preparation score (maximum 11) for weekly group (median 9 IQR 8.0-9.5), and consecutive day (median 8.0 IQR 7.5-9.0) were significantly higher than control group (median 7.0 IQR 6.0-8.0), p<0.001. Post training performance score (maximum 8) was also significantly higher in weekly (median 7.0 IQR 6.5-7.5) and consecutive day (median 7.0 IQR 6.0-7.5) compared to control group (median 5.5 IQR 4.0-6.0), p<0.001). First-attempt intubation success improvements from baseline to the final assessment: from 3 participants to 11 (20% increase) in the standard group, from 6 participants to 26 (62% increase) in the weekly practice group, and from 4 participants to 29 (67% increase) in the consecutive day practice group (P < .001 for all groups). First-attempt intubation times also improved between the baseline and final assessments for participants in the two practice groups (weekly mean 27 seconds decrease from 42.5 to 15.5 seconds, consecutive day mean 11.3 seconds decrease from 31.3 to 20.0 seconds, control mean 6.5 seconds increase from 23.5 to
30.0 seconds, P < .001). The researchers were unable to demonstrate whether one type of booster training was superior.
Bender et al conducted a RCT comparing booster training 9 months after a neonatal resuscitation training program with no booster training. In simulation testing at 15 months, the booster group scored significantly higher in procedural scores (out of maximum score of 107) (71.6 versus 64.4, p=0.02) and teamwork behaviors (out of maximum score of 25) (18.8 versus 16.2, p=0.02). No difference in knowledge scores was found {Bender 2014 664}.
Cepada Brito randomised students in a neonatal resuscitation program to rolling refreshers booster training or no booster training {Cepeda Brito 2017 354}. Participants in booster training reported higher confidence in their performance at 6 months but this was not statistically significant.
For the important outcome of knowledge at course conclusion, we found very low certainty evidence (downgraded for risk of bias and imprecision) from three cohort studies. Breckwoldt and colleagues designed an emergency medicine intensive course of 26 teaching hours and compared the knowledge of 156 students for a course delivered over 4.5 days, compared with a course delivered over 3.0 days {Breckwoldt 2016 249}. At course conclusion, knowledge was tested with video-case based simulation. After the course, participants’ procedural knowledge was assessed by a specifically developed video-case based key-feature test (KF-test). Participants from the spaced version reached a mean of 14.8 (SD 2.0) out of 22 points, compared to 13.7 (SD 2.0) in the massed version (p = 0.002). In a randomised controlled trial of spaced versus massed learning in EMS providers, a 33-question standardized Heart and Stroke Foundation of Canada PALS MCQ test was used post-training and 3-months post-course {Patocka 2019 73}. In the spaced group there was no decay in the mean MCQ score 3-months post course compared to the immediate post-course score (post, 30.3 + 0.5 vs post-3-months 29.7 0.5; P= 0.39) however there was a statistically significant decay in the MCQ scores in the massed training condition (post, 31.1 0.5 vs post-3-months 29.6 0.5;P= 0.04).
O’Donnell compared monthly booster training, 3 monthly booster training and no booster training in 100 nursing students undertaking BLS courses {O’Donnell 1993 193}. They found improved knowledge in participant booster learning group but did not find improved skill performance at 6 months (theory score monthly practice mean 11.5/14, 3 monthly practice 10.68/14, no practice 9.50/14, p=0.05)
For the important outcome of quality of performance in actual resuscitations, we did not identify any studies.
For the important outcome of patient survival with favorable neurologic outcome, we did not identify any studies.
Whilst we did not find any study reporting performance at clinical resuscitation and patient survival with favorable neurological outcome, there was evidence from one observational study in the impact of booster training on delivery room management of the newborn {Mduma 2015 1}. This study assessed the impact of frequent brief (3–5 min weekly) on-site simulation training on newborn management in the delivery room and the potential impact on 24-hr neonatal mortality. The number of stimulated neonates increased from 712 (14.5%) to 785 (16.3%) (p = 0.016), those suctioned increased from 634 (13.0%) to 762 (15.8%) (p ≤ 0.0005). Mortality at 24-hr decreased from 11.1/1000 to 7.2/1000 (p = 0.040).
Treatment Recommendations
For learners undertaking resuscitation courses, we suggest that spaced learning (training or retraining distributed over time) may be used instead of massed learning (training provided at one single time point) (weak recommendation, very low certainty of evidence).
Justification and Evidence to Decision Framework Highlights
There is growing evidence suggesting that spaced learning can improve skill retention (performance 1 year after course conclusion), skill performance (performance between course completion and 1 year) and knowledge at course completion. We did not find any evidence to support either spaced or massed learning in skill performance during actual resuscitations or patient survival with favorable neurological outcomes.
In making this recommendation, the EIT taskforce (in collaboration with NLS taskforce) considered the following:
- Our review has only found very low certainty evidence to support spaced learning in resuscitation education derived mainly from basic life support, pediatric and neonatal life support courses. Nevertheless, the taskforce is of the opinion that the benefits of spaced learning demonstrated in other areas of education would also apply in resuscitation training.
- Our review did not inspect the optimal format of spaced learning or effect of different retraining intervals. Any training intervention should be designed to deliver the learning objectives specific to a course and it is unlikely that one specific format, design or duration would fit all resuscitation training courses.
- There was limited data from two studies which reported improved human factors with spaced learning {Kurosawa 2014 610; Bender 2014 664}.
- There may be concerns about increased costs or resource use due to organisation required for faculty, equipment and learners to implement spaced learning {Andersen 2019 153}. However there is evidence from the grey literature that spaced learning can lead to cost savings {Baylor Scott & White Surgical Hospital–Fort Worth, Resuscitation Quality Improvement 2018}.
- Participation in spaced learning requires ongoing motivation. It may be challenging to engage providers in repeated, effortful practice.
Knowledge Gaps
- There were no studies examining spaced learning in adult advanced life support
- There was a lack of data on the impact of spaced learning on quality of performance in actual resuscitations
- There was a lack of data on impact of spaced learning on patient survival with favourable neurological outcome. In neonates, there was limited data on infant mortality at 24 hours post-delivery. There is currently no data on survival to hospital discharge or long term survival in neonates.
- There was insufficient data to examine the effectiveness of spaced learning on skill acquisition compared to maintaining skill performance and or preventing skill decay.
- There was insufficient data to examine the effectiveness of spaced learning on laypeople compared to healthcare providers.
- There was limited data on impact of spaced learning on human factors (team behaviors and non-technical skills)
- No evidence on cost effectiveness and resource implications of spaced learning.
- There is a need to understand how to address high attrition rates in spaced learning. In order for spaced learning to be effective, we will need to learners’ motivation and reduce their burden.
Attachments
Evidence-to-Decision Table: EIT 1601 Spaced Learning
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