Effect of low-dose, high-frequency advanced life support training versus annual full-day training on simulation-based resuscitation performance: a randomized controlled trial

ERCT Criteria Breakdown

• Level 1 Criteria

  • C

    Class-level RCT

    • Randomisation was performed at the individual participant level rather than by class or school.
    • "Participants were assigned identification numbers in order of enrollment, and simple randomization with a 1:1 allocation ratio was applied." (p. 6)
    • Relevant Quotes: 1) "In this randomized, controlled, simulation-based trial, 35 emergency medical services (EMS) professionals were allocated to either low-dose, high-frequency ALS training (intervention group, n = 18) or a single annual full-day ALS training (control group, n = 17)." (Abstract, p. 1) 2) "A random allocation sequence was generated using IBM SPSS Statistics (IBM Corp., Armonk, NY, USA). Participants were assigned identification numbers in order of enrollment, and simple randomization with a 1:1 allocation ratio was applied." (p. 6) 3) "Each scenario was conducted by a team of two emergency medical service personnel representing the participating emergency medical team; the focus of the evaluation was on the team leader." (p. 4) Detailed Analysis: Criterion C requires randomisation at the class level or stronger (school level), unless the intervention is a personal/one-to-one tutoring format. In this trial the unit of randomisation was the individual EMS professional: 35 participants were assigned identification numbers and allocated 1:1 by simple randomisation. There is no mention of classes, cohorts, sites, or institutions being the unit of randomisation. The intervention (team-based ALS simulation training in teams of two) is not a one-to-one personal tutoring intervention, so the tutoring exception does not apply. Because randomisation was performed at the individual participant level rather than at the class or school level, contamination between individuals cannot be excluded. Criterion C is not met because randomisation was conducted at the individual participant level, not at the class or school level, and no tutoring exception applies.
  • E

    Exam-based Assessment

    • The study used a self-developed, non-standardised rating instrument rather than a recognised standardised exam.
    • "it was decided to develop a new rating instrument rather than adapting or directly mapping existing tools." (p. 5)
    • Relevant Quotes: 1) "A self-developed rating instrument was used to assess resuscitation quality during training sessions and to compare across different periods." (p. 2) 2) "Given these conceptual differences and the lack of a comprehensive instrument tailored to this project's specific objectives, it was decided to develop a new rating instrument rather than adapting or directly mapping existing tools. Consequently, no formal alignment with previously published rating instruments was pursued." (p. 5) 3) "Performance was assessed at baseline and after 12 months using a validated 29-item rating instrument, with each item rated on a 5-point Likert scale (1 = poor performance, 5 = excellent performance)." (p. 4) 4) "Although the self-developed rating instrument has been validated, it is not yet internationally established." (p. 11) Detailed Analysis: Criterion E requires the use of a standardised, widely recognised exam-based assessment that was not specially designed for the study. Here the outcome was measured with a rating instrument that the authors explicitly developed themselves for this project, deciding "to develop a new rating instrument rather than adapting or directly mapping existing tools." Although the instrument was internally validated for reliability (Cronbach's alpha 0.793; ICC 0.794), the authors state it "is not yet internationally established." This is a custom, study-specific instrument rather than a standardised, widely recognised exam. Criterion E is not met because the outcome was measured with a self-developed, non-standardised rating instrument created specifically for this study.
  • T

    Term Duration

    • Outcomes were measured 12 months after the intervention began, well beyond one full term.
    • "Performance was assessed at baseline and after 12 months using a validated 29-item rating instrument." (Abstract, p. 1)
    • Relevant Quotes: 1) "Performance was assessed at baseline and after 12 months using a validated 29-item rating instrument." (Abstract, p. 1) 2) "Subsequently, the intervention group received CPR training every 4 weeks ... The training session lasted about 10 to 15 min." (p. 2) 3) "Short scenario resuscitation training over 1 year, every four weeks" (Fig. 1, p. 3) 4) "In comparison with the initial measurement (t0), the measurement following one year (t1) exhibited an enhancement of the overall mean performance score." (p. 6-7) Detailed Analysis: Criterion T requires that outcomes be measured at least one full academic term (approximately 3-4 months) after the intervention begins. In this trial the baseline assessment (t0) occurred at study entry and the primary outcome was measured 12 months later (t1), with the intervention group trained repeatedly over that one-year period. The interval from intervention start to primary outcome measurement is therefore 12 months, which far exceeds one full term. Because the year-long tracking is satisfied, the weaker term-duration requirement is also satisfied. Criterion T is met because outcomes were measured 12 months after the intervention began, far exceeding one full academic term.
  • D

    Documented Control Group

    • The control group's demographics, baseline scores, and training received are clearly documented in the text and Tables 1 and 2.
    • "The control group received one day of training corresponding in scope to the first day of an ERC ALS course ... as outlined by the European Resuscitation Council (ERC)." (p. 4)
    • Relevant Quotes: 1) "A total of 35 subjects participated in the study, 18 in the intervention group and 17 in the control group. Table 1 lists the general and demographic data of the test subjects." (p. 6); "Both groups were comparable at the start of the study and had similar starting conditions." (p. 6) 2) "The control group received one day of training corresponding in scope to the first day of an ERC ALS course (BLS and defibrillation, theoretical introduction to the ALS algorithm, and scenario simulation training with feedback), as outlined by the European Resuscitation Council (ERC)." (p. 4) 3) "For the control group, an initial resuscitation scenario was likewise conducted by a team of two paramedics at the beginning of the training course to establish baseline performance." (p. 3) 4) "Table 1 Demographic characteristics of the participants" reports control-group sex, age, years of professional experience, frequency of prior resuscitation training, and time since last real-life resuscitation (Table 1, p. 6); Table 2 reports the control group's pre and post overall mean score (3.8 to 4.2, Mean +/- SD) (Table 2, p. 7). Detailed Analysis: Criterion D requires that the control group be well-documented, including demographics, baseline performance, and the conditions/treatment it received. The paper provides Table 1 with the control group's sex, age, years of professional experience, frequency of prior resuscitation training, and time since last real-life resuscitation, and Table 2 with the control group's baseline (pre) and post performance scores. The specific treatment received by the control group (a single full-day ERC-style ALS course) is described in detail. This provides adequate documentation of who the control group was, their baseline characteristics, and what they received. Criterion D is met because the control group's demographics, baseline performance, and the training it received are documented in the text and in Tables 1 and 2.

• Level 2 Criteria

  • S

    School-level RCT

    • Randomisation was at the individual level, not at the school or institutional level.
    • "simple randomization with a 1:1 allocation ratio was applied." (p. 6)
    • Relevant Quotes: 1) "Participants were assigned identification numbers in order of enrollment, and simple randomization with a 1:1 allocation ratio was applied." (p. 6) 2) "35 emergency medical services (EMS) professionals were allocated to either low-dose, high-frequency ALS training (intervention group, n = 18) or a single annual full-day ALS training (control group, n = 17)." (Abstract, p. 1) 3) "Recruitment was conducted through direct communication with EMS organizations and snowball sampling via the medical faculty." (p. 2) Detailed Analysis: Criterion S requires randomisation at the school level, i.e. the institution or unit implementing the intervention (school, centre, club, site, etc.). In this trial randomisation was performed at the individual participant level, with 35 EMS professionals recruited across organisations via snowball sampling and allocated 1:1 by simple randomisation. There is no randomisation of schools, sites, EMS stations, or institutions; the unit of allocation was the individual person. Criterion S is not met because randomisation was conducted at the individual level, not at the school or institutional level.
  • I

    Independent Conduct

    • The same author team designed, conducted, and analysed the trial, so conduct was not independent despite blinded outcome raters.
    • "L.M. and D.H. conceptualized the study. L.M., R.R., and D.H. performed the formal analysis ... R.R. and D.H. supervised the project and administered the study." (p. 11)
    • Relevant Quotes: 1) "Authors' contributions: L.M. and D.H. conceptualized the study. L.M., R.R., and D.H. performed the formal analysis. L.M., P.D., and D.H. curated the data and conducted the investigation. R.R. and D.H. supervised the project and administered the study." (p. 11) 2) "A self-developed rating instrument was used to assess resuscitation quality." (p. 2) 3) "The same panel of six independent experts who participated in the development and reliability testing of the rating instrument also performed the primary outcome rating for this trial ... The expert raters were blinded to group allocation." (p. 5) 4) "Six students from the Bachelor of Science in Emergency Medical Services Education program at Technical College Deggendorf, who were not involved in the development of the rating instrument or in the primary rating, independently evaluated all 13 video scenarios using the instrument. Raters were blinded to group allocation." (p. 5) Detailed Analysis: Criterion I requires that the study be conducted independently from the authors who designed the intervention, with a clear statement of third-party or external conduct of data collection and analysis. Here the same author team (L.M., D.H.) conceptualised the study, developed the self-made rating instrument, conducted the investigation, administered the study, and performed the formal analysis. While there are genuine blinding safeguards for outcome scoring (the six primary expert raters were blinded to allocation, and a supplementary blinded rating was done by six independent students who did not develop the instrument), these mitigate measurement bias rather than establish independent conduct of the trial itself. The design, implementation, and statistical analysis were carried out by the intervention's own authors without an external evaluation body. Criterion I is not met because the same team designed, conducted, administered, and analysed the trial; blinded raters reduce scoring bias but do not constitute independent conduct of the study.
  • Y

    Year Duration

    • Outcomes were measured 12 months after the intervention began, covering a full academic year.
    • "This trial compared low-dose, high-frequency ALS training with annual full-day training regarding simulation-based resuscitation performance after one year." (Abstract, p. 1)
    • Relevant Quotes: 1) "This trial compared low-dose, high-frequency ALS training with annual full-day training regarding simulation-based resuscitation performance after one year." (Abstract, p. 1) 2) "Short scenario resuscitation training over 1 year, every four weeks" (Fig. 1, p. 3) 3) "Performance was assessed at baseline and after 12 months using a validated 29-item rating instrument." (Abstract, p. 1) 4) "In comparison with the initial measurement (t0), the measurement following one year (t1) exhibited an enhancement of the overall mean performance score." (p. 6-7) Detailed Analysis: Criterion Y requires that outcomes be measured at least 75% of a full academic year (about 9-10 months) after the intervention begins. In this trial the baseline was taken at study entry (t0) and the primary outcome was measured after 12 months (t1), with the intervention delivered every four weeks across that entire year. A 12-month interval clearly exceeds 75% of an academic year, and because Y is satisfied the weaker term-duration criterion (T) is also satisfied. Criterion Y is met because outcomes were tracked and measured 12 months after the intervention began, covering a full year.
  • B

    Balanced Control Group

    • Both arms received active, standard-adherent ALS training with comparable resources, with training frequency/format itself being the treatment variable.
    • "The intervention consisted of a low-dose, high-frequency training approach (LDHF), compared with standard annual training in the control group. Both training formats adhered to the ALS standard." (p. 2)
    • Relevant Quotes: 1) "The objective of this trial was to compare the effect of low-dose, high-frequency ALS training (monthly short sessions) versus annual full-day training on resuscitation performance." (p. 2) 2) "The intervention consisted of a low-dose, high-frequency training approach (LDHF), compared with standard annual training in the control group. Both training formats adhered to the ALS standard." (p. 2) 3) Intervention: "Participants then received theoretical instruction on current resuscitation guidelines, followed by CPR scenario training in teams of two, totaling approximately 2 h. Subsequently, the intervention group received CPR training every 4 weeks ... The training session lasted about 10 to 15 min." (p. 2) 4) Control: "The control group received one day of training corresponding in scope to the first day of an ERC ALS course (BLS and defibrillation, theoretical introduction to the ALS algorithm, and scenario simulation training with feedback)." (p. 4) Detailed Analysis: Criterion B compares the nature, quantity, and quality of resources (time, budget, materials) given to each condition. This is not a treatment-versus-no-treatment design: both arms are active training conditions that "adhered to the ALS standard." The explicit treatment variable being tested is the training FORMAT and FREQUENCY (distributed low-dose, high-frequency monthly sessions vs. a single massed annual full-day course), not the addition of extra resources to only one arm. On total dosage, the control group received a full training day (roughly eight hours) while the intervention group received about 2 h initial training plus roughly monthly 10-15 min sessions over a year (on the order of 4-5 h total), so the intervention arm did not receive additional time or budget relative to the control; if anything the control received more concentrated instructional time. Both groups used the same manikin, equipment, ERC-qualified instructors, and scenario structure. Under the decision tree, the contrast in scheduling is the explicit treatment variable and the control is a genuine active comparator with comparable (indeed non-inferior) resources, so balance is satisfied. Criterion B is met because both arms received active, standard-adherent ALS training with comparable resources, and the study explicitly tests training frequency/format (distributed vs. massed) as the treatment variable rather than adding unmatched resources to the intervention group.

• Level 3 Criteria

  • R

    Reproduced

    • No independent replication of this specific trial by a separate research team exists.
    • "Whether such low-dose, high-frequency approaches are more effective in the ALS context ... has not yet been adequately addressed." (p. 2)
    • Relevant Quotes: 1) "Previous studies investigating repeated short training sessions, for example, among firefighters, have shown only limited improvements in Basic Life Support (BLS) performance [19]." (p. 2) 2) "Whether such low-dose, high-frequency approaches are more effective in the ALS context - particularly regarding team management and process quality - has not yet been adequately addressed." (p. 2) 3) "Although the self-developed rating instrument has been validated, it is not yet internationally established." (p. 11) Detailed Analysis: Criterion R requires that this specific study be independently replicated by a different research team in a different context and published in a peer-reviewed journal. This is a recent (2026) trial, and the authors state that whether low-dose, high-frequency training is more effective in the ALS context "has not yet been adequately addressed," framing the study as novel. The only related prior work cited is a firefighter BLS study [19], which is a different intervention/context and not a replication of this ALS trial. An external check (DOI landing page and registry) found no independent replication of this specific trial as of the review date; the trial was only registered in 2021 and published in 2026, so an independent reproduction has not had time to appear. Criterion R is not met because there is no independent replication of this specific study by a separate research team.
  • A

    All-subject Exams

    • Criterion E is not met and only a single specialised domain was assessed, so all-subject coverage fails.
    • "The primary endpoint was the overall performance score for resuscitation management, comprising technical, non-technical, and procedural domains." (p. 4)
    • Relevant Quotes: 1) "The primary endpoint was the overall performance score for resuscitation management, comprising technical, non-technical, and procedural domains." (p. 4) 2) "Secondary endpoints included domain-specific performance scores (NTS, defibrillation-related, and cardio-pulmonary resuscitation [CPR] items) ... as well as time to key interventions." (Abstract, p. 1) Detailed Analysis: Criterion A requires that the study measure impact across all main subjects using standardised exam-based assessments, and it explicitly depends on criterion E being met. Here criterion E is not met because the outcome was measured with a self-developed, non-standardised rating instrument. Furthermore, the study assessed only a single, highly specialised domain (resuscitation performance and its sub-domains of NTS, defibrillation, and CPR), not multiple core curriculum subjects. On both grounds the criterion fails. Criterion A is not met because criterion E is not met and the study measured only a single specialised skill domain rather than all main subjects.
  • G

    Graduation Tracking

    • Measurement ended at 12 months with no tracking of participants to any graduation endpoint.
    • "Performance was assessed at baseline and after 12 months using a validated 29-item rating instrument." (Abstract, p. 1)
    • Relevant Quotes: 1) "Performance was assessed at baseline and after 12 months using a validated 29-item rating instrument." (Abstract, p. 1) 2) "Eligible participants were active, full-time EMS personnel with appropriate qualifications as paramedics (4600 h of training) or emergency medical technicians (520 h of training)." (p. 2) 3) "Multicenter studies with patient-centered outcomes and health-economic analyses are warranted." (p. 11) Detailed Analysis: Criterion G requires follow-up tracking of participants through to graduation from their educational stage, and it depends on criterion Y being met. Although Y is met here, the participants are already-qualified working EMS professionals rather than students progressing to a graduation milestone, and outcome measurement stopped at the 12-month follow-up (t1). No tracking to any graduation endpoint or longer-term follow-up is described, and no follow-up publication tracking this cohort to graduation was identified. Criterion G is not met because the study measured outcomes only up to 12 months with no tracking to graduation.
  • P

    Pre-Registered

    • The trial was prospectively registered (DRKS00024822, 26 March 2021) before enrolment began (1 April 2021), confirmed against the DRKS registry record.
    • "The study was prospectively registered in the German Register of Clinical Studies (DRKS00024822)." (p. 11)
    • Relevant Quotes: 1) "The trial was registered on March 26, 2021, in the German Registry of Clinical Trials under ID DRKS00024822 https://trialsearch.who.int/." (p. 2) 2) "The study was prospectively registered in the German Register of Clinical Studies (DRKS00024822)." (p. 11) 3) "Ethical approval was obtained from the Ethics Committee of the Medical Faculty at the Eberhard Karls University Tübingen (reference number 681/2020BO2)." (p. 11) Detailed Analysis: Criterion P requires the study protocol to be pre-registered before data collection begins, with a registry reference and timing. The paper reports a specific registry (German Register of Clinical Studies, a WHO primary registry accessible via ICTRP) with the trial ID DRKS00024822 and a registration date of March 26, 2021, and it explicitly states the study was "prospectively registered." The DRKS registry entry for DRKS00024822 was checked directly and confirms this: the registration is listed as type "Prospective," dated 26 March 2021, with the first enrolment/recruitment start recorded as 1 April 2021. Registration (26 March 2021) therefore precedes the start of enrolment (1 April 2021), and ethics approval (reference 681/2020BO2, 2020) predates registration, consistent with a genuine pre-data-collection timeline. Criterion P is met because the trial was prospectively registered in a recognised clinical-trials registry (DRKS00024822) on 26 March 2021, before enrolment began on 1 April 2021, as confirmed against the DRKS registry record.