Effects of a structured fundamental motor skills intervention on executive function in second grade students: a randomized controlled trial

ERCT Criteria Breakdown

• Level 1 Criteria

  • C

    Class-level RCT

    • Treatment was randomised at the individual student level within the same two classes, not at the class or school level, so the class-level criterion is not met.
    • "Using a computer generated random number table, the 100 eligible students were allocated in a 1:1 ratio to either the experimental group (n=50) or the control group (n=50)."
    • Relevant Quotes: 1) "A multistage cluster random sampling method was employed in this study. Firstly, two public primary schools were randomly selected... Subsequently, from all second-grade classes within these two schools, two classes (Class 4, Grade 2 from a school in Panyu District; Class 1, Grade 2 from a school in Zengcheng District) were randomly selected as the research clusters." (p. 2) 2) "Using a computer generated random number table, the 100 eligible students were allocated in a 1:1 ratio to either the experimental group (n=50) or the control group (n=50). The random allocation sequence was generated and kept sealed by an independent researcher not involved in participant recruitment or assessment, ensuring allocation concealment." (p. 2) 3) "All second grade students in the selected classes were invited to participate in the study." (p. 2) Detailed Analysis: Although the paper uses cluster sampling language to select schools and classes, the unit of treatment randomisation was the individual student. The two selected classes were the pool from which students were drawn, and the 100 eligible students within these classes were then individually allocated 1:1 to experimental or control conditions using a random number table. This means students in the same classroom were split between intervention and control, which is student-level randomisation within a class, not class-level or school-level assignment. The ERCT C criterion requires randomisation of entire classes or schools to prevent contamination, unless the intervention is one-to-one tutoring (which this is not; it is a group physical education program). Since treatment and control students co-existed within the same two classes, the design risks contamination and does not satisfy class-level randomisation. Criterion C is not met because the actual treatment allocation was at the individual student level within the same classes, not at the class or school level, and the intervention is not a personal tutoring exception.
  • E

    Exam-based Assessment

    • The study used a child self-report executive function rating scale, not a standardised exam-based assessment, so this criterion is not met.
    • "This scale comprises 36 items rated on a 4-point scale, ranging from 'Never' to 'Always,' scored 1 to 4 respectively. Higher scores indicate poorer executive function."
    • Relevant Quotes: 1) "The Chinese version of the Executive Function Scale was used for assessment before and after the intervention." (Abstract, p. 1) 2) "The Chinese version of the Executive Function Scale, developed by Geurten et al. and revised by Gao et al., was employed to measure the executive function levels of the second-grade primary school students. This scale comprises 36 items rated on a 4-point scale, ranging from 'Never' to 'Always,' scored 1 to 4 respectively. Higher scores indicate poorer executive function." (p. 4) 3) "the assessment of executive function relied entirely on child self-reported behavioral scales... self-report scales assess individuals' generalized perceptions of their behavioral performance in daily contexts. They cannot dissociate specific executive subcomponents as precisely as experimental tasks." (p. 7) Detailed Analysis: The outcome was measured using a self-report questionnaire (the Chinese version of the Executive Function Scale / Questionnaire of Executive Functioning), a 36-item child self-rating scale, not a standardised academic exam. The ERCT E criterion requires a standardised, widely recognised exam-based assessment of educational outcomes (e.g., national or state-wide achievement tests). A psychometric self-report behavioural rating scale is not an exam-based academic assessment; it captures perceptions of behaviour rather than tested academic achievement. The authors themselves acknowledge it is a child self-report scale with limited precision. Therefore this is not a standardised exam-based assessment of an academic subject. Criterion E is not met because outcomes were measured with a self-report behavioural rating scale rather than a standardised exam-based assessment.
  • T

    Term Duration

    • The 10-week intervention with immediate post-test only is shorter than one full academic term, so the term duration criterion is not met.
    • "this study measured only the immediate post-intervention effects, lacking long-term follow-up assessments."
    • Relevant Quotes: 1) "Between September and November 2023, a randomized controlled trial was conducted." (Abstract, p. 1) 2) "In addition to maintaining their regular school physical activities, the experimental group received a 10-week, structured fundamental motor skills intervention. This intervention consisted of three 40-minute sessions per week." (p. 3) 3) "The Chinese version of the Executive Function Scale was used for assessment before and after the intervention." (Abstract, p. 1) 4) "this study measured only the immediate post-intervention effects, lacking long-term follow-up assessments." (p. 7) Detailed Analysis: The intervention ran for 10 weeks (September to November 2023), and the outcome was measured immediately at the end of this 10-week period (a pretest-posttest design). One full academic term is typically defined as approximately 3-4 months. Ten weeks is roughly 2.5 months, which is shorter than a full term, and the authors explicitly state they measured only immediate post-intervention effects with no longer follow-up. The interval from intervention start to outcome measurement is therefore under one full academic term. Criterion T is not met because the interval from intervention start to outcome measurement was only about 10 weeks, shorter than one full academic term, with no longer-term tracking.
  • D

    Documented Control Group

    • The control group's size, baseline characteristics, and conditions are clearly documented, so this criterion is met.
    • "The control group maintained their original regular physical activities during this period. The content, frequency, and intensity of these activities for the control group were identical to the regular activities maintained by the experimental group, but did not include any of the structured fundamental motor skill training designed for this study."
    • Relevant Quotes: 1) "Eighty-nine second grade students were assigned to either an experimental group (n=44) or a control group (n=45)." (Abstract, p. 1) 2) "The control group maintained their original regular physical activities during this period. The content, frequency, and intensity of these activities for the control group were identical to the regular activities maintained by the experimental group, but did not include any of the structured fundamental motor skill training designed for this study." (p. 3) 3) "Independent samples t-tests were used to compare baseline differences between the two groups in terms of age, physical fitness level, and pretest scores of executive function. The chi-square test was used to compare the gender composition between the two groups. This was done to confirm the comparability of baseline characteristics between the groups after randomization." (p. 4) 4) Table 1 reports pretest (Pre CG) and posttest (Post CG) means and standard deviations for the control group across all executive function subscales. (p. 5) Detailed Analysis: The control group is documented in detail. Its size is stated (n=45 analyzed, originally 50). Its condition is described: control students maintained their regular physical activities, identical in content, frequency, and intensity to the regular activities of the experimental group but without the structured FMS training. Baseline characteristics (age, physical fitness, gender composition, and pretest executive function scores) were compared between groups to confirm comparability, and Table 1 reports the control group's baseline and post-intervention scores. This provides demographic/baseline information, group size, and the conditions the control group experienced. Criterion D is met because the control group's size, baseline characteristics, and the conditions it received are clearly documented.

• Level 2 Criteria

  • S

    School-level RCT

    • Schools were not the unit of treatment assignment; students were individually randomised, so the school-level RCT criterion is not met.
    • "Using a computer generated random number table, the 100 eligible students were allocated in a 1:1 ratio to either the experimental group (n=50) or the control group (n=50)."
    • Relevant Quotes: 1) "Firstly, two public primary schools were randomly selected from all such schools in Panyu District and Zengcheng District of Guangzhou City... Subsequently, from all second-grade classes within these two schools, two classes... were randomly selected as the research clusters." (p. 2) 2) "Using a computer generated random number table, the 100 eligible students were allocated in a 1:1 ratio to either the experimental group (n=50) or the control group (n=50)." (p. 2) Detailed Analysis: The S criterion requires randomisation of entire schools (or equivalent implementing units) to treatment vs control. Here, although two schools were randomly selected for participation, the treatment vs control assignment was not done at the school level. Instead, individual students within two classes were randomly allocated to experimental and control conditions. Both schools contributed students to both arms; schools were not assigned as units to intervention or control. Therefore the randomisation unit for treatment allocation was the student, not the school. Criterion S is not met because schools were not randomly assigned to intervention versus control; the treatment allocation occurred at the individual student level.
  • I

    Independent Conduct

    • The same team designed, implemented, and analyzed the intervention with no independent external evaluator, so this criterion is not met.
    • "C.C. and W.Z. designed the study and written the original manuscript. X.G. revised the manuscript. X.Y. collected and analyzed the data."
    • Relevant Quotes: 1) "The intervention protocol was developed by the research team based on the 'Compulsory Education Physical Education and Health Curriculum Standards (2022 Edition)' and by referencing established protocols from domestic and international sources." (p. 3) 2) "The intervention was implemented by four research staff (two experienced physical education teachers and two uniformly trained graduate students in physical education) to ensure standardization and consistency." (p. 3) 3) "C.C. and W.Z. designed the study and written the original manuscript. X.G. revised the manuscript. X.Y. collected and analyzed the data." (Author contributions, p. 9) 4) "the teachers responsible for pre- and post-test data collection were unaware of the students' group assignments." (p. 3) Detailed Analysis: The I criterion requires that the evaluation be conducted independently from those who designed the intervention, to reduce bias. In this study the same research team designed the FMS intervention protocol, implemented it (via their own research staff), and collected and analyzed the data (author X.Y. collected and analyzed the data; the authors designed the study). While outcome assessors were blinded to group assignment to limit Hawthorne effects, there is no independent third-party evaluator: the intervention designers, implementers, and data analysts belong to the same team. Blinding of assessors is a bias control but does not constitute independent conduct by an external evaluation body. Criterion I is not met because the same research team designed, delivered, and analyzed the intervention, with no independent third-party evaluator.
  • Y

    Year Duration

    • The roughly 10-week duration is far short of a full academic year and criterion T is unmet, so the year duration criterion is not met.
    • "this study measured only the immediate post-intervention effects, lacking long-term follow-up assessments."
    • Relevant Quotes: 1) "In addition to maintaining their regular school physical activities, the experimental group received a 10-week, structured fundamental motor skills intervention." (p. 3) 2) "Between September and November 2023, a randomized controlled trial was conducted." (Abstract, p. 1) 3) "this study measured only the immediate post-intervention effects, lacking long-term follow-up assessments." (p. 7) Detailed Analysis: The Y criterion requires outcomes to be measured at least 75% of a full academic year (~9-10 months) after the intervention begins. This study's intervention lasted only 10 weeks with immediate post-test, far short of a full academic year. Additionally, per the criterion-specific instruction, if criterion T (Term Duration) is not met then Y cannot be met, and T is not met here. Criterion Y is not met because the tracking interval was only about 10 weeks, far short of a full academic year, and criterion T was not met.
  • B

    Balanced Control Group

    • The extra structured FMS time is the explicit treatment variable being tested against a business-as-usual control, so the criterion is met.
    • "In addition to maintaining their regular school physical activities, the experimental group received a 10-week, structured fundamental motor skills intervention. This intervention consisted of three 40-minute sessions per week."
    • Relevant Quotes: 1) "In addition to maintaining their regular school physical activities, the experimental group received a 10-week, structured fundamental motor skills intervention. This intervention consisted of three 40-minute sessions per week." (p. 3) 2) "The control group maintained their original regular physical activities during this period. The content, frequency, and intensity of these activities for the control group were identical to the regular activities maintained by the experimental group, but did not include any of the structured fundamental motor skill training designed for this study." (p. 3) Detailed Analysis: Following the Criterion B decision tree: the experimental group received additional resources/time, namely three extra 40-minute structured FMS sessions per week for 10 weeks, on top of their regular physical activities. The control group received only their regular physical activities and did not receive these extra structured sessions, so the control group did not receive matching additional time. The next question is whether these additional resources ARE the treatment variable being tested. The explicit purpose of the study is to examine the effectiveness of the structured FMS intervention itself: "this study aimed to examine the effectiveness of a 10-week structured fundamental motor skills intervention on the executive function." The added structured FMS sessions ARE the intervention being tested against a business-as-usual baseline (the control's regular physical activities). The extra time and structured content are integral to the treatment being evaluated, not a separable confounding add-on. Under the standard, when the additional resource is the explicit treatment variable, the control may remain at the business-as-usual level by design, and Criterion B is met. Criterion B is met because the additional structured FMS sessions are the explicit treatment variable under investigation, and the control group appropriately received the business-as-usual level of regular physical activity.

• Level 3 Criteria

  • R

    Reproduced

    • No independent replication of this specific FMS trial by a different research team exists, so this criterion is not met.
    • Relevant Quotes: 1) "Given the relative scarcity of randomized controlled trial evidence regarding systematic fundamental motor skills interventions for lower primary school students, this study aimed to examine the effectiveness of a 10-week structured fundamental motor skills intervention." (Abstract, p. 1) 2) "empirical research examining the impact of systematic, standard-based FMS interventions on executive function in lower primary school grades remains relatively scarce." (p. 2) Detailed Analysis: The R criterion requires that this specific study be independently replicated by a different research team in a different context, published in a peer-reviewed journal. This is a newly published 2026 study (received November 2025, accepted March 2026) that the authors themselves frame as addressing a scarcity of evidence; there is no mention of any independent replication of this particular FMS-on-executive-function trial. Internet searching was conducted across Nature, PubMed, and general web sources; while related motor-intervention studies exist (e.g., Hudson et al. 2021, Kashfi et al. 2019, Westendorp et al. 2014, and FMS-EF meta-analyses in preschoolers), these are separate studies of different programs, age groups, and populations, not replications of this specific Guangzhou second-grade FMS protocol. No independent reproduction of this specific study by a different research team was identified. Criterion R is not met because there is no independent replication of this specific study by a different research team in a peer-reviewed journal.
  • A

    All-subject Exams

    • Criterion E is unmet and only executive function (not all main subjects via standardised exams) was assessed, so this criterion is not met.
    • "The Chinese version of the Executive Function Scale was used for assessment before and after the intervention."
    • Relevant Quotes: 1) "The Chinese version of the Executive Function Scale was used for assessment before and after the intervention." (Abstract, p. 1) 2) "the assessment of executive function relied entirely on child self-reported behavioral scales." (p. 7) Detailed Analysis: The A criterion requires measuring impact on all main school subjects using standardised exam-based assessments, and it explicitly depends on criterion E being met. Here criterion E is not met (the outcome was a self-report executive function scale, not a standardised academic exam). Furthermore, the study measured only executive function (a single cognitive construct), not performance across the main academic subjects such as mathematics, reading, or science. Both because E is unmet and because only one cognitive domain was assessed, this criterion fails. Criterion A is not met because criterion E is not met and the study assessed only executive function rather than all main subjects via standardised exams.
  • G

    Graduation Tracking

    • The study had no long-term follow-up or graduation tracking and criterion Y is unmet, so this criterion is not met.
    • "this study measured only the immediate post-intervention effects, lacking long-term follow-up assessments."
    • Relevant Quotes: 1) "this study measured only the immediate post-intervention effects, lacking long-term follow-up assessments. Therefore, it remains undetermined whether the observed promotive effects are transient or can have a lasting positive impact." (p. 7) 2) "setting up follow-up points months or even longer after the intervention ends would allow for the evaluation of the long-term benefits." (p. 8) Detailed Analysis: The G criterion requires tracking participants until their graduation from the educational stage. This study explicitly measured only immediate post-intervention outcomes with no long-term follow-up at all, let alone tracking second-grade students through to graduation. Internet searching for subsequent publications by the same authors (Cheng Chen, Xiang Gao, Xuyan Cui, Wenjuan Zhang) tracking this Guangzhou second-grade cohort to graduation found no such follow-up paper. Additionally, per the criterion-specific instruction, if criterion Y is not met then G cannot be met, and Y is not met here. Criterion G is not met because the study collected only immediate post-intervention data with no graduation tracking, no follow-up publication was found, and criterion Y is unmet.
  • P

    Pre-Registered

    • The paper reports ethics approval but no public trial registry pre-registration, so this criterion is not met.
    • "The study protocol... was submitted to and approved by the Ethics Committee of Guangzhou Sport University (Approval No.: 2023LCLL-12)."
    • Relevant Quotes: 1) "The study protocol, which included the research procedures, intervention content, informed consent forms, measurement tools, and data confidentiality measures, was submitted to and approved by the Ethics Committee of Guangzhou Sport University (Approval No.: 2023LCLL-12)." (p. 3) 2) "This study strictly adhered to the ethical principles outlined in the Declaration of Helsinki." (p. 3) Detailed Analysis: The P criterion requires that the full study protocol (hypotheses, methods, planned analyses) be pre-registered on a public trial registry (e.g., ClinicalTrials.gov, ISRCTN, ChiCTR, OSF) before data collection begins. This paper describes ethics committee approval of the protocol, but ethics approval is not the same as public pre-registration of a trial protocol. There is no mention of a public trial registry, registration ID, or pre-registration date anywhere in the paper. Internet checking of the published Nature article and registry searches found no associated public trial registration. Therefore there is no evidence of a pre-registered protocol. Criterion P is not met because the paper reports only ethics committee approval and provides no public trial registry pre-registration link, ID, or date.