Effects of Implementing Exercise Interventions in School Physical Education on Anxiety Symptoms: A Randomized Clinical Trial

ERCT Criteria Breakdown

• Level 1 Criteria

  • C

    Class-level RCT

    • Classes (not individual students within a class) were used as the randomization unit, meeting the class-level RCT criterion.
    • We performed the randomization considering the classes as sampling units.
    • Relevant Quotes: 1) "We performed the randomization considering the classes as sampling units." (p. 2) 2) "Teachers who agreed to participate were notified that both they and their classes would be randomly allocated to one of the 4 study groups (IG-1, IG-2, IG-3, or CG)." (p. 2) 3) "From a total of 39 eligible classes (27 at one campus and 12 at the other), 16 were randomly selected." (p. 2) Detailed Analysis: Criterion C requires an RCT with randomization at the class level (or a stronger unit such as schools), to reduce within- classroom contamination when the intervention is delivered in normal instruction settings. The paper explicitly states that randomization was conducted using classes as the sampling unit and that classes (and their teachers) were randomly allocated to study groups. Final sentence: Criterion C is met because the paper clearly documents class-level randomization.
  • E

    Exam-based Assessment

    • Outcomes were measured using a mental-health questionnaire (GAD-7), not standardized exam-based educational assessments.
    • The dependent variable was AS, assessed using the Generalized Anxiety Disorder-7 scale, developed by Spitzer et al25 and validated by Kroenke et al.26
    • Relevant Quotes: 1) "The dependent variable was AS, assessed using the Generalized Anxiety Disorder-7 scale, developed by Spitzer et al25 and validated by Kroenke et al.26" (p. 3) 2) "The Generalized Anxiety Disorder-7 consists of 7 items evaluating how the individual has felt over the past 2 weeks." (p. 3) Detailed Analysis: Criterion E requires standardized exam-based assessment of educational outcomes (e.g., national/state standardized tests), not researcher-selected non-academic instruments. This study assesses anxiety symptoms with the GAD-7, which is a validated mental-health screening scale rather than an academic exam. The paper does not report any standardized educational exam outcomes in any subject area. Final sentence: Criterion E is not met because the outcomes are not measured using standardized educational exams.
  • T

    Term Duration

    • Outcomes were measured about 12 weeks after intervention start, which meets the minimum term-length follow-up requirement.
    • Preintervention assessments were conducted 1 week before the start of the intervention, and postintervention assessments were conducted during the week following the completion of the intervention.
    • Relevant Quotes: 1) "This study was a 4-arm, parallel-group randomized controlled trial conducted between February and July 2023." (p. 2) 2) "The intervention protocols were administered over 12 weeks" (p. 1) 3) "Preintervention assessments were conducted 1 week before the start of the intervention, and postintervention assessments were conducted during the week following the completion of the intervention." (p. 3) Detailed Analysis: Criterion T requires that outcomes are measured at least one academic term after the intervention begins (typically about 3 months or more). The paper states the intervention lasted 12 weeks and that postintervention assessments occurred in the week following completion, which places the post-test roughly 12 weeks after intervention start. Twelve weeks is approximately 3 months and meets the typical minimum threshold for a term-length follow-up used in the ERCT definition. Final sentence: Criterion T is met because outcomes were measured approximately 12 weeks after intervention start.
  • D

    Documented Control Group

    • The control group is described as standard PE and baseline characteristics are reported by group, including the control.
    • Participants in the CG followed the standard PE curriculum as previously planned.
    • Relevant Quotes: 1) "Participants in the CG followed the standard PE curriculum as previously planned." (p. 3) 2) "The study involved 326 students (IG-1 = 94, IG-2 = 56, IG-3 = 91, control group = 85)" (p. 1) 3) "Table 1 Baseline Characteristics of Participants According to the Control and Intervention Groups" (p. 5) Detailed Analysis: Criterion D requires a well-documented control group, including what the control condition received and baseline descriptive information for comparison. The paper explicitly defines the control condition as the standard PE curriculum and provides group sizes plus a baseline characteristics table that includes the control group. Final sentence: Criterion D is met because the control condition and baseline control-group characteristics are explicitly documented.

• Level 2 Criteria

  • S

    School-level RCT

    • Randomization was conducted at the class level within campuses, not by randomly assigning whole campuses (schools/sites).
    • We performed the randomization considering the classes as sampling units.
    • Relevant Quotes: 1) "Participants were students enrolled in integrated technical high school programs at 2 campuses of the Federal Institute of Education, Science, and Technology of Southern Rio Grande do Sul (IFSul), Brazil." (p. 2) 2) "We performed the randomization considering the classes as sampling units." (p. 2) 3) "Eight classes were selected from each campus..." (p. 2) Detailed Analysis: Criterion S requires school-level (site-level) randomization where whole schools/campuses are assigned to conditions. Here, classes within each campus were sampled and randomized, and both campuses contributed classes to the study. Because the unit of randomization is explicitly "classes" rather than campuses (schools/sites), this is not a school-level randomized design. Final sentence: Criterion S is not met because assignment was by classes rather than by whole campuses/schools.
  • I

    Independent Conduct

    • The paper does not clearly document an independent external evaluation team separate from the study team and implementers.
    • Data were collected by a team of evaluators composed of undergraduate and graduate PE students, who completed a 3-hour theoretical and practical training session prior to the assessments.
    • Relevant Quotes: 1) "The students’ PE teachers delivered all intervention activities." (p. 2) 2) "Data were collected by a team of evaluators composed of undergraduate and graduate PE students, who completed a 3-hour theoretical and practical training session prior to the assessments." (p. 3) 3) "For quality control purposes, we held weekly meetings with the teachers who applied the intervention on the 3 IG throughout the entire intervention phase." (p. 3) Detailed Analysis: Criterion I requires that the study be conducted independently from the intervention designers/providers to reduce bias in implementation, measurement, and analysis. The paper states that teachers delivered the interventions, and that data were collected by evaluators described as undergraduate and graduate PE students who were trained for assessments. The paper also describes weekly quality-control meetings between the study team and intervention teachers. While assessor blinding is helpful, the paper does not provide a clear statement that an external, independent evaluation organization (separate institution/agency) conducted the study or led evaluation activities independent of the study team. Final sentence: Criterion I is not met because the paper does not explicitly document independent external conduct of the evaluation.
  • Y

    Year Duration

    • The intervention and outcome measurement covered about 12 weeks, far short of 75% of an academic year.
    • The intervention protocols were administered over 12 weeks.
    • Relevant Quotes: 1) "The intervention protocols were administered over 12 weeks" (p. 1) 2) "Preintervention assessments were conducted 1 week before the start of the intervention, and postintervention assessments were conducted during the week following the completion of the intervention." (p. 3) Detailed Analysis: Criterion Y requires outcomes measured at least 75% of one full academic year after the intervention begins. The paper reports a 12-week intervention and postintervention measurement immediately after completion, which is substantially shorter than an academic year. Final sentence: Criterion Y is not met because follow-up is only about 12 weeks from intervention start.
  • B

    Balanced Control Group

    • Student instructional time appears comparable because activities were inserted within standard PE lessons, and extra supports (training/monitoring) are part of the intervention delivery.
    • The aerobic and resistance exercise intervention was implemented immediately after the warm-up, lasting 15 minutes per session.
    • Relevant Quotes: 1) "The diaphragmatic breathing intervention was implemented during the final 15 minutes of each PE lesson." (p. 2) 2) "The aerobic and resistance exercise intervention was implemented immediately after the warm-up, lasting 15 minutes per session." (p. 2) 3) "Sessions lasted 20 minutes and were conducted during the main part of the PE lesson." (p. 2) 4) "Participants in the CG followed the standard PE curriculum as previously planned." (p. 3) 5) "Prior to implementation, teachers completed a 6-hour training session (3-h theoretical and 3-h practical) focused on the delivery of the intervention protocols during PE classes." (p. 2) 6) "For quality control purposes, we held weekly meetings with the teachers who applied the intervention on the 3 IG throughout the entire intervention phase." (p. 3) Detailed Analysis: Criterion B evaluates whether the intervention adds extra time or resources relative to control in a way that could confound the estimated effect, unless those resources are integral to the intervention being tested. Student time: The intervention components were implemented "during" PE lessons (15 to 20 minutes), indicating substitution within the existing PE period rather than adding extra PE time beyond business-as-usual. The control group continued the standard PE curriculum on the same timetable. Additional resources: Teachers assigned to intervention groups received a 6-hour training session and ongoing implementation monitoring (weekly meetings). These supports are part of the intervention delivery model described in the paper (i.e., how the intervention is implemented in real PE settings) rather than a separate enrichment benefit that increases students' PE dosage beyond the scheduled class time. Final sentence: Criterion B is met because the interventions replace portions of standard PE time (not add time) and the additional implementation supports are integral to delivering the intervention package being tested.

• Level 3 Criteria

  • R

    Reproduced

    • No independent replication of this specific trial was found in the paper or via targeted literature searching.
    • there remains a scarcity of interventions comparing the effects of these types of exercises on AS among adolescents during school PE classes
    • Relevant Quotes: 1) "there remains a scarcity of interventions comparing the effects of these types of exercises on AS among adolescents during school PE classes..." (p. 1) Detailed Analysis: Criterion R requires evidence that the specific intervention package and study claim have been independently replicated by a different research team in a different context and published in a peer-reviewed outlet. The paper frames the literature as scarce for comparable school PE interventions on anxiety symptoms, and it does not report that this trial is a replication of a prior trial nor cite an independent replication of this specific 4-arm, class-randomized package conducted in these Brazilian campuses. Targeted literature searching did not identify a peer-reviewed independent replication of this exact trial as of the ERCT check date. Final sentence: Criterion R is not met because independent replication of this specific trial was not identified.
  • A

    All-subject Exams

    • Criterion E is not met, so the all-subject standardized exam requirement cannot be met.
    • Relevant Quotes: 1) "The dependent variable was AS, assessed using the Generalized Anxiety Disorder-7 scale..." (p. 3) Detailed Analysis: Criterion A requires standardized exam-based assessment across all main school subjects, and it cannot be met if criterion E is not met. This study reports anxiety symptoms measured by GAD-7 and does not report standardized academic exams in any subject. Final sentence: Criterion A is not met because standardized academic exams are not used and criterion E is not met.
  • G

    Graduation Tracking

    • The paper reports no post-intervention follow-up, and criterion Y is not met, so graduation tracking cannot be met.
    • Another limitation was the lack of follow-up for participants after the intervention, which prevented us from understanding the possible long-term effects.
    • Relevant Quotes: 1) "Another limitation was the lack of follow-up for participants after the intervention, which prevented us from understanding the possible long-term effects." (p. 7) Detailed Analysis: Criterion G requires tracking participants until graduation. This paper explicitly states there was no follow-up after the intervention, which directly contradicts graduation tracking. Additionally, ERCT requires that if criterion Y (year duration) is not met, criterion G cannot be met under the dependency rule. Targeted searching did not identify a published follow-up paper by these authors tracking this cohort to graduation. Final sentence: Criterion G is not met because the study reports no long-term follow-up and does not track students to graduation.
  • P

    Pre-Registered

    • The trial is reported as registered (NCT05561192) and registry information indicates posting occurred before the study start.
    • The study was reported in accordance with the Consolidated Standards of Reporting Trials16 guidelines for randomized parallel-group trials and was registered at ClinicalTrials.gov (NCT05561192).
    • Relevant Quotes: 1) "The study was reported in accordance with the Consolidated Standards of Report- ing Trials16 guidelines for randomized parallel-group trials and was registered at ClinicalTrials.gov (NCT05561192)." (p. 2) 2) "This study was a 4-arm, parallel-group randomized controlled trial conducted between February and July 2023." (p. 2) 3) "Effects of inserting exercises during physical education classes on anxiety and depression symptoms in adolescents. https://clinicaltrials.gov/show/NCT05561192 (first posted 30 September 2022)." (registry listing as reported in an indexed source) 4) "Study Start date: February 01, 2023" (trial listing) Detailed Analysis: Criterion P requires a publicly available pre-registered protocol before the study begins. The paper provides a ClinicalTrials.gov identifier (NCT05561192). Registry-linked sources report that the record was first posted on 30 September 2022 and that the study start date is 1 February 2023, which places registration before study start. Final sentence: Criterion P is met because the study reports a registry ID and registry-linked dates indicate registration occurred before the study start date.