Investigating the effect of Manitoba's province-wide physical education policy on secondary school students' physical activity: a natural experiment
Source: My personal notes from Public Health Ontario events presentation 2017-09-12
In fall 2008, Manitoba implemented a province-wide policy requiring a physical education (PE) credit for students in grades 11 and 12, the first of its kind in Canada. The PE curriculum requires grades 11 and 12 students to complete a minimum of 55 hours (50% of course hours) of moderate to vigorous physical activity during the school semester to achieve the course credit. The study being discussed during this session examines the impact of this PE policy on secondary school students’ moderate to vigorous physical activity as a large natural experiment. Findings can provide evidence about policy features that may improve the PE policy in Manitoba and inform future PE policies in other jurisdictions.
Presenter: Dr. Erin Hobin
Dr. Erin Hobin (PhD) is a Scientist in Heath Promotion, Chronic Disease and Injury Prevention at Public Health Ontario with a status-only appointment at the University of Toronto and University of Waterloo. Her research focuses on developing and evaluating population level interventions for chronic disease prevention, specifically in the areas of healthy weights, healthy eating, physical activity, and alcohol control.
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92% of youth are not meeting Canadian recommendations for activity (60 mins per day)
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Girls slightly more inactive than boys. Adolescents slightly more inactive compared to younger children.
Multiple factors affecting physical activity
Section titled “Multiple factors affecting physical activity”Individual and external
- Schools and their policies are critical, affecting many factors of public health (obesity, smoking)
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Multi-component interventions
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PE class, community-home links, flexible delivery
- Task force report, meeting around Manitoba with people for recommendations
Result: Policy changes-PE classes
Section titled “Result: Policy changes-PE classes”Grade 9 to 12 classes
- Three components, in class, flexible, and physical
- In and out of classroom percentage implementation
Choices of schedules
Section titled “Choices of schedules”
Out of Classroom direction and supports
Section titled “Out of Classroom direction and supports”
Policy Evaluation
Section titled “Policy Evaluation”
moderate- to-vigorous physical activity (MVPA)
Policy Impact
Section titled “Policy Impact”
Study 1 - PEI is comparison
Study 2 - before/after and Alberta for comparison
- some surveys were part of larger surveillance data
Check vigorous and moderate physical activity, duration, and weekly times
In adjusted model, no significant differences between intervention and comparison
Study 2
Section titled “Study 2”
1 classroom per school was selected.
25% people excluded due to incorrect data or unreturned accelerometers
Challenge in follow ups as children moved around and PE classes they were in may have changed.
School SES = socioeconomic status
Note at t=0, high variability
T=1,2,3 movement all over
T=0 to 6, see trajectory is going down. I.e. less time in MVPA
In adjusted model, no significant differences between intervention and comparison
Outcomes
Section titled “Outcomes”
Study result:
- Data for future use
- PE policies are still relevant despite this one did not significantly affect results
- It was a natural experiment, so actual implementation was dependent on schools which could affect results
Note drop at 60mins
Ability of schools to satisfy policies
Section titled “Ability of schools to satisfy policies”CONTRIBUTION TO THE EVIDENCE BASE
- PE policy did not significantly improve students’ MVPA
POSSIBLE EXPLANATION
- Issues with implementation across schools
POSSIBLE AMENDMENT
- Assessing intervention fidelity and reach, as well as various delivery models applied by schools
Study Strength
Section titled “Study Strength”- Natural experiment and quasi-experimental design
- Uses cross-sectional census survey data and objective measures of MVPA
- Parallel data from comparison provinces that did not enact a PE policy
- Includes follow-up data over a 4-year period
Limitations
Section titled “Limitations”- Baseline differences between comparison and intervention samples on key characteristics known to associate with MVPA, such as sex, age, SES
- Some schools in comparison and intervention conditions did not participate in the survey data collections in Study 1 at baseline and follow-up
- No data identifying if student was enrolled in PE in the semester of follow-up data collections in Studies 1 or 2
Presentation Summary
Section titled “Presentation Summary”- First study to examine the effect of a province-wide secondary school PE policy on student MVPA
- PE policy did not significantly improve students’ MVPA
- Provides evidence to inform current and future secondary school PE policies as well as future natural experimental studies of PE policies
- Conducting similar evaluations of large-scale PE interventions or policies in different settings would be valuable and further contribute to converging knowledge
Questions
Section titled “Questions”Is the policy implemented too late in life?
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MVPA declines on school entry and continues to decline in schooling
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Interventions should be done at school entry, through to adolescence+
Was ethnicity tracked?
- No - though would be interesting
What is “out” time?
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Not supervised by a teacher. It is signed by an adult so similar to a volunteer hours tracking.
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At 9-10 grades, feedback and out time was genuinely needed due to out of school activity
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Policy is specific in MVPA. Students were taught what it was, though it was student self reported.
What about early starts at school?
- Students are not randomized to conditions, so it was not possible to link ineffective results with conditions. It is possible things like busing affect physical activity (PA)
Any qualitative data?
- Barriers data
How could policy be made effective?
- Use study data to understand our current state and how to improve.
- Increase amount of time mandated in policy
- Increase in school PE credit
- Extend PE class to full year