If there had been no physical education program in the Cambridge Public School system previously, would the outcomes be considered bounded or unbounded?

CASE DESCRIPTION

The Cambridge Public School system was awarded a three-year grant to implement a physical activity intervention. The intervention consisted of three components: a policy change requiring all students in grades K-12 to be enrolled in physical education (PE) class, PE teachers devising ways to increase active minutes of PE class, and free before- and after-school physical activity programs.

The primary objectives of this intervention were as follows:

PROCESS

• Within one month of program implementation, 99% of the student body will be enrolled in PE class.
• Within one month of program implementation, the PE staff will have devised and implemented a curriculum that will increase active minutes spent in PE class.
• After one year of implementation, enrollment in before- and after-school activities will have doubled.
• After two years of implementation, enrollment in before- and after-school activities will have increased by another 25% from year two.
• After three years of implementation, 90% of the student body will be enrolled in before- and/or after-school activities.
• After one year of implementation, the number of combined active minutes that students spend in PE class and in before- and after-school activities will double.
• After two years of implementation, the number of combined active minutes that students spend in PE class and in before- and after-school activities will remain at doubled the baseline minutes from year one.
• At the end of three years of implementation, the number of combined active minutes that students spend in PE class and in before- and after-school activities will increase by another 25% from year two.

OUTCOME

• After one year of implementation, the average number of steps that students take in PE class and in before- and after-school activities will increase by 1000, as measured by a pedometer.
• After two years of implementation, the average number of steps (walking) that students take in PE class and in before- and after-school activities will remain at 1000 steps plus baseline, as measured by a pedometer.
• After three years of implementation, the average number of steps that students take in PE class and in before- and after-school activities will increase an additional 500 steps compared to the end of year two, as measured by a pedometer.

IMPACT

• After three years of implementation, the number of at risk of overweight and overweight students will decrease by 5%, as measured by body mass index (BMI).

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