The Impact of Healthy Harlem on the Body Mass Index and Weight Status of Adolescents after Two and Three Years

Publisher: Princeton, NJ: Mathematica Policy Research
Mar 15, 2018
Martha Bleeker, James Mabli, Mary Kay Fox, Betina Jean-Louis, and Marlene Fox

Key Findings:

  • Students who were overweight or obese and participated in Get Fit and Prevention had significantly lower BMI z-scores two and three years later. These changes were concentrated among boys.
  • The percentage of students who were overweight or obese after two and three years of participation was significantly lower than at baseline.
  • The percentage of students who were obese after two and three years was also significantly lower than at baseline, although these changes were smaller and concentrated among boys.

For overweight and obese middle and high school students enrolled in Harlem Children’s Zone (HCZ) after-school programs, participation in Healthy Harlem led to sustained positive impacts on body mass index (BMI) and weight status, according to interim findings from Mathematica. To assess Healthy Harlem’s effectiveness, researchers monitored students during an initial baseline year and then measured program impacts after two and three years of participation. As described in this issue brief, the findings reveal that participation in Healthy Harlem’s Get Fit and Prevention components resulted in lower BMI z-scores and a reduction in the percentage of students who were overweight or obese.


Evaluation of the Harlem Children's Zone Healthy Harlem Initiative


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James Mabli
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Martha Bleeker
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Mary Kay Fox
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