Effective nationwide school-based participatory extramural program on adolescent body mass index, health knowledge and behaviors.
BACKGROUND
Adolescent obesity is a major public health concern. Open to all high school students regardless of weight status, HealthCorps is a nationwide program offering a comprehensive high school-based participatory educational program to indirectly address obesity. We tested a hypothesis that the HealthCorps program would decrease BMI z-scores among overweight or obese students, and reduce obesity rates, and evaluated its effects on health knowledge and behaviors.


METHODS
HealthCorps aimed to improve student knowledge and behaviors regarding nutrition quality, physical activity, sleep, breakfast intake, and mental resilience. Participating students received through HealthCorps coordinators weekly or bi-weekly classroom lessons either for a semester or a year in addition to various during- and after-school health-promoting activities and mentorship. Self-reported height and weight were collected along with questionnaires assessing knowledge and behaviors during 2013-2014 academic year among 14 HealthCorps-participating New York City high schools. This quasi experimental two-arm pre-post trial included 611 HealthCorps and 221 comparison arm students for the analytic sample. Sex-specific analyses stratified by weight status were adjusted for age and Hispanic ethnicity with clustering effects of schools and students taken into account.


RESULTS
HealthCorps female overweight/obese and obese student had a significant decrease in BMI z-scores (post-pre delta BMI z-score = -0.16 (95%CI = (-0.26, -0.05), p = 0.004 for the former; and = -0.23 (-0.44, -0.03), p = 0.028, for the latter) whereas comparison female counterparts did not. The HealthCorps students, but not the comparison students, had a significant increase for all knowledge domains except for the breakfast realm, and reported a greater number of significant behavior changes including fruit and vegetable intake and physical activities.


CONCLUSIONS
The HealthCorps program was associated with reduced BMI z-score in overweight/obese and obese female adolescents, with enhanced health knowledge and behavior for both sexes. With its wide reach, this may be a promising program to help combat adolescent obesity in schools.


TRIAL REGISTRATION
This study is registered as a clinical trial at the ClinicalTrials.gov registry with trial number NCT02277496 on September 10, 2014 (Retrospectively registered).
['Heo|Moonseong|M|http://orcid.org/0000-0001-7711-1209', 'Jimenez|Camille C|CC|', 'Lim|Jean|J|', 'Isasi|Carmen R|CR|', 'Blank|Arthur E|AE|', 'Lounsbury|David W|DW|', 'Fredericks|Lynn|L|', 'Bouchard|Michelle|M|', 'Faith|Myles S|MS|', 'Wylie-Rosett|Judith|J|']
D000293:Adolescent D000294:Adolescent Behavior D015992:Body Mass Index D005260:Female D015438:Health Behavior D007722:Health Knowledge, Attitudes, Practice D006306:Health Surveys D006801:Humans D008297:Male D009519:New York City D017063:Outcome Assessment, Health Care D063766:Pediatric Obesity D015397:Program Evaluation D012572:School Health Services D057566:Self Report
Adolescent obesity High school HealthCorps Health behavior