title: The effects of the Child and Adolescent Trial for Cardiovascular Health upon psychosocial determinants of diet and physical activity behavior.
abstract: BACKGROUND
  The Child and Adolescent Trial for Cardiovascular Health is a multisite study of a school-based intervention to reduce or prevent the development of risk factors for cardiovascular disease. The purpose of this paper is to present the evaluation results of the 3-year intervention, focusing upon the psychosocial variables conceptualized as determinants of dietary and physical activity behaviors.
  
  
  METHODS
  A total of 96 schools across four study sites (California, Louisiana, Minnesota, and Texas) were randomized to two treatment conditions: intervention and control. Pre- and postmeasurements on the health behavior questionnaire were collected from over 6,000 students. The data analyses utilized a nested design approach in which schools served as the primary unit of analysis. Repeated-measures multivariate analyses were applied to investigate effect sizes for each determinant and to explore theoretical relationships among the determinants over time.
  
  
  RESULTS
  The findings indicated sustained significant effects in improved knowledge, intentions, self-efficacy, usual behavior, and perceived social reinforcement for healthy food choices (P < 0.0001 for these five variables) after 3 years. Intermittent effects were observed for perceived support and self-efficacy for physical activity. No gender by determinant interaction effects were observed, and girls reported significantly greater perceived reinforcement for healthy eating than did boys.
  
  
  CONCLUSIONS
  The CATCH program was effective in changing the psychosocial variables likely to influence a reduction in behavior for cardiovascular disease. The study is significant in that it demonstrates the viability and effectiveness of a sustained multifaceted intervention in a preadolescent population. The results point to a need for greater understanding of adolescent developmental issues and the role of community environment (particularly social support) in creating effective curricula.
authors.affiliation: University of Texas at Austin, Austin, Texas, 78712, USA.
authors.forename: E
authors.initials: E
authors.lastname: Edmundson
authors.forename: G S
authors.initials: GS
authors.lastname: Parcel
authors.forename: H A
authors.initials: HA
authors.lastname: Feldman
authors.forename: J
authors.initials: J
authors.lastname: Elder
authors.forename: C L
authors.initials: CL
authors.lastname: Perry
authors.forename: C C
authors.initials: CC
authors.lastname: Johnson
authors.forename: B J
authors.initials: BJ
authors.lastname: Williston
authors.forename: E J
authors.initials: EJ
authors.lastname: Stone
authors.forename: M
authors.initials: M
authors.lastname: Yang
authors.forename: L
authors.initials: L
authors.lastname: Lytle
authors.forename: L
authors.initials: L
authors.lastname: Webber
mesh_terms: D000293:Adolescent; D002318:Cardiovascular Diseases / Q000517:prevention & control*; D002648:Child; D004032:Diet / Q000523:psychology*; D015444:Exercise / Q000523:psychology*; D005260:Female; D015438:Health Behavior; D007722:Health Knowledge, Attitudes, Practice; D006293:Health Promotion / Q000458:organization & administration*; D006801:Humans; D008297:Male; D015397:Program Evaluation; D012056:Reinforcement, Social; D012572:School Health Services / Q000458:organization & administration*; D011795:Surveys and Questionnaires; D014481:United States