THE EFFECTS OF THE CHILD AND ADOLESCENT TRIAL FOR CARDIOVASCULAR HEALTH UPON PSYCHOSOCIAL DETERMINANTS OF DIET AND PHYSICAL-ACTIVITY BEHAVIOR

Background. The Child and Adolescent Trial for Cardiovascular Health i s a multisite study of a school-based intervention to reduce or preven t the development of risk factors for cardiovascular disease. The purp ose of this paper is to present the evaluation results of the 3-year i ntervention, focusing upon the psychosocial variables conceptualized a s determinants of dietary and physical activity behaviors. Methods. A total of 96 schools across four study sites (California, Louisiana, Mi nnesota, and Texas) were randomized to two treatment conditions: inter vention and control. Pre- and postmeasurements on the health behavior questionnaire were collected from over 6,000 students. The data analys es utilized a nested design approach in which schools served as the pr imary unit of analysis. Repeated-measures multivariate analyses were a pplied 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 knowl edge, intentions, self-efficacy, usual behavior, and perceived social reinforcement for healthy food choices (P < 0.0001 for these five vari ables) after 3 years. Intermittent effects were observed for perceived support and self-efficacy for physical activity. No gender by determi nant interaction effects were observed, and girls reported significant ly greater perceived reinforcement for healthy eating than did boys. C onclusion. The CATCH program was effective in changing the psychosocia l variables likely to influence a reduction in behavior for cardiovasc ular disease. The study is significant in that it demonstrates the via bility and effectiveness of a sustained multifaceted intervention in a preadolescent population. The results point to a need for greater und erstanding of adolescent developmental issues and the role of communit y environment (particularly social support) in creating effective curr icula. (C) 1996 Academic Press, Inc.