The effect of adult participation in a school-based family intervention to improve children's diet and physical activity: The child and adolescent trial for cardiovascular health

Background. There are strong theoretical reasons for including a family component with a school-based intervention aimed at eating, activity, and smoking behaviors, but the empirical findings to date are limited and show mixed results. The overall CATCH family intervention added only knowledge and attitudinal effects, but no additional behavioral outcomes. This study provides a dose analysis of the family component of the CATCH study by assessing the effect of the level of adult participation. Method. This secondary analysis included students who attended a CATCH family intervention school during all 3 years of the study, The extent of the adult-child interaction, the key aspect of the CATCH family intervention, was measured by the number of activity packets that an adult household member completed with the child. Multiple regression analysis was used to assess the association of adult participation with the child's knowledge, attitudes, and behaviors related to diet and physical activity. Results. Statistically significant results suggested that dose effects were found for knowledge and attitudes related to diet and physical activity. These effects were more pronounced for minority and male students. Conclusions. These results suggest that dose response of a family intervention has been shown in the acquisition of positive knowledge and attitudes toward health habit changes. The methodology of dose response can be applied to other health promotion projects. (C) 1996 Academic Press, Inc.