摘要：Objectives. We used a participatory process to develop an obesity intervention appropriate for elementary school personnel. Methods. A randomized controlled trial included 16 school worksites (8 intervention, 8 control). Intervention schools formed committees to develop and implement health promotion activities for employees. Anthropometric and self-report data were collected at baseline and postintervention (2 years later). The primary outcome measures were body mass index (BMI), waist–hip ratio, physical activity, and fruit and vegetable consumption. Results. After adjustment for age, ethnicity, and job classification, employees in intervention schools reduced their BMI by an average of 0.04 kg/m2, and those in control schools increased their BMI by an average of 0.37 kg/m2. Comparisons for waist–hip ratio, weekly physical activity minutes, and fruit and vegetable consumption were not significant. Conclusions. The participatory process appeared to be an effective means for stimulating change. The intervention may have slowed and perhaps reversed the tendency of adults to gain weight progressively with age. Obesity in the United States is a major cause of preventable disease. Among adults, 31% of men and 33% of women are considered obese (body mass index [BMI; weight in kilograms divided by height in meters squared] ≥ 30 kg/m2), 1 and prevalence of obesity is higher among ethnic minorities than among non-Hispanic Whites. Obesity is associated with life-threatening chronic disease 2 and was responsible for the largest increase among causes of death in the decade between 1990 and 2000. 3 Health problems associated with obesity cost the health care system an estimated $75 billion per year, 4 and indirect costs, such as loss of work time, further inflate this figure. In his Call to Action to Prevent and Decrease Overweight and Obesity , the surgeon general cited schools and worksites as environments that can promote the development of healthful behaviors. 5 Almost 6 million adults work in public schools in the United States. 6 The school environment is thought to be conducive to worksite health promotion because of access to facilities for physical activity and for educational purposes. 7 Staff wellness is 1 of the 8 components of the Coordinated School Health Model, a conceptual model that addresses the school environment. 8 , 9 Health promotion in the school setting has the potential of reducing absenteeism, lowering turnover rates, and lowering insurance rates. In addition to these direct benefits, healthy teachers create an optimistic school climate, serve as role models to students, and reinforce positive health messages. These teachers are also more likely to incorporate health education into their lessons. 10 Broadly, healthy employees influence the school community, including parents and students. 7 We used a participatory process to develop an intervention appropriate for elementary school personnel. The goal was to reduce obesity by promoting healthy dietary and exercise behaviors among personnel in a large, urban school district. Community-based participatory research is a cooperative process that engages community members and researchers as equals, 11 involving community members in designing and implementing interventions appropriate for their needs. 12 This approach has been shown to enhance effectiveness and save time and money. 13 The participatory process may foster an enhanced sense of ownership, thereby increasing the likelihood that interventions will be institutionalized and sustained after startup resources have been exhausted. The overall theoretical umbrella for this research is social cognitive theory, 14 emphasizing the person, the environment, and their interaction. Self-efficacy, or the individual's belief that she or he can perform the behaviors to reach the desired goal, is a key personal construct that has been associated with behavior change. Perceived barriers to change, such as lack of access to healthful food or opportunities for exercise, are an important aspect of the environmental domain. Impressions of the social norms regarding behaviors are relevant to the interaction of the person and the environment. The participatory process of developing the intervention can enhance the extent to which school personnel share norms about the value of maintaining a healthy weight and the means to achieve it. The emphasis on social norms in behavior change is also compatible with the theories of reasoned action and planned behavior. 15 , 16 In any group intervention, but particularly one that incorporates a participatory process, the group environment becomes part of the intervention. Thus, an environment that builds camaraderie and fosters support can be a crucial element in the success of the intervention. In the analyses presented here, we tested 2 hypotheses: (1) individuals employed at school worksites randomly assigned to be intervention schools would be significantly more likely to lose weight (as evidenced by reduction in BMI and waist–hip ratio) than individuals employed at comparable control worksites; and (2) individuals in intervention schools would be significantly more likely to change diet and physical activity behaviors than individuals at control worksites. In sum, the hypotheses address the questions of whether the intervention worked and how it worked.
