(in contrast to entire groups, as in selective prevention) who show biological markers for obesity or who are already overweight but do not meet the diagnostic criteria for obesity. Risk factors for such individuals include a family history of obesity as well as biological markers and the development of early symptoms of the disorder. Although research is still in the preliminary stages of identifying reliable biological markers, programs that target individuals who are already overweight (or whose health risks are increased owing to their weight and/or a sedentary lifestyle) may prove effective.
There are two outcome measures for indicated prevention programs:
reduction in the number of obese people who go on to develop obesity-related comorbidities (e.g., reduced adult obesity among overweight children receiving intervention in childhood); and
increase in the number of obese people who are successful in attaining and maintaining relatively small weight losses (e.g., 10 percent of initial body weight) and a decrease in the number who gain a small amount of weight (e.g., 2 kg).
Promising results have been reported by Epstein et al. (1990c). Although this study could also be considered a treatment program for obese children (since subjects had to be ≥ 20 percent over ideal body weight for age, height, and sex), its goal was to prevent adult obesity. We include this study as an example because the same approach could be adopted with children who are overweight but not obese. In the study, Epstein and colleagues used a prospective, randomized design to examine the effects of behavioral, family-based treatment on percent overweight and growth over 10 years in obese 6- to 12-year-old children. Obese children with their parents were randomized to three groups that were provided similar diet, exercise, and behavior-management training, but differed in the way in which behavioral reinforcement was provided. In one group, both parent and child were reinforced; in the second only the child was reinforced. The third group was a nonspecific control group in which families were reinforced for attendance only. Children in the first group showed significantly greater decreases in percent overweight after 5 and 10 years (-11.2 and -7.5 percent, respectively) than children in the nonspecific control group (+7.9 and +14.3 percent, respectively). Results of