Understanding the Social Networks That Form within the Context of an Obesity Prevention Intervention

Abstract

Background. Antiobesity interventions have generally failed. Research now suggests that interventions must be informed by an understanding of the social environment. Objective. To examine if new social networks form between families participating in a group-level pediatric obesity prevention trial. Methods. Latino parent-preschool child dyads (N = 79) completed the 3-month trial. The intervention met weekly in consistent groups to practice healthy lifestyles. The control met monthly in inconsistent groups to learn about school readiness. UCINET and SIENA were used to examine network dynamics. Results. Children's mean age was 4.2 years (SD = 0.9), and 44% were overweight/obese (BMI ≥ 85th percentile). Parents were predominantly mothers (97%), with a mean age of 31.4 years (SD = 5.4), and 81% were overweight/obese (BMI ≥ 25). Over the study, a new social network evolved among participating families. Parents selectively formed friendship ties based on child BMI z-score, (t = 2.08; P < .05). This reveals the tendency for mothers to form new friendships with mothers whose children have similar body types. Discussion. Participating in a group-level intervention resulted in new social network formation. New ties were greatest with mothers who had children of similar body types. This finding might contribute to the known inability of parents to recognize child overweight.

Figure 1

Flow of participants through the trial.

Figure 2

Mapping of social network changes over 3-month intervention. Each graph shows the study participants who have social ties with other study participants. These maps illustrate several points: First, some study participants already knew each other at baseline. This reflects the fact that the most effective recruitment strategy in this Latino population was word of mouth referrals. Importantly, there were no differences in preexisting network ties between control and intervention groups. Second, while some study participants already knew other study participants at baseline, half did not, and thus are not shown here, reflecting the average number of ties of 1.5 at baseline. Third, after the intervention, each group increased in the number of participants who had ties with others in the group.