The impact of social networks on parents' vaccination decisions

Parents decide whether their children are vaccinated, but they rarely reach these decisions on their own. Instead parents are influenced by their social networks, broadly defined as the people and sources they go to for information, direction, and advice. This study used social network analysis to formally examine parents' social networks (people networks and source networks) related to their vaccination decision-making. In addition to providing descriptions of typical networks of parents who conform to the recommended vaccination schedule (conformers) and those who do not (nonconformers), this study also quantified the effect of network variables on parents' vaccination choices.

This study took place in King County, Washington. Participation was limited to US-born, first-time parents with children aged ≤18 months. Data were collected via an online survey. Logistic regression was used to analyze the resulting data.

One hundred twenty-six conformers and 70 nonconformers completed the survey. Although people networks were reported by 95% of parents in both groups, nonconformers were significantly more likely to report source networks (100% vs 80%, P < .001). Model comparisons of parent, people, and source network characteristics indicated that people network variables were better predictors of parents' vaccination choices than parents' own characteristics or the characteristics of their source networks. In fact, the variable most predictive of parents' vaccination decisions was the percent of parents' people networks recommending nonconformity.

These results strongly suggest that social networks, and particularly parents' people networks, play an important role in parents' vaccination decision-making.