Surveys were returned by 1367 (56.1%) of the 2435 parents of selected children, including 391 (48.6%) of 805 parents of children with exemptions and 976 (59.9%) of 1630 parents of fully vaccinated children. Of the 391 parents of children that were identified by their school as having an exemption to one or more vaccines, 114 were excluded from analysis; 86 indicated that their child was fully vaccinated and 28 respondents provided valid medical contraindications to vaccination. The remaining 277 parents of children with nonmedical exemptions, as well as all 976 parents of fully vaccinated children, were included in the analysis [22
The majority of respondents (n = 997, 79.6%) reported using between 2 and 6 sources for information on vaccines, while few reported using only a single information source (n = 55, 4.4%). The most commonly used source of vaccine information was the child's healthcare provider (n = 1149, 91.7%), followed by Vaccine Information Statements (printed materials from healthcare providers) (n = 1052, 84.0%) and parents/friends (n = 674, 53.8%). Six vaccine information sources were identified by approximately three-quarters or more of respondents as good or excellent sources of information, including healthcare provider's advice (n = 1004, 81.8%) and the US Centers for Disease Control and Prevention and the National Immunization Program (n = 911, 81.6%). Among all respondents, 39.9% (n = 425) reported that they view the Internet as a good or excellent source of vaccine information. Overall, 249 respondents (19.9%) reported using the Internet as a source of vaccine information (hereafter referred to as “Internet users”; the remaining 1,004 respondents who reported not using the Internet as a source of vaccine information are hereafter referred to as “Non-Internet users”).
Internet users were more likely to have at least a college degree (aOR, 1.49; 95% CI, 1.12–2.00) and have a gross annual household income of $70,000 or higher (aOR, 1.41; 95% CI, 1.04–1.91). There were no significant differences in parental age, race/ethnicity, or choice of child's primary healthcare provider between Internet users and non-Internet users (). Internet users were more likely to have a child with an exemption to at least one vaccine than non-Internet users (OR, 3.53, 95% CI, 2.61–4.76) ().
Demographic characteristics as predictors for Internet use as a source of vaccine information among parents of school aged children.
Internet users were significantly more likely than parents who did not use the Internet to believe that the National Vaccine Information Center was a good or excellent source of vaccine information (aOR, 1.69, 95% CI, 1.12–2.55). The National Vaccine Information Center was previously known as Dissatisfied Parents Together, which was also included as an information source of interest in the survey; there was no difference in the perception of Dissatisfied Parents Together across Internet user category. Internet users were also more likely to regard alternative healthcare providers (aOR, 1.55; 95% CI, 1.12–2.14) as a good or excellent source of information. Internet users were less likely than non-Internet users to consider the following good or excellent sources of vaccine information: healthcare providers (aOR, 0.59; 95% CI, 0.42–0.85), Vaccine Information Statements (aOR, 0.49; 95% CI, 0.35–0.69), professional organizations (aOR, 0.56; 95% CI, 0.39–0.80), local or state health departments (aOR, 0.60; 95% CI, 0.43–0.84), and the CDC (aOR, 0.57; 95% CI, 0.39–0.83) ().
Perceptions of vaccine information sources among parents who did or did not use the Internet for vaccine information.
Internet users more commonly held key beliefs about vaccines that are not supported by scientific research on vaccines than non-Internet users (). Internet users were less likely than non-Internet users to believe that vaccines strengthen the immune system (aOR, 0.65; 95% CI, 0.46–0.92) and more likely to believe that children get more immunizations than are good for them (aOR, 2.88; 95% CI, 2.03–4.10), healthy children do not need immunizations (aOR, 2.06; 95% CI, 1.28–3.31), immunizations do more harm than good (aOR, 2.47; 95% CI, 1.60–3.81), and that a child's immune system could be weakened by too many immunizations (aOR, 1.74; 95% CI, 1.25–2.43).
Association of vaccination beliefs with Internet use as a source of vaccine information among parents of school aged children.
Internet users were also significantly more likely to be opposed to immunization requirements because immunization requirements go against the freedom of choice (aOR, 2.36; 95% CI, 1.64–3.39) and because parents know what is best for their children (aOR, 2.68; 95% CI, 1.75–4.09) than non-Internet users. Additionally, Internet users were less likely to recognize the benefits of immunization for their child (aOR, 0.39; 95% CI, 0.25–0.59) as well as the community benefits from vaccination (for the child's family, playmates, and neighbors) (aOR, 0.53; 95% CI, 0.36–0.76). Relatedly, these parents also had lower perceptions of disease susceptibility, vaccine protectiveness and vaccine safety (). No significant differences were observed for trust in government or trust in healthcare providers by Internet vaccine information seeking behaviors.
Association of disease, vaccine, and trust constructs with Internet use as a source of vaccine information among parents of school aged children.