摘要：Objectives. We examined the association of Internet-related communication inequalities on human papillomavirus (HPV) vaccine awareness and infection knowledge. Methods. We drew data from National Cancer Institute’s 2007 Health Information National Trends Survey (n = 7674). We estimated multivariable logistic regression models to assess Internet use and Internet health information seeking on HPV vaccine awareness and infection knowledge. Results. Non–Internet users, compared with general Internet users, had significantly lower odds of being aware of the HPV vaccine (odds ratio [OR] = 0.42; 95% confidence interval [CI] = 0.34, 0.51) and knowing that HPV causes cervical cancer (OR = 0.70; 95% CI = 0.52, 0.95). Among general health information seekers, non–Internet seekers compared with Internet information seekers exhibit significantly lower odds of HPV vaccine awareness (OR = 0.59; 95% CI = 0.46, 0.75), and of knowing about the link between HPV infection and cervical cancer (OR = 0.79; 95% CI = 0.63, 0.99) and the sexual transmission of HPV (OR = 0.71; 95% CI = 0.57, 0.89). Among cancer information seekers, there were no differences in outcomes between Internet seekers and non–Internet seekers. Conclusions. Use of a communication channel, such as the Internet, whose use is already socially and racially patterned, may widen observed disparities in vaccine completion rates. In 2006, the Food and Drug Administration approved the first vaccine for the 4 major types of human papillomavirus (HPV), 2 of which cause approximately 70% of cervical cancer cases in the United States. 1 Many health officials and researchers have indicated that appropriate uptake of the vaccine could serve as a way to eliminate disparities in cervical cancer rates seen throughout the United States. 2 However, according to the Centers for Disease Control and Prevention’s (CDC’s) most recent National Immunization Survey–Teen, only 37% of US female adolescents aged 13 to 17 years initiated the HPV vaccine series (≥ 1 dose) in 2008 and a mere 18% of teens completed the necessary 3-dose series. 3 More important than the overall low series completion rates nationally are the noted disparities across racial and social groups. Several large-scale studies, including the 2008 National Immunization Survey, have reported that, although African American and Hispanic girls are more likely to initiate the series, they are less likely to complete the 3-dose series compared with their White counterparts. 4–6 In addition, reports indicate that girls living in poorer states and in neighborhoods with low education levels, and those who rely on public insurance are also less likely to complete the vaccine series compared with girls living in wealthier states and in neighborhoods with higher aggregate education levels, and those who are covered by private insurance. 4,6,7 If these racial and social disparities in completion rates continue, they may further exacerbate what is already an unequal burden of cervical cancer among these groups of women. We suggest that the discrepancy between initiation and completion rates may in part be attributable to the well-documented knowledge gaps among lower–socioeconomic status (SES) and minority parents, caregivers, and other influential adults about what HPV is, how it is spread, and how it can be prevented across these vulnerable groups. 8–10 The initiation shot typically occurs during a well-child visit along with a host of other vaccinations, raising the issue as to whether patients and guardians are truly informed of what vaccinations they are receiving, but completion shots need to be separately scheduled. Knowledge and awareness therefore may play a larger role in the decision-making process as to whether a child or adolescent will complete the series because they will occur outside the normal doctor’s visit. What is less known, and what needs to be examined to reduce the disparities in completion rates, are the driving factors behind these knowledge gaps. We argue that communication is one thread that could potentially connect the different levels of social determinants that could ultimately explain individual health status and population-level health because of the different functions it serves. 11–13 If so, communication inequalities—differences among social groups in accessing, seeking, processing, and using health information—could play an important role in shaping HPV-related knowledge gaps, which may, in turn, influence vaccine completion rates. 11 In the case of HPV, there are a number of communication inequalities that warrant examination. For example, disparities in completion rates may in part be influenced by a breakdown in patient–provider communication. However, there is a substantial body of evidence indicating the ever-growing reliance on the Internet, over physicians, as an important source of health information. 11 Therefore, we offer that HPV-related knowledge gaps and communication inequalities may primarily be a product of (1) the vaccine manufacturer’s reliance on Internet-based direct-to-consumer advertising (DTCA) as the main information delivery system for both the infection and the vaccine, combined with (2) differential access and use of the Internet among those of low SES and minority populations. Merck’s Gardasil is one of the first cancer vaccines for prophylactic use, and as such, they created a lucrative market with revenue estimates close to $3.2 billion by the year 2012. 14 Because Merck has a large financial stake in the success of the vaccine, industry analysts report that an overwhelming majority of the messages and information that the public receives about HPV and the vaccine are somehow linked to the pharmaceutical developer. 14,15 If one considers how limited public health funds are, there is a perceived benefit of having a large pharmaceutical company with a substantial marketing budget take on the burden of educating the public about the harmful effects of the disease while advertising its product. The goal of print and television DTCA, however, is to make consumers aware of the brand name of a drug and to drive them to perform external searching or, rather, information seeking, which is the purposive and deliberate seeking of information on a topic because of its salience and need. 16 External information seeking is recognized in the health marketing industry as the way consumers can expand their knowledge of the drugs represented. 17 Moreover, research shows that consumers are increasingly turning to the Internet, over other channels, to search for more information about a drug they saw on television. 18,19 With increased advertising spending, concerns have been raised that print and TV DTCA may mislead consumers with unbalanced and incomplete information making the reliance on external searching, specifically Internet information seeking, even more crucial. 19 Unfortunately, reliance on Internet-based external searches to provide needed information for informed decision-making on HPV vaccination could only exacerbate existing knowledge gaps. Research has shown that education is strongly associated with consumer information seeking as well as with time spent looking for the information. 20 Research also shows that DTCA is not appropriate for low-literacy audiences as the information provided is too complex and written at a high reading grade level. 21–23 There is the additional consideration that many low-SES and minority groups lack Internet access as well as the needed computer literacy skills to adequately search the Internet for health-related information. 24 Recent analyses of the National Cancer Institute’s Health Information National Trends Survey (HINTS) 2007 offer further evidence of digital disparities. Although overall penetration of Internet access in the United States has increased to 70%, the digital divide remains with nearly half of Hispanics and non-Hispanic Blacks lacking Internet access even after controlling for other important variables. The same is true across socioeconomic strata with adults with lower education levels and income having significantly lower odds of Internet access compared with their higher-SES peers. 25 Additional research on the 2007 HINTS data also highlight disparities in online health information seeking with lower odds of using the Internet as a first source of health information among those with lower incomes and education levels, and for Blacks compared with Whites. 26 Moreover, limited computer literacy skills could potentially interact with limited health literacy skills among low-SES and minority groups to not only inhibit the initiation of Internet-based health information seeking but also result in procuring misinformation because of improper Web searching. This misinformation could negatively impact HPV and vaccine knowledge as well vaccination uptake and completion rates. Our goal was to examine the association between Internet-based communication and knowledge of the HPV vaccine with the hope of identifying more effective approaches to improve completion rates among underserved groups. In light of the Internet-based communication strategy for the HPV vaccine emphasized by Merck, we hypothesized that those individuals and groups that do not rely on the Internet for health information are likely to have lower levels of awareness and knowledge of both HPV and the HPV vaccine.
