Breast cancer is the second most common cancer diagnosed in women [1]. Women, particularly those with a personal or family history of the disease and mothers with daughters, are concerned about what they can do to reduce the risk of breast cancer [2-7]. In addition, when mothers advise their daughters about how to reduce the risk, daughters tend to follow their advice into adulthood [7]. Although clinicians, scientists, and advocacy groups prioritize cancer screening to reduce the risk (eg, mammograms and genetic testing), scientists have discovered that environmental exposures (eg, having contact with certain chemicals or particles through food, air, water, or touch) impact women’s risk [8].

In response to increasing research on breast cancer risk and environmental exposures, Congress passed the Breast Cancer and Environmental Research Act in 2008. This resulted in the initiation of the Interagency Breast Cancer and Environmental Research Coordinating Committee (IBCERCC), which was tasked with examining the state of this research. Their report identified 7 recommendations, 2 of which centered on the need for scientists to become engaged in dissemination, specifically prioritizing community stakeholder engagement and translating research for the public [9].

The authors are members of 1 group actively involved in the creation and dissemination of such research—the Breast Cancer and the Environment Research Program (BCERP). Founded in 2003 and funded by the National Institute of Environmental Health Sciences (NIEHS) and the National Cancer Institute (NCI), BCERP researchers have conducted decades of studies linking environmental factors and breast cancer risk. This includes identifying endocrine-disrupting chemicals (eg, phthalates and bisphenol A [BPA]) that could increase women’s risk and are found in some personal care and household products (eg, shampoo, detergent, and plastic bottles) [8]. BCERP provides actionable steps that women and their family members can take to reduce their exposure to these environmental risks. In recent years, BCERP has funded projects focused specifically on dissemination. The program currently disseminates this evidence-based information free to the public via their website [10].

Although women seek Web-based information about how to reduce personal and familial risk of breast cancer [11], they may not be obtaining reputable or scientifically based information that organizations such as BCERP provide. Readability and accessibility are also issues. A recent review of breast cancer and environmental risk information online showed that most content is not disseminated at a readable level with health literacy in mind [12]. There is also a plethora of information on the internet from divergent sources, including medical websites that are not regulated [13]. Websites are discovered based on users’ search terms with no guarantee that reputable sources such as BCERP are even reached. Thus, as the IBCERCC report also identified, researchers need to do a better job of disseminating breast cancer information in ways that reach women. Dissemination approaches should also strive to reach more women or have the potential for rapid diffusion of information, the process by which information is spread across channels rapidly [14].

Social media offers an ideal dissemination channel with the potential to reach an expansive group of women. Current evidence [15] has shown that:

Social media platforms, such as blogs, offer a way to disseminate health information rapidly and expansively, educate the public, and promote healthy behavior. Still, careful application and evaluation is needed to obtain the desired outcomes [15] as blog-based interventions can result in limited exposure, messages not being tailored to the targeted audience, or messages that do not account for health literacy or culture [12,13,16]. Also, when it comes to online dissemination about environmental breast cancer risk, accuracy is of concern [12]. This is particularly true with blogs [17], which have been shown to be the least accurate in comparison with other online sources [12].

A recent review also showed that online information about environmental exposures is particularly complicated and, at times, misunderstood [12], with more commercial-focused online sources reporting known risk associations within exposures like deodorant, which opposes research showing no associated risk presented on more credible sites (eg, American Cancer Society). Additionally, this review found that while research may be presented accurately, the conclusions are not always accurately drawn and appear to be driven by personal motivations [12].

To ensure access and accuracy in the dissemination of breast cancer risk information, scholars have recently called for a community-engaged approach, linking scientists with community stakeholders to ensure that the public has access to the information and that it is disseminated in a manner that is readable and relatable [18]. In line with the IBCERCC’s recommendation [9], mothers who blog, or mommy bloggers, are an ideal community partner to disseminate information via blogs to reach women. Their blog posts could integrate scientifically based information in a manner that blog readers can identify. Also, blogs written by mothers are increasingly recognized as a channel that women utilize to make personal and family health–related decisions [19-21], and as such, mommy bloggers are often viewed as relatable and trustworthy by other mothers.

In addition, evidence-based strategies are integral to successfully disseminating health information via blogs [15]. These strategies include tailoring messages with the audience or readers in mind. Tailoring may involve user-generated (ie, blogger-generated) content to promote acceptance (by using a trusted source that content readers identify with), encouraging multipronged approaches (multiple social media platforms), integrating theory during intervention development, and using tools to evaluate the impact of the intervention on readers [15,22].

With these evidence-based strategies in mind, we aimed to develop and evaluate a targeted blog intervention, teaming with mommy bloggers to disseminate scientifically informed breast cancer and environmental risk information (adapted from BCERP) with the potential for rapid diffusion. The goal was to influence readers’ (ie, mothers’) exposure to, acceptance of, and beliefs about environmental risks while promoting intentions to adopt risk-reducing behaviors. In addition to testing the efficacy of this approach, we sought to shed light on how such an intervention may extend farther than targeted readers or how readers may share the information across other platforms.

For many, the internet is a primary source of health information, including information about reducing breast cancer risk [11,23,24]. People increasingly seek health information through social media, such as Facebook, Twitter, and blogs, where knowledge is shared within a relational network facilitated through an online community [25]. The interactive and relational nature of social media allows individuals to connect with and reach broader audiences to address a range of health issues [26,27]. Therefore, blogs may represent an optimal social media channel for disseminating breast cancer risk information [19].

Blogs can be rich in information and promote interaction among bloggers and readers. For instance, bloggers provide unique content for their readers compared with other online communities [28]. They display a keen understanding of readers’ health needs and beliefs [19,28] and typically deliver information in varied forms (eg, text, multimedia, and links to Web resources) that are shared interactively via bloggers’ posts and exchanges of readers’ comments [19,29]. This online interaction generates a larger community network, extending beyond the blog [30-32]. Bloggers and readers may share blog content online (eg, via Facebook, Twitter, and Pinterest) and offline (eg, with family, friends, coworkers, and community groups). Thus, blogging can reach a broad audience.

In addition to facilitating interaction and reach, blogs represent a unique channel where specific audiences (such as mothers) can be reached and influenced. Bloggers can customize health information in ways that readers relate to, as bloggers are likely perceived by readers as being similar in terms of beliefs, experiences, and language [33,34]. In other words, blog readers identify with the bloggers (eg, as a woman, mother, or survivor). This increases the likelihood of readers’ acceptance, sharing, and adoption of the information posted by the blogger [35,36].

Currently, there are about 3.9 million mothers in the United States who identify as a blogger, and many mothers with children at home turn to blogs for advice about health issues [19,37]. Blogs written by mothers or those that focus on motherhood topics—sometimes called mommy blogs —offer the possibility of reaching an important target audience for breast cancer risk information: women and their family members [20,38,39].

Readers relate to their blogs in part because mommy bloggers routinely tailor messages to their target audience (eg, using strategies such as feminine rhetoric, humor, or personal stories with photographs that women identify with) [40-43]. Bloggers also direct their readers to relevant and accurate health information on the internet [44]. Given their trusted status among mothers, mommy bloggers could be used to disseminate risk-reducing information and persuade readers to adopt or respond to it [45]. In line with Rogers’ widely used diffusion of innovation theory [14], mommy bloggers may be key to disseminating such information.

As diffusion of innovation theory purports, early adopters or innovators (readers) and opinion leaders (bloggers) are central to the dissemination of new ideas to the public. Mommy bloggers could promote rapid diffusion of the information through larger blogging networks when bloggers adopt the message (ie, post the content and endorse it), which can influence readers to do the same. Thus, bloggers can be viewed as opinion leaders who may drive diffusion and uptake of environmental breast cancer risk information by their readers [14,19,45]. The risk-related content may heighten the urgency of the message, and the message’s effects may be further amplified through bloggers’ and readers’ comments, shares, and likes [46].

This interactive and dynamic diffusion of information also has the potential to influence women’s behavior, which is essential to reducing cancer risk. Blog intervention studies show that blogger-reader interactions can create a sense of immediacy about health topics that encourages readers’ adoption of healthy behaviors [47]. Moreover, the tailored context of the blog, in conjunction with readers’ perceived source similarity [35], can influence women’s adoption of recommended health behaviors [47].

Despite the potential for mommy bloggers to serve as trusted or relatable sources to disseminate breast cancer risk information to mothers, it is critical that bloggers disseminate accurate, scientifically informed content [12]. Moreover, content should in part be user-generated with a target audience in mind, meaning that it should be produced in part with the bloggers’ input [15]. To achieve this, collaborative message development (between scientists and bloggers) is warranted to ensure women receive accurate information in a format they trust and relate to.

As described, federally funded BCERP scientists and community partners have developed and disseminated research to bring awareness to the public about linkages between environmental exposures and breast cancer risk. BCERP provides several educational materials online, including a toolkit for mothers with daughters. These mother-daughter–focused materials specifically address how mothers can reduce their own and their daughter’s risk by adopting healthier lifestyle choices together (eg, eliminating products with BPA and phthalates).

Many mothers with daughters are concerned and feel uncertain about breast cancer prevention and their daughters’ risk [2,3,48]. However, when mothers advise daughters about how to reduce risk, daughters adhere to their mother’s advice into adulthood [7]. Talking about risk can be challenging. Younger daughters often avoid or withdraw from such conversations [4,49], which can trigger a physiological stress response[50]. Mothers have reported using third-party approaches (eg, a magazine article) to prompt interaction and ease their daughter’s comfort during discussions [3,4]. Relatedly, recent research shows that third-party Web-based approaches (eg, videos about BPA/perfluorooctanoic acid and radiation risk) favorably influence mothers’ and daughters’ prevention behavior [16,51].

Mommy bloggers’ posts could change mothers’ knowledge and beliefs about environmental breast cancer risk factors and simultaneously function as a third-party approach to facilitate mother-daughter communication. Even though the information on BCERP’s website is scientifically informed and expansive, the format and manner in which these materials (a brochure, flyer, and public service announcement) are delivered assume women will obtain them, first by finding their website and then by reading them on their own. Passive dissemination approaches such as these do not ensure the information reaches the target audience and, when used alone, are not likely to be translated to practice or result in behavioral change [52]. Moreover, these materials are often lengthy and not in a format ideal for social media dissemination.

A more active diffusion of information or dissemination approach on an interactive Web platform in which an influencer (eg, blogger) communicates with women (their readers) is more likely to reach the targeted audience. Additionally, this approach may prompt interaction within and outside the blog network. By teaming with mommy bloggers, the evidence-based information could be integrated into a user-generated format ideal for social media and delivered in a manner that their readers (mothers) can relate to.

As the aforementioned research demonstrates, mothers look to mommy bloggers for health information. By partnering with mommy bloggers to disseminate evidence-based environmental risk information about how mothers (and daughters) can reduce breast cancer risk, we sought to increase women’s exposure to, satisfaction with, and acceptance of environmentally focused risk-reducing information. Thus, the first hypothesis (H1) was posited:

Given the interactive nature of blogging, we also wanted to encourage the diffusion of this information within women’s larger social networks. Previous research has not examined how intervention messages stemming from mommy blogs might influence interaction and information sharing among other social media platforms. Therefore, the following research question (RQ) was posed:

Behavior change is the ultimate goal of a health promotion intervention. According to the integrative model of behavioral prediction (a reasoned action theory approach to health promotion), several antecedents of behavior change should be evaluated to understand and predict whether women will take action [53,54]. These variables include acceptance of a health-related message, beliefs about health and risk, and intention to change. On the basis of this framework, we posited the second hypothesis (H2):

Finally, to reach a larger audience, it is critical that this information is disseminated (or diffused) through channels perceived as optimal by women [15]. Therefore, we aimed to understand mothers’ preferred communication channels for breast cancer and environmental risk and prevention information. More than half of the US population use 2 or more social media platforms [55], and some individuals prefer traditional, interpersonal (eg, face-to-face) communication channels because of cultural norms about discussing health and risk topics [56]. To ensure women perceive mommy bloggers as an optimal channel but also provide opportunities to refine our intervention as necessary, we sought to learn about perceived optimal channels more broadly. Therefore, the following inquiry was posed:

After the institutional review board approval, 3 groups of participants were recruited: (1) bloggers involved in the intervention, (2) readers exposed to the intervention (intervention group), and (3) readers not exposed to the intervention (comparison group). A convenience sample of mommy bloggers, all women, was recruited through The Motherhood [57], a network of more than 3000 diverse mothers who blog about various topics including health. During the recruitment process, efforts were made to find participants of different racial or ethnic groups and geographic locations, as well as prior experiences with breast cancer (either personally and/or by family members). A total of 75 mommy bloggers agreed to participate in the intervention (see Table 1 for blogger characteristics).

Upon consent, all participants completed an online survey with items about sociodemographics and breast cancer history. About 35 mommy bloggers had previously written about breast cancer in their blogs in the past year. All of the bloggers in the sample had children and 52 bloggers had daughters, specifically. Bloggers posted messages on their blogs to recruit readers for the intervention group.

The reader intervention group was comprised 445 blog readers (435 women and 10 men) who follow one or more of the 75 bloggers involved in the intervention. The participating mommy bloggers were asked to recruit their readers and direct them to an online postintervention survey link. A total of 353 blog readers (341 women and 12 men) made up the reader comparison group. To minimize contamination between the 2 groups, readers in the comparison group were recruited through a separate set of mommy bloggers who were affiliated with The Motherhood network, but who did not blog about breast cancer and were not involved in the intervention (see Table 2 for blog readers’ characteristics). The comparison group bloggers wrote about a wide range of issues, including parenting concerns and other health issues besides breast cancer.

The reader intervention group completed an online postintervention survey after the message exposure period. In terms of frequency of use, 367 intervention group respondents reported reading mommy blogs one or more days per week (78 indicated less than once per week). Many (n=280) reported having daughters.

Blog readers recruited for the reader comparison group completed the same postintervention online survey as the intervention group. Respondents from this group (n=307) mentioned reading mommy blogs one or more days per week (46 reported less than once per week). Reader comparison group respondents (n=227) also reported having daughters. Participants in the intervention and comparison groups only differed significantly by age (t₇₉₄=2.110; P=.03).

Intervention bloggers were provided incentives depending on their reach. Bloggers with an overall reach of up to 100,000 were given US $125; bloggers with an overall reach of up to 200,000 were given US $200; and bloggers with an overall reach above 250,000 were given US $300. Bloggers who disseminated the reader comparison group survey were offered US $50. Readers had the option to enter a raffle to win 1 out of 5 US $100 gift cards.

The blog reader survey included a variety of measures that are consistent with the diffusion of innovation theory [14], including measures of message exposure, message satisfaction, message acceptance or influence, and likelihood of sharing the BCERP messages with the members of other social networks.

The aim of this study was to examine whether a targeted intervention in which mommy bloggers disseminate evidence-based information could increase mothers’ exposure to and dissemination of breast cancer environmental risk and prevention information and, ultimately, be a potential means of persuading mothers to engage in behavioral changes that could reduce their disease risk. To better determine the potential for women to engage in risk-reducing lifestyle behaviors advocated for in the messages, we investigated several antecedents to behavior change (message satisfaction, acceptance and beliefs about the information, and behavioral intentions to adopt the guidance). Additionally, to ascertain the potential reach of this intervention approach, we explored women’s dissemination of and preferences for information via other social media platforms, allowing us to explore the potential for rapid diffusion via this intervention approach.

Results indicated that mommy blog readers who were exposed to (and specifically recalled) the seeded intervention message adapted from BCERP guidance had higher breast cancer risk information exposure scores and higher breast cancer risk and prevention information satisfaction and influence scores than those who did not see (or recall) them. These findings are consistent with previous theory and research on the influence of social networks and opinion leaders within them on health perceptions [14,19,32,45]. Thus, mommy bloggers may serve as important opinion leaders for some women. Moreover, mommy bloggers may be key to enhancing the messaging, delivery, and impact of environmental breast cancer risk information on mothers.

Our intervention involved both evidence-based and user-generated message development. As such, our targeted intervention demonstrated that future designers of breast cancer communication interventions can provide online opinion leaders such as mommy bloggers with health information adapted from evidence-based research from authoritative groups (eg, National Institutes of Health [NIH]). This may be especially important in better ensuring that information posted on blogs is accurate and credible given a recent study that showed that blogs are often less accurate than other online sources [12]. Our findings also show that it is important to include content generated by the user (blogger). Online opinion leaders can tailor more stylistic aspects of intervention messages and communicate them according to their readers’ needs, experiences, and preferences. Using established relationships between bloggers and their readers may provide a more organic and collaborative means of tailoring health-related messages compared with interventions where the message tailoring is conducted by the researchers alone (based on target audience member feedback and characteristics). Future studies should compare similar types of message-seeding strategies via established opinion leaders with more traditional message tailoring approaches to further assess their potential variant influence on health outcomes.

In addition, findings revealed that disseminating health messages through opinion leaders may influence the further dissemination and amplification of those messages, meaning that there is potential for rapid diffusion of information via social media interventions. Findings of the Tracx analysis indicated that initial mommy blog message posts were shared on a variety of social networking sites, including Facebook, Twitter, Instagram, and other blogs, with Instagram being the most widely used. However, data from the blog reader survey (RQ2) indicated that participants varied widely in terms of self-reported preferences for how they would like to receive environmental breast cancer risk information in the future. Overall, these findings suggest that disseminating health information through blogs may have an extensive reach. Information may be encountered by individuals in one social media platform and then shared with others across other (perhaps more preferred) social media. Our Tracx data on message reach showed that some form of the initial seeded intervention messages from the participating bloggers was shared well beyond their initial blog reader audience.

Moreover, this study found that reach, or rapid diffusion of information, extended beyond online communities and platforms to individuals’ personal networks. Our data showed that mommy bloggers’ posts spurred interaction about breast cancer risk among women and their daughters, specifically. This finding is an important reminder that health information encountered via social media is often shared in close relationships, which may reinforce the impact of the information on health behaviors. This finding is consistent with Rogers’ diffusion of innovation theory [14] and associated research that illustrates a 2-step flow of information from media to interpersonal conversations. Future research would benefit from the use of social network analysis to explore the spread of message dissemination among bloggers, their readers, and other online or face-to-face social network members.

The findings also prompt questions about how to best prepare women who use blogs and other social media for conversations with their daughters about environmental breast cancer risk. Communication competence is particularly of concern when mothers talk to their daughters about risk-related topics since these conversations can increase psychological and physiological distress for daughters [3,50]. Other factors, including culture, relational history, and age or maturity, make these conversations even more complex to navigate. Future studies should consider messages that incorporate tailored guidance for engaging in family conversations about breast cancer risk.

Moreover, the findings indicated that the intervention message had a modest impact on key study measures of exposure, satisfaction with the message, intentions to act on the information, and likelihood of sharing the information with others. One intervening variable was participant’s recall of the message. Although we know that individuals who recalled the message were more exposed and satisfied with them, and they had stronger intentions to act on the information than the comparison group, it is unknown whether they were recalled from the original blogger post, comments from online or face-to-face social network members, or another social networking site (eg, Facebook and Instagram). Future researchers should take this into account when attempting similar types of seeded messaging strategies. Although researchers can track where information has been reposted or replied to using programs such as Tracx, it is often difficult to assess (outside of self-reports) where people encountered specific intervention messages within the social media landscape or how these transfer to interpersonal conversations. In addition, since 42% of women in the comparison group had a family history of breast cancer, it is likely that these individuals had a keen interest in breast cancer prevention and could have been prone to seek this information on blogs (increasing the chance for contamination between the treatment and comparison groups).

The findings also suggest that Instagram was the most popular other social media platform for blog readers. This is likely because of Instagram’s ability to conveniently share or obtain breast cancer information on a variety of other social media channels (such as Facebook and Twitter). Future research should examine how Instagram (and similar platforms) may enhance the reach and impact of future interventions that attempt to seed similar online opinion leaders with evidence-based breast cancer and environmental risk and prevention messages.

There are a number of limitations in this study. First, the study relied on a convenience sample of participants using a quasi-experimental design as opposed to a randomized treatment or control group study. One of the reasons for this was the desire to work with naturally occurring bloggers and their established online social networks of readers. However, the lack of randomized groups limits the generalizability of claims regarding the efficacy of the seeded mommy blogger intervention used in this study.

Additionally, the bloggers and blog readers tended to be highly educated overall. Less than 10% of the intervention group or comparison group members had a high school education or less. The researchers are in the process of analyzing qualitative interview data from a subset of ethnic minority and lower socioeconomic status respondents who participated in this study to assess how intervention messages could be tailored in more culturally sensitive and educationally appropriate ways in future research.

Yet, the findings provide insights into the value of this approach while highlighting consideration for future research. One future direction would be to systematically assess what factors are associated with greater likelihood of recall among participants in this type of intervention. The education level was controlled in this study, but other factors associated with education, such as health (or electronic health) literacy, could influence message recall. To explore the impact of such factors on participant recall, studies might employ interviews and/or other qualitative methods to see how user-centered design can be integrated with scientifically accurate information to develop more memorable messages.

In terms of other limitations, blog readers typically follow more than one blog, and this might have led to contamination between the intervention and comparison groups. However, we attempted to correct this by asking readers to report up to 5 blogs they visited most frequently in the past year. This allowed us to discover individuals in the comparison group who saw the intervention message. Furthermore, we were limited by the number of survey items we could reasonably include, which contributed to not being able to use larger multidimensional measures of the key variables of interest. In future research, we hope to capture more nuanced aspects of complex variables, such as behavioral intentions to act on environmental breast cancer guidance, as well as finding ways to better distinguish between people who actively disseminate intervention messages and those who are more passive recipients of these messages (ie, lurkers).

Finally, the use of longitudinal research designs is important when assessing health knowledge and behavior change that may result from a social media intervention such as the one reported here. Given that the reader survey was administered over a 2-month period following the start of the mommy blogger intervention, it is difficult to know about the long-term effects of exposure to these types of messages. Future studies need to find creative ways to measure variables longitudinally in an environment that is dynamic in terms of online network membership and the stability of specific social media channels (eg, social media platforms may decline in popularity over time and users may shift to newer platforms). This presents numerous challenges in terms of deciding the best channel(s) for health intervention messages, including those regarding environmental breast cancer risk. Moreover, future researchers should consider assessing mommy bloggers’ satisfaction regarding their participation in terms of serving as opinion leaders in similar interventions.

The study results showed promise for the utilization of online opinion leaders such as mommy bloggers as influential channels for the dissemination of both evidence-based and user-generated environmental breast cancer risk messages. Moreover, this study shed light on how blog readers share environmental breast cancer risk and prevention messages across different social media platforms and the preferred channels for receiving this type of information. Results also revealed the potential reach of disseminating health risk information via bloggers. Mommy bloggers may be especially primed to disseminate health risk information geared toward mothers, and this channel may effectively serve as a catalyst for mother-daughter communication about breast cancer risk reduction. Mommy bloggers may also aid interventionists in enhancing the messaging, delivery, and impact of environmental breast cancer risk information.