Try out PMC Labs and tell us what you think. Learn More. Despite the introduction of the human papillomavirus HPV vaccination as a preventive measure in for cervical and other cancers, uptake rates remain suboptimal, resulting in preventable cancer mortality. Little is known regarding attitudes related to HPV vaccination on Reddit a popular news aggregation site and online communityparticularly related to cancer risk and sexual activity.
Examining HPV vaccine—related messages on Reddit may provide insight into how HPV discussions are characterized on forums online and influence decision making related to vaccination. We observed how the HPV vaccine is characterized on Reddit over time and by user gender. Specifically, this study aimed to determine 1 if Reddit messages are more related to cancer risks or sexual behavior and 2 what other HPV vaccine—related discussion topics appear on Reddit. We gathered all public Reddit comments from January to September We manually annotated messages to generate keywords and identify salient themes.
We then measured the similarity between each comment and lists of keywords associated with sexual behavior and cancer risk using Latent Semantic Analysis LSA. We analyzed 22, messages containing the strings hpv or human papillomavirus and vaccin.
LDA analyses demonstrated that although topics related to cancer risk and sexual activity were both frequently discussed The most frequently discussed topic was politics associated with the vaccine Reddit discourse on HPV vaccine encompasses a broad range of topics among men and women, with HPV political debates and cancer risk making up the plurality of the discussion.
Our findings demonstrated that women and men both discussed HPV, highlighting that Reddit users do not perceive HPV as an issue that only pertains to women. Given the increasing use of social media as a source of health information, these can inform the development of targeted online health communication strategies to promote HPV vaccination to young adult users of Reddit. Analyzing online discussions on Reddit can inform health communication efforts by identifying relevant, important HPV-related topics among online communities.
Long-lasting infections with high-risk human papillomaviruses HPVs can cause cancer in parts of the body where HPV infects cells, such as in the cervix, oropharynx, anus, rectum, penis, vagina, and vulva. Virtually all cervical cancers are caused by HPV. HPV vaccination acceptance is a critical public health issue as low completion rates of the vaccine series place adolescents and young adults at risk for HPV-associated infection and cancers. The multiple factors that influence vaccine acceptance have been examined on traditional mass media and social media, including the understudied platform, Reddit.
This study is the first to examine HPV discourse on Reddit, which provides insight about attitudes of HPV vaccination among a unique population that may not be readily accessible in traditional data surveillance methods [ 1 ].
Our findings build upon the literature examining attitudes toward HPV vaccination online and in the media. Our goals were to assess whether discussions on Reddit reflected the competing narratives cancer risk vs sexual promiscuity described in the broader discourse [ 2 - 5 ] and, secondly, to document and describe the full range of HPV vaccine—related topics discussed on Reddit.
The vaccine series is safe and widely effective when taken before the onset of sexual activity and potential HPV exposure. However, national vaccination rates remain low, with only Factors contributing to lagging vaccination rates include parental concerns about vaccine safety [ 8 ], low confidence in adolescent vaccination [ 9 ], lack of provider recommendation [ 10 ], general lack of knowledge about the vaccine [ 11 ], and concerns about adolescent sexual behavior [ 1213 ].
In particular, as HPV is sexually transmitted, some parents fear that vaccination will give for adolescents to engage in early or risky sexual activity [ 2 ] this has been refuted by prior research [ 214 ]. Owing to the stigma associated with sexually transmitted infections STIsparents and providers have faced challenges addressing the sexual nature of HPV [ 3 ].
This stigma is exacerbated by the fact that the initial recommendation of HPV vaccination was for girls only. This enduring, gendered narrative has contributed to low vaccine uptake and opportunity loss for cancer prevention among men, who are increasingly affected by HPV-related anal, penile, and oropharyngeal cancers [ 18 ].
The media are influential in relaying HPV-related cancer risk communication and contributing to fears of adolescent sexual behavior, including promiscuity concerns. Although HPV vaccination has been studied on other media, social media may have a particularly strong impact on public perception of HPV vaccination risks. Furthermore, the open nature of social media provides a critical opportunity to investigate personal attitudes and beliefs regarding HPV vaccination.
Thus, an understanding of the online discourse regarding HPV vaccination can aid public health communicators in their efforts to address public misconceptions. Reddit is a popular online forum that allows users to post, share, and rank content through a voting system. Reddit has million monthly visitors, nominating it as the fifth most visited website in the United States [ 2324 ].
Although HPV has been studied on social media platforms such as Twitter, YouTube, and Pinterest [ 25 - 27 ], to our knowledge, no published study has examined Reddit content related to HPV vaccination. Reddit data capture attitudes and trends that are not readily accessible in traditional data surveillance methods, as highlighted in studies that used Reddit data [ 2829 ].
In a survey of the Reddit community [ 31 ], Of these, Thus, an analysis of Reddit provides insight into the male perspective of HPV vaccination on social media, an understudied area in the literature where women have been the focus. This study was the first to utilize Reddit data to gain a better understanding of online public discussions of the HPV vaccine, including determining whether online discussions mirror research and media coverage. Furthermore, to the extent that those two topics may not be representative of the total HPV-related discourse on Reddit, we conducted an additional topic analysis.
Our research questions RQs are as follows:.
Studying cancer risks, sexual activity, and other emerging topics from Reddit content would provide greater insight into extant online discussions about HPV vaccine, which can inform concerted, tailored health communication efforts to promote HPV vaccination and improve uptake rates. We used Reddit as our main data source. Unlike microblogging social media platforms such as Twitter, Reddit does not limit message length, allowing users to express their opinions in depth.
Reddit also has a strong community-based moderation culture; repetitive messages or unrelated messages will often be removed by moderators of each subreddit. Therefore, Reddit comments are a promising data source for understanding how a segment of the online community perceives the risks of HPV and the risks and benefits of the HPV vaccine.
We downloaded all recent Reddit comments from January 1,to September 30,using a platform which allows researchers to collect and share complete Reddit datasets for research purposes [ 33 ]. At the time of analysis inthe most up-to-date data were culled, resulting in our use of data from to Our aim was to determine whether HPV-related messages discussed sexual behavior or cancer risk more often. First, 2 annotators YL and AJ manually annotated 50 messages and selected an initial set of keywords associated with both topic areas.
The same annotators then annotated another messages, in rounds of 50 each, adjusting the keywords and refining coding techniques. Through this iterative process, we created a codebook to identify messages as either pertaining to cancer risk, sexual activity, or other Table 1.
Next, we employed Latent Semantic Analysis LSA [ 35 ], a commonly used technique in natural language processing, to measure the semantic similarity between each Reddit message and the keyword lists. We next applied term frequency-inverse document frequency weighting to the corpus. Finally, consistent with the past literature, we retained dimensions 2 to when computing the Singular Value Decomposition underlying LSA. We used the underlying LSA space to measure the cosine similarity between each Reddit post and each keyword list and calculated the average similarity score per month see Multimedia Appendix 1.
In addition, we developed a classifier to assess the gender of the user posting each message.
This tool helped us understand the overall difference between male and female user discussions related to the HPV vaccine. The classifier works by identifying gender-indicating keywords and expressions included in Reddit messages.
We manually annotated over messages to test the accuracy of the classifier. We also developed a classifier to assess the age of users into 7 age 10 to 18, 18 to 24, 25 to 34, 35 to 44, 45 to 54, 55 to 64, and 65 and older consistent with Reddit surveys [ 31 ].
Nevertheless, the current accuracy is higher than the random baseline of 7 This classifier, which is being developed, cannot be used to reach a definite conclusion of the age groups. LDA ass each word token to one of these topics, allowing one to summarize the content of each Reddit post. After examining models with 20 and 50 topics, we determined that a topic model best captured the variety of discussion subjects with minimal redundancy.
For each month, we calculated how many word tokens belonged to each topic. The proportional topic weight of each year was calculated by the following equation:. Mitigating concerns about behavior by malicious actors, such as bots, we found that no two messages in our dataset are exactly the same, a common indicator of bot behavior [ 37 ]. The of messages varied by year and increased over time, from messages in to a peak of messages in Figure 1.
In manual annotation, it was clear that messages describing cancer risk were more identifiable than messages discussing HPV-related sexual behavior. Cancer risk messages tended to focus on specific themes, including the relationship between HPV infection and cancer incidence especially related to specific HPV strainsand on HPV vaccination as a resource to prevent future cancer incidence. Messages about sexual behaviors were more varied. The widespread use of sarcasm and irony on Reddit also made it difficult to know the meaning of some messages out of context.
Many of the messages we encountered incorporated the moral foundation keywords, but only to refute the idea that HPV vaccine promotes promiscuity.
To capture the complexity of this topic, we broadened our coding scheme to include any discussion of sexual activity and HPV vaccination and were able to identify a wider range of subjects including safe sex practices, personal stories, and debates over sexual risk. The LSA analysis showed that cancer is ificantly more discussed than sexual activity Table 3.
However, the average monthly Reddit message discussed neither cancer nor sexuality cosine similarity values were 0. These low similarity scores indicate that other topics must exist in the corpus that are neither about cancer nor sexual behavior. Furthermore, we observed a decrease in average similarity to both cancer and sexuality over time, indicating that other topics of discourse may have emerged within these forums.
In general, we did not notice a ificant difference between genders in discussions of cancer and sexual activity all P values were greater than. In our close reading of messages for manual annotation, we recognized that although messages included keywords related to cancer risk or sexual activity, there were additional topics that extended beyond the scope of either topic Table 4. Some of these conversations were narrowly focused on HPV vaccination, for instance, debates over whether vaccinating the entire population was a cost-effective prevention method or discussions of vaccine efficacy related to particular strains of HPV.
Other conversations were focused on sexual activity and health, in general. We observed a subset of conversations that detailed personal experiences with STIs and described the various steps individuals had taken to avoid all types of STIs eg, condom use, HPV vaccination, and regular STI testing. Another major topic was related to circumcision, as some users felt that primary prevention measures such as HPV vaccination reduced the need to circumcise as circumcision is often cited as a method to reduce STI infection.
Finally, another subset of conversations was focused on broader political and philosophical discussions that sometimes used HPV vaccination as a talking point. For instance, political discussions of the role of government sometimes questioned vaccine mandates as infringing on parental rights as part of a larger justification for libertarianism.
Alternatively, users would discuss sexual education, access to contraceptives, and HPV vaccination as talking points in discussions of abortion rights Table 4. Although these conversations were not specifically focused on HPV vaccination, we believed they reflect the broader discourse on the topic and were an important area of study.
In addition to the diversity in topics, it appears users were turning to Reddit for a variety of reasons: some were posing questions and were looking for answers; others seemed to want to debate; some just wanted to discuss topical issues in the news; and still others seemed to want to make jokes.
Messages ranged from one-word responses to posts a few thousand words long. Some were based on personal experiences and anecdotes, and others were based on facts and statistics, often linking to cited research. The understanding gained from reading HPV vaccine—related messages led us to our second research question, as we realized we needed to explore the full range of topics that were being discussed on Reddit.
The most widely discussed topic was HPV-related political debate Cancer was the second most widely discussed This was followed by sexual activity and preventive behaviors