Public Awareness of the Fencing Response as an Indicator of Traumatic Brain Injury: Quantitative Study of Twitter and Wikipedia Data

Background Traumatic brain injury (TBI) is a disruption in normal brain function caused by an impact of external forces on the head. TBI affects millions of individuals per year, many potentially experiencing chronic symptoms and long-term disability, creating a public health crisis and an economic burden on society. The public discourse around sport-related TBIs has increased in recent decades; however, recognition of a possible TBI remains a challenge. The fencing response is an immediate posturing of the limbs, which can occur in individuals who sustain a TBI and can be used as an overt indicator of TBI. Typically, an individual demonstrating the fencing response exhibits extension in 1 arm and flexion in the contralateral arm immediately upon impact to the head; variations of forearm posturing among each limb have been observed. The tonic posturing is retained for several seconds, sufficient for observation and recognition of a TBI. Since the publication of the original peer-reviewed article on the fencing response, there have been efforts to raise awareness of the fencing response as a visible sign of TBI through publicly available web-based platforms, such as Twitter and Wikipedia. Objective We aimed to quantify trends that demonstrate levels of public discussion and awareness of the fencing response over time using data from Twitter and Wikipedia. Methods Raw Twitter data from January 1, 2010, to December 31, 2019, were accessed using the RStudio package academictwitteR and queried for the text “fencing response.” Data for page views of the Fencing Response Wikipedia article from January 1, 2010, to December 31, 2019, were accessed using the RStudio packages wikipediatrend and pageviews. Data were clustered by weekday, month, half-year (to represent the American football season vs off-season), and year to identify trends over time. Seasonal regression analysis was used to analyze the relationship between the number of fencing response tweets and page views and month of the year. Results Twitter mentions of the fencing response and Wikipedia page views increased overall from 2010 to 2019, with hundreds of tweets and hundreds of thousands of Wikipedia page views per year. Twitter mentions peaked during the American football season, especially on and following game days. Wikipedia page views did not demonstrate a clear weekday or seasonal pattern, but instead had multiple peaks across various months and years, with January having more page views than May. Conclusions Here, we demonstrated increased awareness of the fencing response over time using public data from Twitter and Wikipedia. Effective scientific communication through free public platforms can help spread awareness of clinical indicators of TBI, such as the fencing response. Greater awareness of the fencing response as a “red-flag” sign of TBI among coaches, athletic trainers, and sports organizations can help with medical care and return-to-play decisions.


Traumatic Brain Injury
Traumatic brain injury (TBI) is broadly defined as a disruption in normal brain function caused by an impact of external forces on the head or skull. TBI is both a public health crisis and an economic burden. In 2013, there were approximately 2.5 million TBI-related emergency department (ED) visits, approximately 282,000 TBI-related hospitalizations, and approximately 56,000 TBI-related deaths in the United States [1]. However, these numbers are likely to be underestimated as many individuals do not seek medical attention after a TBI. In the United States, children (aged 0-4 years), adolescents (aged 15-19 years), and older adults (aged >75 years) have the highest rates of TBI-related ED visits and hospitalizations [2]. Accurate on-site detection of TBI can guide patients to health care facilities. The prevalence of long-term disability associated with TBI has been estimated at 1.1% (3.17 million people) among the civilian population of the United States [3]. Nationwide, TBI is estimated to be responsible for approximately US $48 billion to US $76 billion in total costs, consisting mostly of indirect costs from lost productivity and absenteeism [4]. Early and accurate detection may reduce the health care and economic burden of TBI.
The most common types of TBI occur after rotational or acceleration/deceleration forces displace the brain within the skull without penetrating the skull (diffuse TBI) [5,6]. The pathophysiological damage can be widespread and may vary by severity of the impact forces (ie, mild, moderate, and severe), resulting in an array of persistent clinical symptoms. Symptoms can be broadly categorized as cognitive, somatic, sensory, motor, and emotional dysfunction, and each individual who sustains a TBI will likely experience a distinct range of clinical symptoms, symptom onset, and symptom resolution [2]. However, for most individuals who sustain a TBI, clinical symptoms resolve within 1-10 days after injury [7]. Persistent symptoms may linger for some individuals, particularly those who sustain repeated TBIs, for months to years after the injury, including increased risk for psychiatric disorders, drug abuse, and suicide [2,8,9].
Perhaps due to the potential for long-term symptoms and disability, considerable public interest focuses on sport-related TBI among adolescents (<19 years) [10,11]. The most common sport and recreational activities associated with TBI-related ED visits in adolescents are bicycling, American football, basketball, soccer, and playground activities [2]. From 2001 to 2009, the rate of adolescent ED visits related to a TBI associated with sports or recreational activities increased 62% [2]. While the rate of TBI-related ED visits increased, the rate of TBI-related hospitalizations and death remained stable over the same time. One reason for these trends could be increased awareness of TBI through public health campaigns, education, and sports media coverage, which could encourage individuals to seek medical treatment.
Recognition of a potential TBI and removing an athlete from play are the first steps to provide necessary medical care in the event of a TBI. However, mild to moderate diffuse TBI may not immediately present with overt clinical symptoms, putting individuals at risk for additional injuries if not removed from play. Current diagnostic tools for TBI vary in their accuracy, and recognition of a potential injury remains a challenge, prompting the need for additional screening criteria at or near the time of injury [12,13].

Fencing Response
The fencing response is an immediate tonic posturing of the limbs, similar to the asymmetric tonic neck reflex in infants, where extension and flexion of opposite arms occur despite body position or gravity. Upon impact to the head, an individual demonstrating the fencing response immediately exhibits extension in 1 arm and flexion in the contralateral arm while falling to the ground; different manifestations have been observed between limbs. Tonic posturing is then retained for several seconds and readily observable by onlookers (eg, coaches, trainers, parents, and teammates). In 2009, Hosseini and Lifshitz [14] published their experimental and clinical research on the relationship between the fencing response and TBI. In the review of videos of people (including athletes) subjected to a head impact, they found that 66% of the participants demonstrated the fencing response upon impact, regardless of the side of the impact [14]. The average duration of tonic arm posturing was approximately 6 seconds.
The fencing response was additionally observed in adult male rats subjected to brain injury forces delivered by midline fluid percussion. However, the fencing response was observed only with brain injury forces of moderate magnitude and not mild magnitude or in uninjured sham animals [14]. Histopathological analysis of the lateral vestibular nucleus-the anatomical structure involved in the asymmetric tonic neck reflex in infants-further demonstrated transient neurochemical activation with injury [14]. The proximity of the lateral vestibular nucleus to the cerebellar peduncles makes it vulnerable to rotational mechanical forces that cause neuronal depolarization and elicit a neuromotor response, distinct from convulsion, associated with TBI.
The fencing response can thus be used as a visible indicator of TBI and may assist with screening and decisions regarding medical care [15][16][17]. In order to reach a broad audience, our research team created a Wikipedia page on the subject shortly after the publication. Wikipedia is widely used as a resource for medical information as it is easily accessible on the internet [18][19][20]. By accessing the Fencing Response Wikipedia page, health care professionals and the general public could educate themselves about the fencing response and link to the primary publication for more information [18,21,22]. Wikipedia pages can be updated as new information about the fencing response is discovered [20,23]. Additionally, the research team was active on Twitter shortly after the publication to demonstrate occurrences of the fencing response in professional sports and share links to both the Wikipedia page and original scientific publication. Twitter has hundreds of millions of daily users and has been shown to be an effective platform for education and spreading public health awareness [24,25]. The objective of this study was to quantify trends over time of the awareness of the fencing response using data extracted from Twitter and Wikipedia.

Twitter
First, we applied for academic research access for Twitter's Academic Research Product Track v2 application programming interfaces (APIs) [26]. Once approved, raw data from Twitter were accessed using the RStudio package academictwitteR [27]. Approved academic research access was required to query the full Twitter archive. academictwitteR was designed for querying the Twitter Academic Research Product Track v2 API and was chosen for straightforward data collection and management. Tweets were queried for the text fencing response between January 1, 2010, and December 31, 2019. Between 2010 and 2019, a total of 6176 tweets contained the words fencing and response. These included both primary tweets and retweets, but not "liked" tweets. All tweets were read and verified for relevance to TBI. Unverified tweets contained the words fencing and response, but not in reference to TBI. Excluded tweets referenced, for example, the USA Fencing team's response to misconduct allegations. A total of 2550 tweets were excluded, and 3626 tweets were included in the analysis. The number of tweets was analyzed as a function of time, including the day of the week, month, 6 months (September to February and March to August to represent the American football season vs off-season), and year. We performed a seasonal regression analysis in Microsoft Excel to further examine the relationship between the number of fencing response tweets and month of the year. After data were visualized, we identified peaks at certain months and years (ie, December 2017). A rereview of the Twitter raw data during the peaks was used to identify notable events that initiated the discussion on Twitter.

Wikipedia
Raw data from Wikipedia were accessed using the RStudio packages wikipediatrend and pageviews [28,29]. Wikipediatrend and pageviews were developed in tandem to easily access daily page view data from "Wikimedia" sites and were chosen for feasibility. Daily page views for the Fencing Response Wikipedia article [30] were accessed between January 1, 2010, and December 31, 2019, for analysis. The number of page views was analyzed as a function of time, including day of the week, month, 6 months (September to February and March to August to represent the American football season vs off-season), and year. We performed a seasonal regression analysis in Microsoft Excel to further examine the relationship between Wikipedia page views and month of the year, using the month of May as a reference. Wikipedia page views on specific days around the notable events identified by Twitter are reported.

Ethical Considerations
Prior to the start of the study, we submitted a project proposal to the University of Arizona's institutional review board. The institutional review board determined that the study (STUDY 00000842) did not involve human subjects research as defined by Department of Health and Human Services and Food and Drug Administration regulations. Public Twitter data (ie, tweets from nonprivate Twitter accounts) posted over the last 7 days are available to any user with a Twitter account that registers on the Twitter Developer Platform. Further, a developer account can apply to access the academic research product track to gain access to the full archive of tweets dating back to March 2006. With academic approval from Twitter for the current research project, an authentication key provided unrestricted access to the full archive of tweets.

Twitter Mentions of the Fencing Response Increased Over Time and Have Patterns of Seasonality
The annual number of tweets mentioning the fencing response increased overall from 2010 to 2019, with notable peaks in 2013 and 2017 ( Figure 1A). The highest number of tweets occurred on Sunday followed by Monday, and we observed a decrease as the week went on until Friday and Saturday ( Figure 1B). The total number of tweets varied by month, with most tweets occurring in the latter half of the calendar year ( Figure 1C). We chose to divide the years into two 6-month periods roughly representing the American football season (September to February) and its off-season (March to August). There were more than 3 times as many tweets mentioning the fencing response between September and February compared to the months from March to August ( Figure 1D). A seasonal regression analysis further examined the relationship between the number of tweets and time (month of the year). The model was a significant predictor of the monthly number of tweets (F 1,12 =2.454, P=.007) and explained 22.1% of variation in the monthly number of tweets (R 2 =0.221). Month of the year had a significant effect on the number of tweets (P<.001) with December and January and having a significantly higher number of tweets than May (P=.002, P=.008, respectively).
In examining each year from 2010 to 2019 separately, a seasonal pattern was again observed, with most tweets occurring between September and February ( Figure 2). During those months, tweets mostly occurred on Sundays and Mondays (Figure 3). This pattern was not observed during the months of March to August. Specific peaks in the number of Twitter mentions were reviewed to identify specific days with notable televised injury events that generated discussion on Twitter (Table 1). The years were divided into two 6-month periods roughly representing the American football season (September-February) and its offseason (March-August). There were more than 3 times as many tweets that mentioned the fencing response during the months of September-February compared to March-August.

Page Views of the Fencing Response Wikipedia Article Increased Over Time and Have Patterns of Seasonality
The annual number of page views of the Fencing Response Wikipedia article increased overall from 2010 to 2019 ( Figure  4A). Page views by day of the week varied with no clear pattern (eg, weekend vs weekday; Figure 4B), and monthly page views varied with January representing the peak month ( Figure 4C). We observed slight seasonal variation, with more page views occurring between September and February ( Figure 4D). A seasonal regression analysis further examined the relationship between Wikipedia fencing response page views and time (month of the year). The model was a significant predictor of the monthly number of page views (F 1,12 =3.57, P<.001) and explained 29.2% of variation in the monthly number of page views (R 2 =0.292). Month of the year had a significant effect on the number of Wikipedia page views (P<.001) with January having significantly higher page views than May (P=.009). While article page views increased overall from 2010 to 2019, there were multiple peaks across combinations of months and years ( Figure 5). Individual peaks were linked with notable injury occurrences in televised professional sports (Table 1).

Discussion
Research published in peer-reviewed journals serves as the foundation of society's scientific knowledge, and still the content remains out of reach to the public. Publicly available platforms, like Twitter and Wikipedia, vary in quality and have the ability to reach a broad audience. The 2009 peer-reviewed article on the fencing response published in the journal Medicine & Science in Sports & Exercise has been viewed approximately 320 times in the 5 years prior to the writing of this paper [14].
The Fencing Response Wikipedia article, on the other hand, has been viewed over 1 million times over the same period. Therefore, if an individual is aware of the fencing response, especially outside of the brain injury field, in all likelihood they learned about it through a publicly available platform rather than the original scientific paper.
Twitter mentions of the fencing response and page views of the FencingResponse Wikipedia article increased overall from 2010 to 2019, following the publication of the original peer-reviewed article that described the fencing response. Twitter mentions peaked during the American football season (September to February), especially on Sundays and Mondays and December and January overall had a higher number of Twitter mentions than May. This suggests that more discussion of the fencing response occurred on and following the National Football League (NFL) gameday. Wikipedia article page views did not appear to have peaks corresponding to specific days of the week, and we did not observe differences in the number of page views when dividing the year in half (September to February vs March to August). However, we observed seasonality across months, where the number of page views in January was significantly higher than the number of page views in May. Furthermore, the number of Wikipedia page views was orders of magnitude greater than the number of tweets.
Specific peaks in Twitter mentions were identified in January 2013 and December 2017. These and other minor peaks were associated with notable events that generated discussion on social media and also led to increased page views on the Wikipedia article (Table 1). For example, the January 2013 peak was associated with an NFL game between the New England Patriots and Baltimore Ravens on January 20, 2013, in which Patriots running back Stevan Ridley had a head injury with loss of consciousness. An article was subsequently published on the popular sports website Bleacher Report entitled, "Stevan Ridley's concussion: biomechanics of his injury, 'fencing response'" [31]. The day prior to the televised injury, there were zero tweets that mentioned the fencing response. On the day of the injury and 3 days following the injury, there were 284 tweets that mentioned the fencing response (Table 1). Wikipedia page views increased approximately 5.5 times on the 3 days following the injury ( Table 1).
The December 2017 peak was associated with an NFL game between the Houston Texans and San Francisco 49ers on December 10, 2017, in which Texans quarterback Tom Savage sustained an apparent TBI after being tackled by a 49ers defender. Savage returned to play following a brief evaluation by medical staff. However, he was later removed from the game after a second evaluation revealed signs of a TBI. The day prior to the injury, there was 1 tweet that mentioned the fencing response. Whereas, on the day of the injury and 3 days following the injury, there were 392 tweets that mentioned the fencing response (Table 1). Additionally, Wikipedia page views increased approximately 106 times on the 3 days following the injury (Table 1). These examples demonstrate more discussion and self-education on the fencing response, and head injury, on and following American football game days.
Of note, the NFL added the fencing response (tonic posturing) as a sign of potential concussion to their Concussion Diagnosis and Management Protocol in 2017 [32]. American football is the most popular spectator sport in the United States, and recognition of the fencing response as a "red-flag" sign of TBI by the NFL could further increase awareness among large audiences [33]. As role models in the medical management of athletes, the actions of the NFL can influence decisions in collegiate, high school, club, and recreational sports.

Limitations
One limitation of the Twitter data in this report is the restriction to primary tweets and retweets, without analysis of "likes." Further analyses, including visualization of a Twitter conversation with Treeverse, may more completely characterize the Twitter conversation by hierarchical indexing of primary tweets, retweets, and "liked" tweets. However, some of these analyses require an index tweet to drive the conversation, whereas most discourse on the fencing response originates from observed experience, not a single tweet. It should also be noted that Twitter and Wikipedia are available worldwide to anyone with internet access. Thus, the patterns reported here may be explained by differing usage rates of these platforms in countries across the globe and by the popularity of American football. The United States has, by far, more Twitter users than any other country at approximately 77 million. Following are Japan and India with approximately 59 million and 24 million users, respectively [34]. Twitter's user base in other countries is comparatively small. Wikipedia, on the other hand, while still more popular in the United States than any other country, is used more broadly [35]. This could explain why Twitter mentions of the fencing response appear to occur mostly during the American football season, while Fencing Response Wikipedia page views do not demonstrate the same seasonal pattern. Additionally, we limited our data collection to Twitter and Wikipedia for the accessibility of APIs to extract data in the public domain; other platforms exist to demonstrate and examine patterns of interest such as Google Trends, YouTube, Instagram, Facebook, and LinkedIn.

Conclusions
In this study, data from Twitter and Wikipedia were used to demonstrate an overall increase in public discussion and awareness of the fencing response as an indicator of TBI over time. The results show weekly and seasonal patterns of increased discussion that align roughly with the American football season. Peaks in Twitter mentions and Wikipedia page views represented national-level events that created public discourse about the fencing response. Public platforms such as Twitter and Wikipedia can play an effective role in science communication and greater awareness of the fencing response among coaches, athletic trainers, and sports organizations has the potential to help with "return-to-play" and other medical care decisions after a potential TBI.