Online Discussion on #KidneyStones: A Longitudinal Assessment of Activity, Users and Content

Abstract

Introduction:
Twitter is a popular microblogging platform for the rapid dissemination of information and reciprocal exchange in the urological field. We aimed to assess the activity, users and content of the online discussion, #KidneyStones, on Twitter.

Methods:
We investigated the Symplur Signals analytics tool for Twitter data distributed via the #KidneyStones hashtag over a one year period. Activity analysis reflected overall activity and tweet enhancements. We assessed users' geolocations and performed an influencer analysis. Content analysis included the most frequently used words, tweet sentiment and shares for top tweets.

Results:
3,426 users generated over 10,333 tweets, which were frequently accompanied by links (49%), mentions (30%) and photos (13%). Users came from 106 countries across the globe and were most frequently from North America (63%) and Europe (16%). Individual and organisational healthcare professionals made up 56% of the influencers of the Twitter discussion on #KidneyStones. Besides the words 'kidney' (used 4,045 times) and 'stones' (3,335), 'pain' (1,233), 'urine' (1,158), and 'risk' (1,023) were the most frequently used words. 56% of tweets had a positive sentiment. The median (range) number of shares was 85 (62-587) for the top 10 links, 45.5 (17-94) for the top 10 photos, and 44 (22-95) for the top 10 retweets.

Conclusion:
The rapidly growing Twitter discussion on #KidneyStones engaged multiple stakeholders in the healthcare sector on a global scale and reached both professionals and laypeople. When used effectively and responsibly, the Twitter platform could improve prevention and medical care of kidney stone patients.

Full text

RESEARCH ARTICLE
Online Discussion on #KidneyStones: A
Longitudinal Assessment of Activity, Users
and Content
Johannes Salem
1☯
*, Hendrik Borgmann
2☯
, Matthew Bultitude
3
, Hans-Martin Fritsche
4
,
Axel Haferkamp
2
, Axel Heidenreich
1
, Arkadiusz Miernik
5
, Andreas Neisius
2
,
Thomas Knoll
6
, Christian Thomas
2
, Igor Tsaur
2
1Department of Urology, University Hospital, Cologne, Germany, 2Department of Urology, University of
Medicine, Mainz, Germany, 3Stone Unit, Guy's and St. Thomas' NHS Foundation Trust, London, United
Kingdom, 4Department of Urology, Caritas St Josef Hospital, University of Regensburg, Regensburg,
Germany, 5Department of Urology, University Medical Center, Freiburg, Germany, 6Department of
Urology, Klinikum Sindelfingen-Böblingen, Sindelfingen, Germany
☯These authors contributed equally to this work.
*j.salem@gesru.de
Abstract
Introduction
Twitter is a popular microblogging platform for the rapid dissemination of information and
reciprocal exchange in the urological field. We aimed to assess the activity, users and con-
tent of the online discussion, #KidneyStones, on Twitter.
Methods
We investigated the Symplur Signals analytics tool for Twitter data distributed via the #Kid-
neyStones hashtag over a one year period. Activity analysis reflected overall activity and
tweet enhancements. We assessed users’geolocations and performed an influencer analy-
sis. Content analysis included the most frequently used words, tweet sentiment and shares
for top tweets.
Results
3,426 users generated over 10,333 tweets, which were frequently accompanied by links
(49%), mentions (30%) and photos (13%). Users came from 106 countries across the globe
and were most frequently from North America (63%) and Europe (16%). Individual and
organisational healthcare professionals made up 56% of the influencers of the Twitter dis-
cussion on #KidneyStones. Besides the words ‘kidney’(used 4,045 times) and ‘stones’
(3,335), ‘pain’(1,233), ‘urine’(1,158), and ‘risk’(1,023) were the most frequently used
words. 56% of tweets had a positive sentiment. The median (range) number of shares was
85 (62–587) for the top 10 links, 45.5 (17–94) for the top 10 photos, and 44 (22–95) for the
top 10 retweets.
PLOS ONE | DOI:10.1371/journal.pone.0160863 August 18, 2016 1/11
a11111
OPEN ACCESS
Citation: Salem J, Borgmann H, Bultitude M, Fritsche
H-M, Haferkamp A, Heidenreich A, et al. (2016)
Online Discussion on #KidneyStones:A Longitudinal
Assessment of Activity, Users and Content. PLoS
ONE 11(8): e0160863. doi:10.1371/journal.
pone.0160863
Editor: Jeff M Sands, Emory University Department
of Medicine, UNITED STATES
Received: April 10, 2016
Accepted: July 26, 2016
Published: August 18, 2016
Copyright: © 2016 Salem et al. This is an open
access article distributed under the terms of the
Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any
medium, provided the original author and source are
credited.
Data Availability Statement: The information
underlying this study is available from the Symplur
Signals database, and can be accessed under www.
symplur.com/signals with a fee-based account
subscribed for the hashtag #KidneyStones. The time
period was set from 1st October 2014 to 1st October
2015. We paid US$1,099 for a one month explorative
analysis.
Funding: The authors have no support or funding to
report.

Conclusion
The rapidly growing Twitter discussion on #KidneyStones engaged multiple stakeholders in
the healthcare sector on a global scale and reached both professionals and laypeople.
When used effectively and responsibly, the Twitter platform could improve prevention and
medical care of kidney stone patients.
Introduction
The microblogging social media platform, Twitter, enjoys increasing popularity in the health-
care sector. Currently, over 70% of urologists in Australia and New Zealand have a social
media presence, with Twitter being the second most commonly used form after LinkedIn,
which serves a completely different purpose [1]. Urologists using Twitter during the European
Association of Urology (EAU) and the American Urological Association (AUA) congresses
regarded it as beneficial for professional networking, disseminating information, research,
advocacy, and career development [2]. Impressively, 1,860 users generated 15,419 tweets in
total at the EAU14 and AUA14 congresses [3]. Notably, the Twitter-based International Urol-
ogy Journal Club, #urojc, has established a high-level academic discussion of urologic manu-
scripts [4]. In attempt to standardise the online discussion about urological care, a particular
structuring of the key urology-related hashtags has recently been proposed [5]. Interestingly,
the high technology field of endourology was the first urologic subspeciality assessed for Twit-
ter activity during the 2013 World Congress of Endourology [6]. Most recently, a Twitter dis-
cussion during the Third Meeting of the European Association of Urology Section of
Urolithiasis 2015 comprised 94 users contributing 446 tweets [7].
In slightly more than a decade, the prevalence of urolithiasis in the United States has
increased from 5.2% to 8.8% [8], having a substantial socioeconomic impact [9] and incre-
mentally affecting younger patients [10]. Since evidence has been provided for both highly
prevalent urologic conditions and also diseases with young patient age at onset evoking more
Twitter activity than their counterparts [11], a vibrant Twitter discussion on stone disease is
likely. Interestingly, in conditions with broad-based Twitter communities, such as breast can-
cer, patients have reported an increase in disease knowledge from participating in Twitter dis-
cussions [12].
In the current investigation, we aimed to assess the potential of Twitter to constitute a
potential platform for the dissemination of contemporary evidence on prevention, diagnosis
and treatment of stone disease. Hypothesising that a Twitter discussion on #KidneyStones
might appreciably involve both healthcare givers and laypeople, as well as encourage consider-
able global public awareness, we investigated the characteristics of its activity, users and
content.
Materials and Methods
The study was approved by the Ethics Commission of the Faculty of Medicine of the University
of Cologne. We performed an extensive analysis of activity, users and content of the online dis-
cussion on #KidneyStones on Twitter, using the Symplur Signals database. Symplur (www.
symplur.com) is a Twitter analysis website that maintains a database of healthcare-related
Twitter conversations. Symplur Signals (www.symplur.com/signals) is a fee-based research
analytics tool that promotes the understanding of healthcare as seen by patients, doctors and
other stakeholders with access to healthcare social media data points.
Online Discussion on #KidneyStones
PLOS ONE | DOI:10.1371/journal.pone.0160863 August 18, 2016 2/11
Competing Interests: The authors have declared
that no competing interests exist.

In October 2015, we searched the Symplur Signals database for analytic insights into the
online discussion on #KidneyStones for the time period 1st October 2014 to 1st October 2015.
The activity analysis comprised the assessment of overall tweet activity, tweet metrics, engage-
ment metrics and tweet language metrics. Overall tweet activity was recorded as the number of
tweets and users, and these were related to time periods. We performed a detailed analysis of
the tweet transcript (exact list of all tweets) to assess the issues inducing peak activities. The
tweet metrics analysis was performed by retrieving statistics about ratio and frequency of
retweets, tweets with links, tweets with photos, tweet replies and tweets where one or more
Twitter users were mentioned. Engagement metrics were retrieved by obtaining the number of
users who tweeted over a set period of time, grouped by the number of tweets sent. A tweet lan-
guage analysis illustrated the language used by active participants over a set period of time.
Language type was identified by a natural language processing algorithm directly provided by
the Twitter application programming interface.
User analysis included the cumulative user report, users’geolocations, and an influencer
analysis of the top influencers in the #KidneyStones discussion. Cumulative and new users
were recorded for monthly intervals. Cumulative users did not represent recurring users, but
were counted as a new user the first time they used the #KidneyStones hashtag and as a previ-
ous user in subsequent reporting periods, regardless of activity. The geolocation of users was
recorded when users sent tweets tagged with certain geolocation data. We analysed the top 100
contributors to the #KidneyStones discussion, as measured by number of tweets in the influen-
cer analysis. For this purpose, we performed a Twitter profile analysis and assigned these top
influencers to these healthcare categories, in line with the Symplur Signals healthcare category
definitions: physician; patient; healthcare professional; caregiver/advocate; researcher/aca-
demic; individual other healthcare; individual other non-healthcare; organisation provider;
organisation research/academic; organisation government; organisation advocate/support;
organisation pharma; organisation other healthcare; organisation other non-healthcare, and
spam [13].
We used the Symplur Signals tools for content analysis. The 100 most frequently used
words in tweets on #KidneyStones were analysed and counted. Since multiple hashtags are
often used within a single tweet, we used the hashtag network graph to analyse hashtags accom-
panying the #KidneyStones discussion and their relationships. The sentiment report analysed
tweets for positive and negative sentiment by a natural language processing algorithm. The
algorithm is based on two custom dictionaries, one for positive words and one for negative
words. Each word in the dictionaries has a weighting from one to five, with five being the high-
est. Finally, we investigated the most frequently shared links, photos and the most frequently
retweeted tweets. We performed statistical calculations using the Statistical Package for the
Social Sciences 22.0 software (SPSS Inc., Chicago, IL, USA). Values are described as median
and range.
Results
Table 1 shows overall activity for the #KidneyStones online discussion on Twitter for the time
period of one year. 3,426 users produced 10,806 tweets. Fig 1 portrays the weekly number of
tweets on #KidneyStones, which slightly increased over the investigated time period. The peak
tweet activity occurred during a strategic massive tweet activity of key influencers, evoking a
large amount of retweets (influencers: @virtualclinicng, 9th March 2015 and 11th March 2015,
41 tweets on kidney stones prevention leading to a peak of over 500 tweets in a week; @mayo-
clinic, 11th July 2015, 41 tweets on kidney stones prevention during a radio show leading to a
peak of over 400 tweets in a week).
Online Discussion on #KidneyStones
PLOS ONE | DOI:10.1371/journal.pone.0160863 August 18, 2016 3/11

Out of 10,333 total tweets, 5,013 (49%) were accompanied by links, 3,101 (30%) by men-
tions and 1,337 (13%) by photos. 2,441 (24%) were retweets and 229 (2%) were tweet replies.
2,798 users (82%) generated one tweet, 331 (10%) two, 244 (7%) three to nine, and 53 (2%) 10
or more tweets. 9,942 (96%) of tweets were in the English language.
Fig 2 demonstrates that the monthly number of users contributing to the #KidneyStones
online discussion on Twitter from October 2014 grew steadily, with a median of 262 (range
189–454) new users per month. The median number of active users contributing to the #Kid-
neyStones online discussion was 304.5 per month (range 227–545). Users came from 106 coun-
tries and from all continents around the globe (Fig 3). The S1 Table lists the location of users
according to country and continent. North American users were most active (63%), ahead of
Table 1. Overview of tweet activity for the #KidneyStones online discussion on Twitter over a time period of one year.
Metric Total Per Month Per Week Per Day Per Hour
Tweets 10,333 849 198 28.3 1.18
Tweets per user 3.02 0.248 0.0578 0.00826 0.000344
Users who tweeted 3,426 282 65.7 9.39 0.391
doi:10.1371/journal.pone.0160863.t001
Fig 1. Tweet activity for the #KidneyStones online discussion on Twitter during the one year period. The weekly numbers of
tweets are represented as columns.
doi:10.1371/journal.pone.0160863.g001
Online Discussion on #KidneyStones
PLOS ONE | DOI:10.1371/journal.pone.0160863 August 18, 2016 4/11

European users (16%) and Asian users (10%). The top 100 influencers in the #KidneyStones
online discussion on Twitter, according to the number of tweets posted in the study period,
and stratified by healthcare category, are shown in Fig 4. Individuals not involved in healthcare
(38%) and healthcare organisations (37%; organisations: provider, advocate/support, govern-
ment, other) were the main influencers in the discussion. There were no spam accounts among
the top 100 influencers.
A content analysis of the most frequently used words in the #KidneyStones online discus-
sion on Twitter is shown in Fig 5. Besides ‘kidney’(used 4,045 times) and ‘stones’(3,335),
Fig 2. Growth in number of users contributing to the #KidneyStones online discussion on Twitter.
doi:10.1371/journal.pone.0160863.g002
Online Discussion on #KidneyStones
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‘pain’(1,233), ‘urine’(1,158), and ‘risk’(1,023) were the top words. The S2 Table presents the
complete content analysis with the 100 most frequently used words in #KidneyStones tweets.
The largest thematic proportion of tweets focused on disease awareness and prevention (35 of
100 words). The sentiment analysis revealed that 56% of the tweets had a positive sentiment
and 44% had a negative sentiment. The median (range) number of shares for the top 10 links
was 85 (62–587) and 45.5 (17–94) for the top 10 photos. The top 10 retweets had a median of
44 (22–95) retweets. The #KidneyStones hashtag was often related to the #health, #renalcolic,
#renalcalculus and #kidney hashtags.
Discussion
We performed a longitudinal assessment of activity, users and content of the online discussion
on #KidneyStones, using the Symplur Signals health analytics database. Over the one year
period, Twitter activity was reflected by 10,806 tweets, which were frequently enhanced with
links and mentions, and were posted predominantly in English. Together, 3,426 users from 106
countries contributed to the online discussion, with non-professional individuals and health-
care organisations being the main influencers. Content was dominated by the words ‘kidney’,
‘stones’,‘pain’,‘urine’and ‘risk’, and tweets had more positive than negative sentiments. The
top links, photos and retweets were shared up to 100 times.
The Twitter activity of 10,806 tweets found for #KidneyStones in the study period is much
higher than 880 tweets found in 2012 for urinary tract infection, another urological disease
[14]. The majority of Twitter activity data in the literature are published on urological oncology
diseases, such as #testicularcancer (10,376 tweets in 2014) or #prostatecancer (79,242 tweets in
2014) [15]. Comparisons of tweet activity between #KidneyStones as a benign disease and
malignant diseases are compromised since the potentially life-threatening character of onco-
logical topics has been shown to provoke an over-representation on Twitter [14].
The tweet metric analysis showed that contributors interacted using retweets (24%) and
mentions (30%) in their tweets. Relevant tweets inducing retweets are of high interest to the
Fig 3. Geolocation of users contributing to the #KidneyStones online discussion on Twitter. The colour tone reflects the number of users
per country: the colour shifts from light tones (countries with few or no users) to dark tones (countries with many users).
doi:10.1371/journal.pone.0160863.g003
Online Discussion on #KidneyStones
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Twitter community, which is underlined by the recently introduced concept of the Twitter
impact factor [16]. Moreover, almost half of the tweets were enhanced by a link. This is encour-
aging since the combination ‘statement + proof’is a basic principle in science which can be
translated to Twitter as the combination ‘statement + link’. A tweet analysis on the topic of
dementia showed that the top users applied links more frequently than average users [17]. Sim-
ilarly, successful tweets from public state health departments contained links in the majority of
tweets [18]. Thus, a high number of links used in tweets for #KidneyStones appears to enhance
the reach of tweets and enables followers to check the trustworthiness of the short information
presented in one tweet. Additionally, links enable more information to be conveyed in the
tweet than the 140 characters would otherwise allow.
The Twitter discussion on #KidneyStones is global, involving users from all continents.
Usage rates of social media were 74% among American urologists in 2013 [19] and 70% among
Australian urologists in 2014 [1]. As social media adoption rates continue to grow, so did the
number of cumulative contributors to the #KidneyStones discussion. This is in line with our
previous study on urologic oncology, with steadily increasing tweet activity over time [15].
Twitter allows for rapid, informal, and thus low-threshold, participation in an online discus-
sion. These characteristics make it appealing for laypeople to join in the conversation. Notably,
Fig 4. Top 100 influencers in the #KidneyStones online discussion on Twitter according to tweet volume stratified by healthcare category.
Healthcare organisation consists of 8% provider, 1% government, 15% advocate/support and 13% other healthcare organisations (from darker blue to lighter
blue). Healthcare individual consists of 13% doctors, 2% healthcare practitioners and 4% other healthcare individuals (from darker turquoise to lighter
turquoise).
doi:10.1371/journal.pone.0160863.g004
Online Discussion on #KidneyStones
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individuals such as patients, relatives and interested people who are not primarily involved in
healthcare accounted for a large number of the top influencers in the #KidneyStones discus-
sion. Similarly, individual and organisational healthcare professionals contributed as top influ-
encers, which demonstrates the potential of Twitter for disseminating valuable knowledge
from professionals on preventive, diagnostic and therapeutic options to the populace.
Particularly noteworthy is the finding of the content analysis, revealing that words symbolis-
ing disease awareness and prevention are most frequently used in tweets on #KidneyStones.
Primary prevention of kidney stones has been shown to be cost-effective for a national health-
care system [20]. This is crucial, particularly considering the rapidly increasing costs of urolith-
iasis treatment, predicted to be more than US$1 billion annually in the United States by 2030
Fig 5. Bubble chart visualising the 100 most frequently used words in tweets in the #KidneyStones online discussion on Twitter. The larger the
bubble, the more a word is used. Colours only aid differentiation and have no other significance.
doi:10.1371/journal.pone.0160863.g005
Online Discussion on #KidneyStones
PLOS ONE | DOI:10.1371/journal.pone.0160863 August 18, 2016 8/11

[9]. Importantly, urolithiasis is associated with a 30–50% risk of recurrence within seven years
of initial treatment [21,22]. Secondary nonmedical prevention with fluid intake, specific die-
tary therapy, adoption of a ‘healthy’lifestyle [23–25] as well as preventive pharmacological
treatment [26–28] were reported to effectively reduce recurrence rates. Unfortunately, due to
patient and provider scepticism about the evidence of secondary prevention effectiveness, it is
infrequently utilised in daily routines [29,30]. An additional hurdle to the implementation of
preventive measures is low patient compliance; roughly half of stone formers were reported to
adhere to a prescribed preventive therapy in a contemporary series [30]. Considering the
under-utilised potential of primary and secondary prevention of urolithiasis, the Twitter plat-
form might make a beneficial contribution in these areas. The #KidneyStones Twitter discus-
sion can deliver currently valid guidelines and recommendations on urolithiasis prevention to
laypeople and thus lead to both a decrease of recurrence rates and increased cost-savings. In
this context, using links and photos to enhance a tweet’s content and its reach can therefore be
a successful strategy. The most shared link in our analysis was distributed 587 times and the
most shared photos and retweets were spread up to nearly 100 times.
Although the #KidneyStones hashtag is proposed as standardised communication descrip-
tor [5], we acknowledge that this single hashtag cannot capture all the information that is
exchanged on urolithiasis on the Twitter platform. Particularly during congresses with high
tweet activity using multiple hashtags, discussions on stone disease might take place beside the
#KidneyStones channel.
We also used the Symplur Signals analytics platform for a systematic assessment of health-
care social media data. The automated data extraction and analysis algorithms allow for the
analysis of a vast amount of data, but cannot detect linguistic nuances, such as ambiguity or
irony when analysing content. Lastly, Twitter is a rapidly growing and changing social media
platform, implying that the results of our contemporary analysis might be out-dated in the
near future.
Notwithstanding the aforementioned limitations, several practice-oriented conclusions can
be drawn from the findings of the current study. The Twitter discussion on #KidneyStones is
maintained by users from all over the world and evokes a remarkable number of tweets, under-
scoring the global reach of this microblogging platform. Healthcare organisations, as one of the
top influencers in the discussion, have a unique opportunity to raise the awareness of patients
and providers for nonmedical and pharmacological prevention, eventually reducing recurrence
rates and care-related expenditure. Patients and other laypeople substantially contributing to
the discussion have the option of being discreetly and noncommittally counselled by experts,
optimising shared decision-making. Finally, given responsible Twitter usage, the dissemination
of novel diagnostic and therapeutic developments in the area of urolithiasis between stakehold-
ers and patients might be considerably accelerated.
Conclusion
The Twitter discussion on #KidneyStones engaged multiple stakeholders in the healthcare sec-
tor on a global scale and involves both professionals and laypeople. Considering the rapidly
increasing prevalence and treatment-related costs of urolithiasis, Twitter might promote
shared decision-making and contribute to the optimisation of patient care.
Supporting Information
S1 Table. Geolocation of users of the #KidneyStones online discussion on Twitter.
(XLSX)
Online Discussion on #KidneyStones
PLOS ONE | DOI:10.1371/journal.pone.0160863 August 18, 2016 9/11

S2 Table. Top 100 words used in the #KidneyStones online discussion on Twitter.
(XLSX)
Acknowledgments
The authors wish to thank all the participants in the lively Twitter discussion on
#KidneyStones.
Author Contributions
Conceived and designed the experiments: JS HB IT.
Performed the experiments: JS HB IT.
Analyzed the data: JS HB MB HMF A. Haferkamp A. Heidenreich AM AN TK CT IT.
Contributed reagents/materials/analysis tools: JS HB IT.
Wrote the paper: JS HB MB HMF A. Haferkamp A. Heidenreich AM AN TK CT IT.
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Online Discussion on #KidneyStones
PLOS ONE | DOI:10.1371/journal.pone.0160863 August 18, 2016 11 / 11