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Facebook advertising for participant recruitment into a blood pressure clinical trial

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Objectives: Recruitment of sufficient sample size into clinical trials is challenging. Conventional advertising methods are expensive and are often ineffective. The effectiveness of Facebook for recruitment into blood pressure clinical trials of middle-to-older-aged people is unknown. This study aimed to assess this by comparing Facebook advertising with conventional recruitment methods from a retrospective analysis within a clinical trial. Methods: Conventional advertisements (newspaper, radio and posters) were employed for the first 20 months of a randomized controlled clinical trial conducted in three Australian capital cities from Tasmania, Queensland and the Australian Capital Territory. With dwindling participant recruitment, at 20 months a Facebook advertising campaign was employed intermittently over a 4-month period. Recruitment results were retrospectively compared with those using conventional methods in the previous 4 months. Results: Compared with conventional recruitment methods, Facebook advertisement was associated with a significant increase in the number of participants recruited in the Australian Capital Territory (from an average 1.8-7.3/month; P < 0.05). There was also an increase in Tasmania that was of borderline significance (from 4.0 participants recruited/month to 9.3/month; P = 0.052). However, there was no effect in Queensland (from 6.0 participants recruited/month to 3.0/month; P = 0.15). Facebook advertisement was associated with a significant decrease in the age of participants enquiring into the study (from 60.9 to 58.7 years; P < 0.001). Conclusion: Facebook advertising was successful in helping to increase recruitment of middle-to-older aged participants into a blood pressure clinical trial, although there may be some variability in effect that is dependent on location.
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JH-D-17-00388
Facebook advertising for participant recruitment into
a blood pressure clinical trial
Erin L. Nash
a
, Deborah Gilroy
b
, Wichat Srikusalanukul
c
, Walter P. Abhayaratna
c
, Tony Stanton
d,e
,
Geoffrey Mitchell
e,f
, Michael Stowasser
b
, and James E. Sharman
a
Objectives: Recruitmentofsufficientsamplesizeinto
clinical trials is challenging. Conventional advertising
methods are expensive and are often ineffective. The
effectiveness of Facebook for recruitment into blood
pressure clinical trials of middle-to-older-aged people is
unknown. This study aimed to assess this by comparing
Facebook advertising with conventional recruitment
methods from a retrospective analysis within a clinical
trial.
Methods: Conventional advertisements (newspaper, radio
and posters) were employed for the first 20 months of a
randomized controlled clinical trial conducted in three
Australian capital cities from Tasmania, Queensland and
the Australian Capital Territory. With dwindling participant
recruitment, at 20 months a Facebook advertising
campaign was employed intermittently over a 4-month
period. Recruitment results were retrospectively compared
with those using conventional methods in the previous 4
months.
Results: Compared with conventional recruitment
methods, Facebook advertisement was associated
with a significant increase in the number of
participants recruited in the Australian Capital Territory
(from an average 1.87.3/month; P<0.05). There was
also an increase in Tasmania that was of borderline
significance (from 4.0 participants recruited/month to
9.3/month; P¼0.052). However, there was no effect in
Queensland (from 6.0 participants recruited/month to
3.0/month; P¼0.15). Facebook advertisement was
associated with a significant decrease in the age of
participants enquiring into the study (from 60.9 to
58.7 years; P<0.001).
Conclusion: Facebook advertising was successful in
helping to increase recruitment of middle-to-older aged
participants into a blood pressure clinical trial, although
there may be some variability in effect that is dependent
on location.
Keywords: direct-to-consumer advertising, direct-to-
consumer marketing, research subject selection, social
mediums, web 2.0
Abbreviations: ACT, Australian Capital Territory; QLD,
Queensland; TAS, Tasmania
INTRODUCTION
For the appropriate conduct of clinical trials, inves-
tigators must demonstrate that the size and profile of
the study population is adequate to answer the study
question [1] and the potential to recruit the required number
of participants within the recruitment period [2]. Even with
the apparent availability of eligible study participants, the
recruitment of sufficient study sample in a timely manner
often presents a major challenge. Indeed, less than 10% of
clinical studies are completed on time due to poor partici-
pant recruitment and retention [3]. The use of conventional
recruitment methods, in particular press advertisements
and mail outs, can be expensive with no guarantee of
sufficient recruitment. With increasing popularity of online
media [4], web-based social platforms present a potential
opportunity for participant recruitment.
Facebook (Menlo Park, California, USA) is a form of
online social media, in which users are able to interact with
other users by sharing personal information into a news-
feed. As of January 2017, there were more than 1.86 billion
active monthly users of Facebook worldwide, representing
an annual increase of 17% [5]. In 2016, Facebook was the
most frequented website in Australia with users spending
approximately 12.5 h/week visiting the site [6]. Facebook
has been used successfully for recruitment of young par-
ticipants in online surveys [7], longitudinal studies [8,9] and
randomized controlled trials [10], but to our knowledge,
there are no reports on the value of Facebook for recruit-
ment in cardiovascular-related trials of older people. In this
article, we report the results of a retrospective analysis in
which Facebook advertising was included after conven-
tional recruitment methods had become exhausted in a
Journal of Hypertension 2017, 35:000–000
a
Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania,
b
Endocrine Hypertension Research Centre, University of Queensland School of Medi-
cine, Princess Alexandra Hospital, Brisbane, Queensland,
c
Australia National Universi-
ty, Canberra Hospital, Canberra, Australian Capital Territory,
d
Sunshine Coast
University Hospital, Birtinya,
e
School of Medicine, University of Queensland, Brisbane
and
f
Limestone Medical Centre, Ipswich, Queensland, Australia
Correspondence to James E. Sharman, PhD, Menzies Institute for Medical Research,
University of Tasmania, Private Bag 23, Hobart 7000, TAS, Australia. Tel: +61 3 6226
4709; fax: +61 3 6226 7704; e-mail: James.Sharman@utas.edu.au
Received 3 April 2017 Revised 5 June 2017 Accepted 21 June 2017
J Hypertens 35:000–000 Copyright ß2017 Wolters Kluwer Health, Inc. All rights
reserved.
DOI:10.1097/HJH.0000000000001477
Journal of Hypertension www.jhypertension.com 1
Original Article
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JH-D-17-00388
randomized controlled trial among middle-to-older aged
people treated for high blood pressure (BP).
METHODS
Study participants
The randomized controlled trial was entitled Tar-
geted LOWering of Central Blood Pressure Trial
(ACTRN12613000053729) and required recruitment of
300 participants from three study sites located in Australian
capital cities within Tasmania (TAS), the Australian Capital
Territory (ACT) and Queensland (QLD). Inclusion criteria
included men and women with high BP aged 1869 years
that were currently taking medication for high BP. Exclu-
sion criteria included if participants were taking more than
three BP medications, had a clinical history of cardiovascu-
lar disease, or were taking medications or supplements that
were contraindicated with the study medication.
Study protocol
The study was approved by local Human Research Ethics
Committees and participants provided informed consent.
At the start of the study, participant recruitment was under-
taken through conventional methods of advertising that
included posters in hospitals and doctors’ clinics, local
newspaper advertisements and inclusion of study informa-
tion slips within antihypertensive prescriptions distributed
at pharmacies. Study information was also made available
via a webpage linked to the TAS study site. In addition,
there were calls for study participants made via several
sources, including radio interviews, local publicly available
seminars and community events. Conventional recruitment
campaigns ran for the first 20 months of the trial, by which
time it became clear that recruitment options were becom-
ing exhausted as the number of enquiries had diminished
significantly. At this point, the Facebook campaign was
initiated at all study sites as an add-on measure to try and
increase recruitment. However, an additional source of
recruitment was also made available at the QLD site in
the months preceding the Facebook campaign, involving
identifying potential participants at a regional general prac-
tise located in Ipswich, 40 km from Brisbane city. The
practise database of approximately 5000 patients was
screened for potentially eligible participants and letters
were sent via the attending general practitioners with a
request to contact the practise, if interested in study partici-
pation.
Facebook advertisements
Intermittent broadcast of Facebook advertisements were
initiated over a 4-month period. Two forms of advertise-
ment were used first, those placed in the right-side panel
of the Facebook newsfeed and; second, those placed
directly into the newsfeed through the University of TAS
Facebook page. Right-side panel advertisements included
an image (up to five images could be used), a 20-character
title and 95-character text body. The newsfeed advertise-
ments allowed more text to be included in the title and body
sections (refer to Fig. 1 for examples). If people clicked
onto either form of advertisement, they were redirected to
the study website, which contained additional study infor-
mation and site coordinator contact details. Advertisements
were broadcast to a radius of 50 miles (80 km) around the
study sites in TAS and ACT, and a 30-mile radius (48 km)
around the QLD study sites (one each in Brisbane and
Ipswich; lower radius used due to much higher population
in QLD). Advertisements were able to be targeted towards
men and women aged between 35 and 69 years as these
details were included as part of registering for Facebook.
The daily cost for advertisements was capped at Australian
dollars (AUD$)25/day for newsfeed advertisements and
AUD$50/day for right-side panel advertisements in TAS
and ACT, and AUD$30/day for newsfeed advertisements
and AUD$100/day for right-side panel advertisements in
QLD. Once the daily cost had been reached, advertisements
would cease appearing for that day. Cost was calculated per
click onto advertisement which varied from AUD$0.20 to
AUD$1.20/click.
Statistical analysis
Success of Facebook advertising was gauged by a change in
the number of new enquiries and number of new partic-
ipants recruited at each site in the 4-month period using
Facebook advertising compared with the 4 months preced-
ing Facebook advertising. With respect to age of partici-
pants, we compared the values for the 20-month
conventional recruitment period with the values for the
Facebook recruiting period. Differences between groups
were assessed using Student’s two-tailed ttests for contin-
uous variables and independent two-tailed ttest was used
on age related data. Data has been presented as mean
standard deviation unless otherwise specified and statistical
significance was denoted by Pvalue less than 0.05.
RESULTS
Table 1 presents Facebook statistics related to the 4-month
advertising period. Figures 2 and 3 present site-specific
comparisons on the number of enquiries and participants
recruited related to Facebook advertising. In ACT, this was
associated with a significant increase in the average number
of enquiries to participate in the study (from 6.5 to 22.0
enquiries/month; P<0.05) and average number of particip-
ants recruited (from 1.8 to 7.3 participants recruited/month;
P<0.05) when compared with the previous 4-month peri-
od only using conventional advertising methods. In TAS,
there was a significant increase in the average number of
enquiries to participate in the study (from 12.5 to 28.5
enquiries/month; P<0.05) and a trend towards an increase
in average number of participants (from 4.0 to 9.3 partic-
ipants recruited/month; P¼0.052). However, in QLD, there
was a nonsignificant decrease in the average number of
enquiries from pre to post Facebook advertising (from 22.8
to 11.0 enquiries/month; P¼0.23; Fig. 2). Similarly, for
QLD, there was a nonsignificant reduction in the number
of participants recruited from pre to post Facebook adver-
tising (from 6 to 3/month; P¼0.23; Fig. 3). The reversal in
trends at the QLD site appears to be related to the higher
average numbers of enquiries (Fig. 2) and participants
recruited (Fig. 3) in the 4 months preceding initiation of
Facebook. This period also coincided with the additional
Nash et al.
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source of recruitment at the regional general practise
in QLD. The average monthly ratio of the number of
people recruited per enquiries made to study staff was
not significantly different from preinitiation to postinitia-
tion of Facebook at any site (ACT 0.20 vs. 0.31; P¼0.09,
TAS 0.36 vs. 0.26; P¼0.13, QLD 0.44 vs. 0.37; P¼0.38).
Compared with the first 20 months using conventional
recruitment methods, the average age of participants
contacting coordinators at all sites was significantly re-
duced after Facebook advertising (from 60.9 9.4 to
58.7 8.8 years; P<0.001).
DISCUSSION
To our knowledge, this study is the first to report on the
effect of Facebook advertising to engage and enhance
participant recruitment in a BP randomized controlled trial
of middle-to-older aged people. This was a retrospective
analysis from within an existing trial. The main findings
were that Facebook advertising was successful at increasing
the number of enquiries and participants recruited at two of
three national clinical trial study sites. It is also of note that
Facebook was successful in recruiting a cohort of particip-
ants in an older age bracket typical of cardiovascular-
0
5
10
15
20
25
30
35
40
TAS ACT QLD
Average number of enquiries /month
Convenonal adversements Convenonal + Facebook adversements
*
*
p= 0.16
FIGURE 2 Comparison of the average (SEM) number of enquiries from potential
study participants in the 4-month period pre (black bars) and post (open bars)
Facebook advertising in Tasmania, Australian Capital Territory and Queensland
study sites.
P<0.05.
TABLE 1. Statistics from the 4-month period where Facebook
advertisements were available intermittently at
clinical trial sites in Tasmania, Australian Capital
Territory and Queensland
Variable TAS ACT QLD
Days advertisements run, n80 55 49
Potential viewers, n49 912 23 781 154 477
Clicks onto advertisement, n3436 2521 1970
Enquiries to study staff, n114 88 44
Randomized participants, n30 26 11
Average cost per click (AUD) 0.80 0.43 0.98
Total cost of all advertisements (AUD) 2527 1174 1936
Average cost/enquiry to study staff (AUD) 22.17 13.34 44.00
Average cost/participant randomized (AUD) 84.23 45.15 176.00
ACT, Australian Capital Territory; AUD, Australian dollars; QLD, Queensland; TAS,
Tasmania.
FIGURE 1 Examples of Facebook advertisements placed on right-side panel to the Facebook newsfeed (a) and advertisement placed directly into newsfeed from the
University of Tasmania Facebook page (b).
Facebook and trial recruitment
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related trials, although the average age was lower than
participants recruited prior to Facebook advertising. These
observations suggest that Facebook may be a useful tool to
enhance clinical trial recruitment.
Initiation of Facebook advertising was associated with
improved recruitment at two study sites (TAS and ACT), but
not in QLD, where there was a nonstatistically significant
trend for a reduction in the number of enquiries to study
staff as well as the number of participants recruited.
Although we cannot definitively identify the reasons for
this discrepancy, there are two factors that are likely to have
been contributory. First, a new source of recruitment was
opened at the QLD site in the months prior to Facebook
initiation, and this resulted in a boost in both enquiries and
number of participants recruited. Thus, the baseline level
for these metrics was higher at QLD compared with the
other study sites (Figs. 2 and 3). Second, the QLD site was a
larger metropolitan centre with a greater population than
the other study sites, and location differences could have
played a role. Indeed, recruitment rates vary significantly
between regions and medical practises, with lower rates
reported in a large capital city (London) compared with a
smaller city (Edinburgh) [11]. A key barrier for participation
in large cities is greater burden from long journey times [12],
and our study design involved many visits for participants.
Thus, despite QLD having a much larger population com-
pared with the other sites, it may be that Facebook adver-
tising cannot overcome difficulties of recruiting participants
in large capital cities.
The average age of study participants recruited after
initiation of Facebook advertising was statistically younger
(albeit only 2 years lower on average) than participants
recruited via conventional advertising. Although this
result was among a population of middle-to-older aged
participants, similar observations have been reported in
the recruitment of younger people into a clinical trial of
smoking cessation, whereby online-recruited participants
were aged 38.8 12.1 years compared with 45.6 13.5
years for traditional advertising. However, there were no
other differences in terms of socio-economic variables [13].
According to 2016 statistics, irrespective of age, Facebook
was the most popular social networking site, and older
people generally had the same reasons as young people for
using social networking (e.g. catching up with family and
friends, sharing photographs, getting information on news
and current events) [5]. Significantly, over the previous year
from 2016, the time spent on social networking had in-
creased to about the same level among people aged
65 years or older (23%) compared with those aged 18
29 (22%), 3039 (27%) and 4049 years (26%) [6]. Social
media platforms are increasingly used for medical market-
ingtoprovideinformationtoendusersonhealthand
disease, with pharmaceutical companies, hospitals, medi-
cal research institutes and professional societies (e.g. dia-
betes education) participating in this arena [5]. Altogether
these data appear to indicate an increase in the opportu-
nities available to recruit older participants (in good
health or with existing disease) into clinical studies
using Facebook.
Limitations
The study presents findings from a retrospective observa-
tional analysis within a randomized controlled trial rather
than being specifically designed to determine the effects of
Facebook advertising on recruitment for a BP-related trial.
Thus, we cannot make definitive conclusions on the effects
of Facebook advertising, and more rigorous studies are
needed to determine if the concept is more generalizable. A
complete cost breakdown for the conventional recruitment
approach was not available due to the retrospective nature
of the study, and as such we cannot compare the cost
differences with Facebook advertising. This would also
need to be determined in future studies.
In conclusion, the current study found that using Face-
book advertising was effective for increasing recruitment of
older aged participants into a national BP-related study.
Effectiveness of recruitment using Facebook appeared to
be location dependent, with greater success among the
smaller, regional centres. Overall, Facebook seems to
reach a proportion of the population potentially interested
in clinical trial participation that is above and beyond
the attainable using conventional advertising methods
alone.
ACKNOWLEDGEMENTS
We are very grateful to Raylene Steinhardt (Practice Man-
ager, Limestone Medical Centre) for help in recruiting
participants for this study.
J.E.S. was supported by a National Health and Medical
Research Council (NHMRC) Career Development Award
(reference 569519) and the study was supported by an
NHMRC Project Grant (reference 1044551).
Conflicts of interest
There are no conflicts of interest.
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Average number of parcipants recruited/month
Convenonal adversements Convenonal + Facebook adversements
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Nash et al.
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Reviewer’s Summary Evaluation
Reviewer 1
Participant recruitment is often the primary reason
for slower than optimal progress in the conduct of
clinical trials. This study suggests that Facebook adver-
tising could be a useful approach to recruiting parti-
cipants. More efficient recruitment would save time
and money.
Facebook and trial recruitment
Journal of Hypertension www.jhypertension.com 5
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... 3,[5][6][7] At present, little evidence is available on the efficacy of using social media to recruit patients into cardiovascular and hypertension trials. 8 The aim of the present study was to evaluate the efficacy of social ...
... The use of targeted social media through Facebook was an efficient strategy to find candidates for a prospective randomized hypertension trial. Our findings add to previous studies assessing the efficacy of Facebook campaigns to recruit participants into an observational blood pressure trial by Nash et al. 8 in Australia and Tasmania, in which the authors concluded that Facebook ads were associated with a significant increase in the recruited number of patients/month. In the latter study, an increase in the recruited number was found to be strongly location dependent with a higher yield in densely populated regions. ...
... A finding that can be explained by the higher overall age of Facebook users. The latter was also in line with the study of Nash et al., 8 in which Facebook was successful in recruiting a cohort of patients at higher age. According to the data of the Pew Research Center in 2018, more older people use Facebook and Youtube, whereas younger people use more Instagram. ...
Article
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Aims The present study aimed to evaluate the potential of social media as an approach to recruit hypertensive subjects. Methods and results In addition to conventional trial recruitment, Facebook ads were run. Over a 115-day recruitment period, Facebook reached 5.3 million people in 168 separate campaigns run in the proximity of 19 sites in the USA and 14 sites in Europe. A total of 182 839 participants (3.4%) clicked on the ad; of those 10 483 subjects (5.7%) completed a dedicated questionnaire. This resulted in 3632 potential candidates. A total of 285 potential candidates were recruited by various recruitment strategies in the specified time period, of which 184/285 (64.6%) came from Facebook. When comparing Facebook with a 7-day radio spot in the same time period, 48 radio spots were launched; resulting in nine inquiries with eventually five potential candidates and two consents. Conclusion Targeted social media was a successful and efficient strategy to recruit hypertensive subjects.
... Langbaum et al. 10 were able to enrol 75,351 cognitively healthy adults aged 55-75 years in USA into a registry (GeneMatch) of Alzheimer's disease prevention studies online, over half of whom (60%) joined the registry based on social media ads. A second study by Nash et al. 11 reported dwindling participant ...
... Sample representativeness Some study teams have reported sample representativeness issues such as the decrease in the age of participants as a result of social media-based recruitment. 11 However, studies have also demonstrated the utility of social media to recruit diverse participants with respect to race and ethnicity, education, and employment. 13 Recruiting across multiple social media platforms is recommended to optimise sample diversity. ...
... Over half of those participants (45,210/75,351, 60%) joined GeneMatch via SM advertisements (ads). Another study reported dwindling participant recruitment and later showed a significant increase in the recruitment of middle-to-older-aged people into a blood pressure randomized controlled trial after implementing a Facebook advertising campaign [27]. Lam and Woo [28] demonstrated the cost-effectiveness of Facebook to recruit elder Chinese-speaking Americans into a health education study. ...
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Background: Participant recruitment remains a barrier to conducting clinical research. The disabling nature of a stroke, which often includes functional and cognitive impairments, and the acute stage of illness at which patients are appropriate for many trials make recruiting patients particularly complex and challenging. In addition, people aged 65 years and older, which includes most stroke survivors, have been identified as a group that is difficult to reach and is commonly underrepresented in health research, particularly clinical trials. Digital media may provide effective tools to support enrollment efforts of stroke survivors in clinical trials. Objective: The objective of this study was to compare the effectiveness of general practice (traditional) and digital (online) methods of recruiting stroke survivors to a clinical mobility study. Methods: Recruitment for a clinical mobility study began in July 2018. Eligible study participants included individuals 18 years and older who had a single stroke and were currently ambulatory in the community. General recruiting practice included calling individuals listed in a stroke registry, contacting local physical therapists, and placing study flyers throughout a university campus. Between May 21, 2019, and June 26, 2019, the study was also promoted digitally using the social network Facebook and the search engine marketing tool Google AdWords. The recruitment advertisements (ads) included a link to the study page to which users who clicked were referred. Primary outcomes of interest for both general practice and digital methods included recruitment speed (enrollment rate) and sample characteristics. The data were analyzed using the Lilliefors test, the Welch two-sample t test, and the Mann-Whitney test. Significance was set at P=.05. All statistical analyses were performed in MATLAB 2019b. Results: Our results indicate that digital recruitment methods can address recruitment challenges regarding stroke survivors. Digital recruitment methods allowed us to enroll study participants at a faster rate (1.8 participants/week) compared to using general practice methods (0.57 participants/week). Our findings also demonstrate that digital and general recruitment practices can achieve an equivalent level of sample representativeness. The characteristics of the enrolled stroke survivors did not differ significantly by age (P=.95) or clinical scores (P=.22; P=.82). Comparing the cost-effectiveness of Facebook and Google, we found that the use of Facebook resulted in a lower cost per click and cost per enrollee per ad. Conclusions: Digital recruitment can be used to expedite participant recruitment of stroke survivors compared to more traditional recruitment practices, while also achieving equivalent sample representativeness. Both general practice and digital recruitment methods will be important to the successful recruitment of stroke survivors. Future studies could focus on testing the effectiveness of additional general practice and digital media approaches and include robust cost-effectiveness analyses. Examining the effectiveness of different messaging and visual approaches tailored to culturally diverse and underrepresented target subgroups could provide further data to move toward evidence-based recruitment strategies.
... One study used untargeted Facebook ads, then switched to targeted Facebook ads that showed ads only to participants who met the study criteria [22]. Several studies started using social media after other recruitment methods were deployed [28,31,38,44], while others used social media at the beginning of their recruitment period. ...
Article
Background Recruiting participants into clinical trials continues to be a challenge, which can result in study delay or termination. Recent studies have used social media to enhance recruitment outcomes. An assessment of the literature on the use of social media for this purpose is required. Objective This study aims to answer the following questions: (1) How is the use of social media, in combination with traditional approaches to enhance clinical trial recruitment and enrollment, represented in the literature? and (2) Do the data on recruitment and enrollment outcomes presented in the literature allow for comparison across studies? Methods We conducted a comprehensive literature search across 7 platforms to identify clinical trials that combined social media and traditional methods to recruit patients. Study and participant characteristics, recruitment methods, and recruitment outcomes were evaluated and compared. Results We identified 2371 titles and abstracts through our systematic search. Of these, we assessed 95 full papers and determined that 33 studies met the inclusion criteria. A total of 17 studies reported enrollment outcomes, of which 9 achieved or exceeded their enrollment target. The proportion of participants enrolled from social media in these studies ranged from 0% to 49%. Across all 33 studies, the proportion of participants recruited and enrolled from social media varied greatly. A total of 9 studies reported higher enrollment rates from social media than any other methods, and 4 studies reported the lowest cost per enrolled participant from social media. Conclusions While the assessment of the use of social media to improve clinical trial participation is hindered by reporting inconsistencies, preliminary data suggest that social media can increase participation and reduce per-participant cost. The adoption of consistent standards for reporting recruitment and enrollment outcomes is required to advance our understanding and use of social media to support clinical trial success.
... Facebook, as a social media platform, was also found to have a good auxiliary function for clinical treatment of cardiovascular disease [17,18]. Social media were widely used in chronic diseases and clinical research, but there are few studies on self-management of patients with hypertension [19,20]. Secondly, the social media platforms which are currently being applied and studied are mainly based on popular software (such as Facebook, Tweets, SMS, etc.) in western countries. ...
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Background: Digital health tools (WeChat or mobile health apps) provide opportunities for new methods of hypertension management for hypertensive patients. However, the willingness of these patients to use social media and mobile health apps for hypertension management remains unclear. This study explored the characteristics and requirements of patients willing to use digital health (WDH) tools to manage hypertension. Methods: From February to March 2018, we administered questionnaires to 1089 patients with hypertension at eight Chinese primary medical units. We assessed independent risk factors of WDH and requirement among WDH patients. Results: Overall, 43% (465/1089) of participants were WDH patients, who were younger (58 ± 12 vs 61 ± 13 years) and had a greater proportion of employed individuals (31% vs 14%) and higher education levels (65% vs 52%) than the non-WDH patients (all P < 0.0001). After adjusting for other risk factors, higher education (OR: 0.52; 95% CI: 0.34-0.79), good medicine adherence (OR: 1.5; 95% CI: 1.0-2.3) and blood pressure self-monitoring (OR: 1.6; 95% CI: 1.2-2.3) remained significantly associated with WDH (all P < 0.05). WDH patients responded that digital health tools should try to provide a platform for blood pressure monitoring (42%), medication reminders (41%), hypertension knowledge (39%) and doctor-patient communication (32%). Conclusion: Our survey suggested that among hypertensive patients, willingness to use digital health tools was significantly associated with education, medicine adherence and blood pressure self-monitoring. Digital health tool developers and researchers should pay particular attention to recruiting older, less educated and unemployed patients with less willingness and who are less technologically savvy and research the requirements of WDH patients (blood pressure monitoring, medication reminders, and knowledge education) in the future.
... The age of recruited participants differed between digital and non-digital recruitment methods in a number of the studies (e.g. [78,83,103,107,129,140,152]), indicating that the age of the target population should be taken into consideration when selecting recruitment tools. National statistics show that the proportion of adults who use the Internet (and also social media [170,171]) is lowest in the over-65 years' group [171][172][173], although the proportion of older people using the Internet has risen steadily in recent years [172,173], suggesting that some digital tools that may currently be out of reach of older people may become increasingly more accessible. ...
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Background: Recruiting and retaining participants in randomised controlled trials (RCTs) is challenging. Digital tools such as social media, data mining, e-mail or text messaging could improve recruitment or retention, but an overview of this research area is lacking. We aimed to systematically map the characteristics of digital recruitment and retention tools for RCTs, and the features of the comparative studies that have evaluated the effectiveness of these tools during the past 10 years. Methods: We searched Medline, Embase, other databases, the Internet, and relevant web sites in July 2018 to identify comparative studies of digital tools for recruiting and/or retaining participants in health RCTs. Two reviewers independently screened references against protocol-specified eligibility criteria. Included studies were coded by one reviewer with 20% checked by a second reviewer, using pre-defined keywords to describe characteristics of the studies, populations and digital tools evaluated. Results: We identified 9163 potentially relevant references, of which 104 articles reporting 105 comparative studies were included in the systematic map. The number of published studies on digital tools has doubled in the past decade, but most studies evaluated digital tools for recruitment rather than retention. Key health areas investigated were health promotion, cancers, circulatory system diseases, and mental health. Few studies focused on minority or under-served populations, and most studies were observational. The most frequently-studied digital tools were social media, internet sites, email and tv/radio for recruitment; and email and text messaging for retention. One quarter of the studies measured efficiency (cost per recruited or retained participant) but few studies have evaluated people’s attitudes towards the use of digital tools. Conclusions: This systematic map highlights a number of evidence gaps and may help stakeholders to identify and prioritise further research needs. In particular, there is a need for rigorous research on the efficiency of the digital tools and their impact on RCT participants and investigators, perhaps as studies-within-a-trial (SWAT) research. There is also a need for research into how digital tools may improve participant retention in RCTs which is currently underrepresented relative to recruitment research. Registration: Not registered; based on a pre-specified protocol, peer-reviewed by the project’s Advisory Board.<br/
... A recent study indicated that the response rate from older people to a social 429 media advertisement for recruiting participants into a clinical trial was higher than for 430 younger adults (Cowie and Gurney, 2018). Another recent study reported that the use of 431 social media was a successful strategy for recruiting older participants into a clinical trial 432 investigating cardiovascular outcomes (Nash et al., 2017). We also recruited participants 433 from a database of participants who had participated previously in other studies at Newcastle 434 University and who had expressed an interest to be involved in future research. ...
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Background Nitrate-rich food can increase NO production and may induce positive effects on brain function. This study examined the feasibility of a randomized clinical trial (RCT) testing the effects of prolonged consumption of incremental doses of dietary nitrate (NO3⁻) in overweight and obese older participants. Secondary aims tested dose-dependent changes in cognitive, vascular and pulmonary functions and cerebral blood flow (CBF). Methods This was a single blind, four-arm parallel RCT conducted in 60 overweight and obese older participants. Eligible participants were randomized to:1) high NO3⁻ (140 ml of beetroot juice (BJ) per day, ∼800 mg of NO3⁻/day), 2) moderate NO3⁻ (70 ml of BJ per day, ∼400 mg of NO3⁻/day), 3) low NO3⁻ (70 ml on alternate days, ∼400 mg of NO3⁻) or 4) NO3⁻ depleted (70 ml on alternate days, ∼0.001 mg of NO3). Measurements of cognitive, vascular and pulmonary functions and CBF were conducted at baseline and 13-weeks NO3⁻ intake was assessed by six 24-h recalls, and by measuring NO3⁻ intake biomarkers. Feasibility was assessed by obtaining qualitative feedback and evaluating trial recruitment, retention, compliance with study visits and measurement protocols. Results Participant recruitment started in July 2018 and ended in April 2019. Of all the recruitment strategies that were used, advertisement of the study via Facebook generated the highest response rate. Sixty-two participants consented and were enrolled. Overall, characteristics of included participants matched our recruitment criteria. Conclusion The findings from this study provide evidence of the acceptability and feasibility of an intervention investigating the effects of incremental doses of high-nitrate BJ over a prolonged period. Trial registration The intervention study was registered with clinical trial ISRCTN registry (ISRCTN14746723) on 27 December 2018.
Article
BACKGROUND: There is little peer-reviewed information about the strategic use of Facebook in companion animal veterinary settings, including for research recruitment. This study evaluates the implementation and execution of a Facebook strategy in a University Teaching and Research Hospital setting and the use of Facebook as a veterinary communication and recruitment tool. METHODS: All posts published on the hospital's Facebook page, messages sent via Messenger, and Facebook insight data from April 2017 to November 2019 (31 months) were reviewed and categorized. Facebook as a recruitment tool was evaluated through a survey among the faculty. RESULTS: A total of 113 posts were published, the Facebook page had 3485 followers and altogether 590,877 users were reached. The use of a Facebook strategy supported consistent management of the Facebook page. The content was well aligned with the strategy. The survey showed that the faculty experienced a facilitation effect by their recruitment posts, although the actual recruitment varied and ranged from none to the vast majority of all recruited subjects. CONCLUSIONS: This case-based, descriptive study gives insight and generates awareness about the possibilities and limitations of communication and research recruitment via Facebook. Further research is needed to evaluate if the findings can be generalized.
Article
Background: Web-based screening may be suitable for identifying individuals with presymptomatic latent diseases for recruitment to clinical studies, as such people do not often visit hospitals in the presymptomatic stage. The promotion of such online screening studies is critical to their success, although it remains uncertain how the effectiveness of such promotion can differ, depending on the different promotion methods, domains of interest, or countries of implementation. Objective: The Japanese Trial-Ready Cohort (J-TRC) web study is our ongoing online screening registry to identify individuals with presymptomatic Alzheimer disease (AD), aimed at facilitating the clinical trials for AD prevention. Within the first 9 months of its 2019 launch, the J-TRC web study recruited thousands of online participants via multiple methods of promotion, including press releases, newspaper advertisements, web advertisements, or direct email invitations. Here, we aimed to quantitatively evaluate efficacy and cost-effectiveness of each of these multimodal promotion methods. Methods: We applied the vector-autoregression model to assess the degree of contribution of each type of promotion to the following target metrics: number of daily visitors to the J-TRC website, number of daily registrants to the J-TRC web study, daily rate of registration among visitors, daily rate of eligible participants among registrants, and median age of daily registrants. The average cost-effectiveness for each promotion method was also calculated using the total cost and the coefficients in the vector-autoregression model. Results: During the first 9 months of the reviewed period from October 31, 2019 to June 17, 2020, there were 48,334 website visitors and 4429 registrations (9.16% of 48,334 visitors), of which 3081 (69.56%) were eligible registrations. Initial press release reports and newspaper advertisements had a marked effect on increasing the number of daily visitors and daily registrants. Web advertisements significantly contributed to the increase in daily visitors (P<.001) but not to the daily registrants, and it also lowered the rate of registrations and the median age of daily registrants. Website visitors from the direct email invitation sent to other cognitive registries seem to have registered with the highest reliability. The calculated average cost-effectiveness for the initial press release was US $24.60 per visitor and US $96.10 per registrant, while the calculated average cost-effectiveness for the newspaper advertisements was US $28.60 per visitor and US $227.90 per registrant. Conclusions: Our multivariate time-series analysis showed that each promotion method had different features in their effect of recruiting participants to the J-TRC web study. Under the advertisement condition settings thus far, newspaper advertisements and initial press releases were the most effective promotion methods, with fair cost-effectiveness that was equivalent to earlier online studies. These results can provide important suggestions for future promotions for the recruitment of presymptomatic participants to AD clinical trials in Japan.
Article
Patient recruitment and retention continue to present challenges in conducting clinical trials. The objectives of the study were to benchmark patient recruitment and retention practices across recent global clinical trials from a working group of biopharmaceutical companies and to re-visit the results from an earlier study published 7 years ago. The data collection focused on patient and site enrollment metrics and recruitment and retention tactics used for studies. Analyses were conducted comparing the results from 2012 and 2019. The results indicated that more studies met or exceeded planned enrollment than the previous research and global differences were observed in the present study for site activation rates and target to actual enrollment rates. Since an updated set of recruitment and retention tactics were evaluated in the present study, no comparisons were made to previous data. Researchers suggest further study that would examine usage and effectiveness of specific recruitment and retention tactics across global studies.
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Further understanding is needed of the functionalities and efficiency of social media for health intervention research recruitment. Facebook was examined as a mechanism to recruit young adults for a smoking cessation intervention. An ad campaign targeting young adult smokers tested specific messaging based on market theory and successful strategies used to recruit smokers in previous clinical trials (i.e. informative, call to action, scarcity, social norms), previously successful ads, and general messaging. Images were selected to target smokers (e.g., lit cigarette), appeal to the target age, vary demographically, and vary graphically (cartoon, photo, logo). Facebook's Ads Manager was used for over 7 weeks (6/10/13–7/29/13), targeted by age (18–25), location (U.S.), and language (English), and employed multiple ad types (newsfeed, standard, promoted posts, sponsored stories) and keywords. Ads linked to the online screening survey or study Facebook page. The 36 different ads generated 3,198,373 impressions, 5895 unique clicks, at an overall cost of $2024 ($0.34/click). Images of smoking and newsfeed ads had the greatest reach and clicks at the lowest cost. Of 5895 unique clicks, 586 (10%) were study eligible and 230 (39%) consented. Advertising costs averaged $8.80 per eligible, consented participant. The final study sample (n = 79) was largely Caucasian (77%) and male (69%), averaging 11 cigarettes/day (SD = 8.3) and 2.7 years smoking (SD = 0.7). Facebook is a useful, cost-effective recruitment source for young adult smokers. Ads posted via newsfeed posts were particularly successful, likely because they were viewable via mobile phone. Efforts to engage more ethnic minorities, young women, and smokers motivated to quit are needed.
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Recruiting the required number of participants is vital to the success of clinical research and yet many studies fail to achieve their expected recruitment rate. Increasing research participation is a key agenda within the NHS and elsewhere, but the optimal methods of improving recruitment to clinical research remain elusive. The aim of this study was to identify the factors that researchers perceive as influential in the recruitment of participants to clinically focused research. Semi-structured interviews were conducted with 11 individuals from three clinical research teams based in London. Sampling was a combination of convenience and purposive. The interviews were audio recorded, transcribed verbatim and analysed using the framework method to identify key themes. Four themes were identified as influential to recruitment: infrastructure, nature of the research, recruiter characteristics and participant characteristics. The main reason individuals participate in clinical research was believed to be altruism, while logistical issues were considered important for those who declined. Suggestions to improve recruitment included reducing participant burden, providing support for individuals who do not speak English, and forming collaborations with primary care to improve the identification of, and access to, potentially eligible participants. Recruiting the target number of research participants was perceived as difficult, especially for clinical trials. New and diverse strategies to ensure that all potentially eligible patients are invited to participate may be beneficial and require further exploration in different settings. Establishing integrated clinical and academic teams with shared responsibilities for recruitment may also facilitate this process. Language barriers and long journey times were considered negative influences to recruitment; although more prominent, these issues are not unique to London and are likely to be important influences in other locations.
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Studies of tobacco use and other health behaviors have reported great challenges in recruiting young adults. Social media is widely used by young adults in the United States and represents a potentially fast, affordable method of recruiting study participants for survey research. The present study examined Facebook as a mechanism to reach and survey young adults about tobacco and other substance use. Participants were cigarette users, age 18-25 years old, living throughout the United States and recruited through Facebook to complete a survey about tobacco and other substance use. Paid advertising using Facebook's Ad program over 13 months from 2010 Feb 28 to 2011 Apr 4 targeted by age (18-25), location (United States or California), language (English), and tobacco- and/or marijuana-related keywords. Facebook approved all ads. The campaign used 20 ads, which generated 28,683,151 impressions, yielding 14,808 clicks (0.7% of targeted Facebook members), at an overall cost of $6,628.24. The average cost per click on an ad was $0.45. The success of individual ads varied widely. There was a rise in both clicks and impressions as the campaign grew. However, the peak for clicks was 3 months before the peak for ad impressions. Of the 69,937,080 accounts for those age 18-25 in the United States, Facebook estimated that 2.8% (n = 1,980,240) were reached through tobacco and marijuana keywords. Our campaign yielded 5237 signed consents (35.4% of clicks), of which 3093 (59%) met criteria, and 1548 (50% of those who met criteria) completed the survey. The final cost per valid completed survey was $4.28. The majority of completed surveys came from whites (69%) and males (72%). The sample averaged 8.9 cigarettes per day (SD 7.5), 3.8 years of smoking (SD 2.9), with a median of 1 lifetime quit attempts; 48% did not intend to quit smoking in the next 6 months. Despite wide variety in the success of individual ads and potential concerns about sample representativeness, Facebook was a useful, cost-effective recruitment source for young-adult smokers to complete a survey about the use of tobacco and other substances. The current findings support Facebook as a viable recruitment option for assessment of health behavior in young adults.
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Recruiting smokers to smoking cessation trials is challenging and participation rates are often low. Consequently, the interventions evaluated may fail to reach a broad spectrum of the target population, thus compromising the generalizability of the findings. Brief interventions, using proactive recruitment, are likely to attract a broader and more representative proportion of the population. We explored the factors that influenced recruitment into a trial evaluating computer-tailored feedback reports that aimed to help smokers to quit [the ESCAPE (Effectiveness of computer-tailored Smoking Cessation Advice in Primary Care) study] in order to investigate the possibilities for increasing recruitment into smoking cessation trials. Current cigarette smokers, identified from GP records, were invited to participate in the study. The main outcome measure was the recruitment rate, i.e. the proportion of participants who responded and were randomized to one of the intervention groups. Predictor variables included geographical region, level of deprivation, practice characteristics and the number and timing of mailings of questionnaires. The recruitment rate varied by practice (2.5-19.8%) and differed significantly between regions (from 16.3% in Scotland to 8.4% in London, P < 0.001). Recruitment decreased significantly by 1.1% between the lowest and highest quintiles of deprivation (P = 0.012), measured by Index of Multiple Deprivation scores, and decreased by 1.33% for every extra 10% smokers identified within a practice population (P = 0.010). Sending reminders increased recruitment by 7.5% (P < 0.001). Multivariable analysis showed region and length of time between mailings were the main predictors of recruitment. Proactive recruitment methods can increase participation in smoking cessation trials and weighting the target sample in favour of more deprived areas will recruit a more representative sample. The number and timing of mailings to potential participants can also increase recruitment.
Article
College-age men were recruited using Facebook™ advertisements (ads), as well as traditional recruitment methods, for a randomized controlled trial to compare immunological responses to human papillomavirus vaccine administered in two dosing schedules. This study compares enrollees who were recruited through traditional recruitment methods versus social networking sites (SNSs), including Facebook. Potential participants were recruited using flyers posted on and off campus(es), and distributed at health fairs, classes, sporting, and other campus events; e-mails to students and student organizations; and print advertisements in student newspapers and on city buses. Facebook ads were displayed to users with specific age, geographic, and interest characteristics; ads were monitored daily to make adjustments to improve response. A total of 220 males, aged 18 to 25 years enrolled between October 2010 and May 2011. The majority of participants (51%) reported print advertisements as the method by which they first heard about the study, followed by personal contact (29%) and Facebook or other SNSs (20%). The likelihood of a SNS being the source by which the participant first heard about the study compared with traditional methods was increased if the participant reported (a) being homosexual or bisexual or (b) posting daily updates on SNSs. Facebook and other SNSs are a viable recruitment strategy for reaching potential clinical trial participants among groups who typically use social media to stay connected with their friends and hard-to-reach groups such as young men who self-identify as homosexual or bisexual.
Article
The aim of the present study was to explore the viability of using social media as a recruitment tool in a clinical research trial. Sociodemographic data and smoking characteristics were assessed in 266 participants recruited to investigate the effectiveness of a behavioral support program for smoking cessation. For analysis, participants were separated into two groups based on whether they were recruited either using traditional means (flyers, word of mouth, or newspaper advertisement; n = 125, 47.0%) or by advertisements in online social media (n = 138, 51.9%). Participants recruited via social media were significantly younger, but there were no differences in other socioeconomic variables or smoking characteristics compared with participants recruited via other traditional means. The findings of the present study suggest that using online social media is a viable recruitment method for smoking studies and compliments other more traditional recruitment methods.
Article
Recruitment and retention of adolescent research participants presents unique challenges and considerations when conducting epidemiological studies. To describe the use of the social networking website in the re-recruitment and tracking of adolescent girls into a follow-up study of the Trial of Activity for Adolescent Girls (TAAG) at the University of Maryland field site. 730 girls were recruited as 8th graders into TAAG. Re-recruitment efforts were conducted when they were 11th graders (TAAG 2). Traditional methods, including mailings and school visits, were conducted. A TAAG 2 Facebook site was created to search for girls not found through traditional recruitment methods. Chi-square and t-tests were conducted to identify differences in characteristics between those found and "friended" through Facebook and through traditional recruitment methods. There were 175 girls we were unable to locate using traditional recruitment methods. Of these, 78 were found on Facebook, 68 responded to our friend request, and 43 girls (6% of the girls previously recruited) participated in the study. Demographic data were similar for those who friended us on Facebook and traditional methods. 8th grade body mass index and percent body fat were lower for those recruited from Facebook (p=0.03 and 0.04, respectively). Number of daily minutes of moderate-to-vigorous physical activity tended to be lower among the TAAG 2 Facebook friends (19 ± 11 vs 21 ± 11, p=0.06). Loss to follow-up was minimized by contacting potential participants through Facebook. Social networking websites are a promising method to recruit adolescents.
Canberra, ACT: National Health and Medical Research Council, the Australian Research Council and the Australian Vice-Chancellors' Committee
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