Remote clinical trials with inclusive social media recruitment may help improve racial, ethnic, and geographic diversity among clinical trial participants, according to a US study published early this week in JAMA Network Open.
University of Washington at Seattle researchers led the secondary analysis of 1,410 participants in three completed randomized COVID-19 clinical trials. They compared two remote trials with a traditional clinic-based study that took place at the same time from March to August 2020, using Google Analytics data to measure online participant engagement and recruitment. The team analyzed data from April to August 2021.
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The two remote studies involved early COVID-19 treatment and the use of hydroxychloroquine as postexposure prophylaxis, respectively, and the clinic-based trial focused on expanded access to convalescent plasma as a treatment. All three studies had clinical sites in Seattle, and the remote trials also had sites in New York, Maryland, Massachusetts, Illinois, Louisiana, and California.
The remote trials used ads on Facebook, Google, Twitter, and Reddit that featured racial and ethnic minorities to enroll 929 participants with recent COVID-19 exposure and 231 participants who tested positive for the virus. Visits were completed through telemedicine, and enrollees recorded medication use and symptom data in an electronic database. The researchers tailored the approach weekly using ZIP code–based COVID-19 incidence rates.
The clinic-based study used clinician referral to recruit 250 participants with recent COVID-19 infection for in-person visits. Average participant age was 39 years in the remote trials and 50 in the clinic-based study.
The early-treatment study enrolled 231 participants in 41 states. Of 228 participants in the trial with available race data, 17.1% were Alaska Native or American Indian (vs 0.4% in the 250-participant clinic-based study), 4.8% were Asian (vs 8.8%), 11.4% were Black (1.6%), 1.3% were Native Hawaiian or Pacific Islander (0.004%), 51.3% were White (85.6%), and 14.0% were of another race (3.2%).
Of 230 participants in the early-treatment study with available ethnicity data, compared with 236 in the clinic-based study with available ethnicity data, 30.9% versus 4.7% were Hispanic or Latino. While 12.6% of enrollees in the early-treatment trial lived in nonurban areas, only 2.4% in the clinic-based trial did so.
Better generalizability, fewer disparities
The highest participant engagement in the remote trial online recruitment was with ads on social media platforms. Of 125,147 unique users with available age who clicked on online recruitment ads, 67.3% did so through Facebook.
A total of 10,455 online users clicked through the ad to access the prescreening survey (7.5%), and 9.7% of them (605 of 6,232) were 18- to 24-year-old Facebook users. Clinician referrals to the study website and linked referrals from personal social media posts were rare.
Remote-trial participants lived a median of 19 miles from each trial site, and clinic-based enrollees were a median of 11 miles away.
The researchers noted the disproportionate burden of COVID-19 infections and deaths on racial and ethnic minorities. They said that a lack of trust resulting from longstanding societal marginalization and mistreatment of Black, Hispanic, and Indigenous participants is tied to underrepresentation of these groups in clinical trials. Problems with proximity to trial sites, lack of transportation, and time flexibility may also contribute to this disparity.
"Racial and ethnic diversity among study participants is associated with improved generalizability of clinical trial results and may address inequities in evidence that informs public health strategies," they wrote. "Further work is needed to make clinical research more inclusive and address structural racism and the urban-rural divide that impact access to clinical trials."
