August 28, 2025
3 min read
Key takeaways:
- None of the eligible trials received a “good” diversity rating for race and ethnicity.
- Access-related barriers and low clinical awareness contribute to limited trial participation.
Diverse patient groups are notably absent in systemic lupus erythematosus clinical trials whereas white patients are overrepresented, according to a study published in Arthritis Care & Research.
Black, Asian and Latino populations are among high-risk populations for SLE, according to the researchers. Poor representation of these groups in clinical trials is often tied to access barriers, which can lead to a worsened quality of life and higher mortality rates, they added.

“On the surface, there are practical and logistical barriers that prevent many people from even participating in clinical trials, such as geographic access, lack of reliable transportation, inadequate insurance coverage and limited awareness,” Seth Sims, a medical student at Oklahoma State University Center for Health Sciences, and lead author of the study, told Healio. “Our goal was to evaluate how closely lupus trial demographics reflect the real-world disease burden.”
Underrepresentation across studies
Sims and colleagues conducted a systematic review and meta-analysis of the MEDLINE and Embase databases for clinical trials evaluating SLE interventions. They identified 18 clinical trials published between 2018 to 2023 that met their inclusion criteria, 66.7% of which were funded by industry and 55.6% of which included sample sizes of fewer than 50 patients.
Using the Clinical trial Diversity Rating framework, the researchers evaluated the racial and ethnic group representation of the trials. They gave the studies a value using the Participation-to-Disease Representation Ratio (PDRR) measurement, which compared patient demographics to the prevalence of the disease, ranging from overrepresented (PDRR > 1.2) to underrepresented (PDRR < 0.8) and adequately represented (PDRR 0.8). Based on the PDRR, the researchers gave each trial a finalized total representation score of poor, fair or good.
Overall, their results showed that despite men being underrepresented in two-thirds of the studies (66.7%), male and female demographic representation appropriately illustrated the general SLE patient population.
However, the researchers rated the representation for race and ethnicity as “poor” in more than half of the studies (61.1%), with none receiving a “good” rating. Black, Asian and Latino populations demonstrated poor representation across studies, including two studies (11.1%) with significant underrepresentation and 14 studies (77.8%) with underrepresentation that did not reach statistical significance.
Notably, Black patients were among the most underrepresented across 10 studies (PDRR < 0.8), whereas white patients were overrepresented in a majority 14 studies (PDRR > 1.2).
Due to the lack of age band data in the studies, the researchers could not assess them for their inclusion of older adults.
Strategies to increase trial diversity
“We expected to find disparities, but we were surprised by the extent and consistency of underrepresentation,” Sims said.
Although the findings indicate representation remains a prominent issue, few trials have taken steps to integrate diversity measures into clinical recruitment, according to Sims.
“Trials often just reflect the communities closest to these large academic or research institutions, which in the United States often means white, urban, higher income populations,” he said. “It’s probably unintentional, but diversity suffers when outreach doesn’t get beyond those walls.”
Sims noted that refined recruitments strategies start with clinicians, who can improve awareness and education of clinical trials and SLE treatment.
“One of the most powerful things a clinician can do is talk to their patients about trial opportunities and reassure them that participating doesn’t mean being a guinea pig; it means getting access to potentially helpful treatment and contributing to future care,” he said. “Advocating for your underserved population, trying to remove some of those financial or logistical barriers, and being knowledgeable about new clinical trials can help with that.”
Sims said future research should focus on “establishing community partnerships and culturally tailored outreach” to provide greater insight into trial shortcomings and improving patient outcomes.
“Accurate representation in a clinical trial isn’t just a regulatory box to check,” he added. “It directly impacts the safety and effectiveness of care, especially for lupus, which presents differently for different racial and ethnic populations. We run the risk of developing treatments that work well in theory but might not meet the needs of everybody in practice.”
For more information:
Seth Sims can be reached at seth.sims.research@gmail.com.