A team of investigators looked at possible dementia clinical trial requirements that could exclude people based on race and ethnicity. Overall, 82% of the trials they examined had criteria that weren’t well-defined and could reduce diversity, according to a July 1 report in Scientific Reports. The authors said that the analysis was the first overview of eligibility criteria currently used in trials funded by the US federal government.
Researchers evaluated the eligibility criteria for 196 Alzheimer’s Disease and Related Dementias (AD/ADRD) trials funded by the National Institute on Aging from 2018 to 2023.
Clinical study criteria is important for clinical research because it helps ensure that the people enrolled in trials reflect the target population. This can reduce safety risks. But when criteria gets too restrictive, it can limit diversity in trials which can affect patient safety, the authors noted.
A 2022 National Academies of Sciences, Engineering, and Medicine (NASEM) report noted that eligibility criteria as a key barrier to equitable participation in clinical trials.
According to the recent study, the most frequent criteria cutoff was based on age, as was the case in 87% of trials. Other cutoffs included 65% based on neurological factors and 61% based on psychiatric disorders. Underrepresented groups could be disproportionately excluded by 16 eligibility categories, the authors noted. Specifically, 42% of trials would only accept people who spoke English.
Among all trials evaluated, there was an average of 15 eligibility criteria per trial, with Phase I/II drug trials listing the greatest number of criteria, the authors said.
“Ensuring eligibility criteria balance scientific need with equitable trial design is imperative to adequate representation in AD/ADRD clinical trials,” the authors wrote.
