2 - (IOP 39) Racial and Ethnic Disparities in Study Exclusion: Evidence from a Randomized Trial for Prenatal Insomnia

Background: Eligibility criteria are a critical component of a well-designed clinical trial, enhancing trial safety and internal validity. Yet, data suggest that these criteria may disproportionately exclude minoritized people, potentially limiting diversity in study populations and reducing generalizability. This study compared inclusion and exclusion rates across seven racial or ethnic groups in a randomized from participation in a randomized controlled trial (RCT) testing two digital sleep interventions for prenatal insomnia.

Method: Prospective pregnant participants (n=4,235) took a study eligibility survey and provided demographic data. Nine 2x7 chi-squared tests were conducted to compare the proportion of each racial/ethnic group excluded at screening a) overall, and b) due to eight independent exclusion criteria. Post-hoc analyses stratified chi-square tests by adjusted household income (above or below $50,000) to test whether income would attenuate ethnic or racial differences.

Results: Overall, Multiracial participants (most who were Black and another race) were excluded at the highest rates (60.4%), while Latina participants were excluded at the lowest rates (48.0%). Further, the proportion of excluded participants differed by race or ethnicity across all eight exclusion criteria. For example, Latina Black participants were disproportionately likely to be excluded due comorbid conditions like bipolar disorder X^2 (6, N = 4,151) = 33.28, p < .001 or sleep apnea X^2 (6, N = 4,151) = 20.94, p =.002, while Asian participants were disproportionately likely to be excluded for having subclinical insomnia symptoms X^2 (6, N = 4,151) = 85.99, p < .001. White participants were most likely to be excluded due to antidepressant medication use X^2 (6, N = 4,151) = 100.06, p < .001. Most racial and ethnic differences in exclusion persisted after controlling for adjusted household income.

Conclusions: Exclusion criteria disproportionately impact individuals based on race/ethnicity. Disparities in trial exclusion based on medical or psychiatric comorbidities and can contribute to the under-enrollment of minoritized pregnant people in RCTs for behavioral health, especially those who are Black. Examining racial and ethnic differences in eligibility criteria can identify demographic groups that ought to be screened at greater numbers to enhance the likelihood of obtaining a representative sample. This data-driven strategy can be leveraged to improve participant diversity in RCTs and promote more equitable clinical practice.