Bridging the Gap: Culturally Responsive Strategies for NIH Trial Recruitment

To enhance recruitment and participation rates of non-Hispanic Black (NHB) and Hispanic adult patients in a NIH-funded clinical trial studying an emerging health technology.

This study includes primary data collected in Los Angeles, California from November 2020 through November 2023.

To improve the representation of NHB and Hispanic patients in a NIH-funded (NCT04409353) trial on virtual reality for chronic lower back pain (cLBP), we conducted a multi-phase study utilizing a mixed-method approach. First, we conducted focus groups with NHB and Hispanic cohorts aged 18 and older; based on the feedback, we culturally adapted recruitment materials and study correspondences concordantly. Additionally, a cohort builder was used to filter the electronic medical record to isolate non-Hispanic Black (NHB) and Hispanic patients with cLBP for micro-targeted recruitment. These changes were collectively integrated when the parent NIH study had recruited 222 of its 385 final samples (57.7%), creating a pre-post comparison timepoint (May 17, 2022). Quantitative analysis was performed to assess the efficacy of the modified recruitment strategies by comparing the number of recruited and randomized NHB and Hispanic patients pre- and post-intervention.

Semi-structured focus groups were conducted with NHB and Hispanic patients and community members (age 18 and older). The focus groups were conducted online and recorded with participant consent; transcripts of the recording underwent inductive thematic analysis. Emergent themes directed the modification of study materials, including revised language and imagery, targeted outreach, and incorporation of treating physicians, were implemented in the second half of the study. Quantitative analyses were conducted following parent study completion by comparing records added to the screening database following the implementation of new recruiting methods (5/17/2022) to those added before.

Thematic analysis of focus groups identified four key themes: mistrust, lack of interest, culture, and communication. Modifications to recruitment methodology resulted in statistically significant increases in the pre- to post-randomization success rate for the overall study population (p < 0.001), the NHB population (p = 0.011), and the Hispanic population (p < 0.015). When looking at each cohort at different points in the recruitment process before and after the intervention, in the Hispanic population, we saw significant increases in the number approached (p < 0.001) and number randomized (p < 0.001) and statistically insignificant increases in the NHB population approached (p = 0.067) and randomized (p = 0.295). Similarly, we saw that the changes in the recruitment letter led to a statistically significant increase in Hispanic recruitment (7.0 to 39.1%, p < 0.001) but not the NHB cohort (19.6 to 35.8%, p < 0.065).

This study introduces several culturally sensitive considerations and possible approaches for the design of recruitment materials, addressing mistrust, lack of interest, culture, and communication for use in NHB and Hispanic populations. Similarly, the described microtargeting techniques leverage the technological advancements in cohort building to improve the reach and efficiency of the randomization rate of underrepresented groups thereby enhancing clinical trial diversity.