Background:
Healthcare-related research institutions are working to increase diversity among their researchers and staff. However, data on effective practices to grow and support a diverse health services research (HSR) workforce is sparse. Our study objective was to identify, describe, and evaluate practices that enhance hiring, promotion, and retention of employees from underrepresented groups (URGs) (such as race/ethnicity, gender identity, disabilities) in the HSR workforce.

Methods:
US Veterans Health Administration (VHA) oversees hospitals, health care clinics, and research centers. We reviewed the websites of VHA Centers of Innovation (COIN) research centers and documented practices to increase the hiring, promotion, and/or retention of URG employees. Additionally, we conducted semi-structured interviews with research center representatives to gather information on diversity, equity, and inclusion (DEI) practices, outcome measures, and barriers and facilitators to implementation and sustainment.

Results:
Several themes emerged. For _hiring_, funding fellows and scholars from URGs often led to the hiring of trainees from URGs. In the area of _retention_, anti-racism/diversity trainings, mentoring programs, and DEI advisory groups contributed to a culture welcoming to URG researchers. _Promotion_ often entailed mentoring initiatives to assist staff and investigators with career advancement. _Sustainment_ of DEI was supported by financial resources (e.g. providing attractive start-up packages to URG candidates), institutional leadership support, and sharing of DEI responsibilities among staff and investigators across the institution. Barriers to sustainment included lack of financial resources, faculty/staff resistance to change, and burnout among individuals leading DEI initiatives. Measurement of DEI progress often involved surveys of research center employees to understand institutional climate and contributors to negative perceptions, such as micro-aggressions.

Conclusions:
Initiatives to improve workforce diversity within VHA COIN research centers are common. However, hinderances include lack of staffing of DEI positions, insufficient financial resources, and inadequate leadership support. Additionally, much progress is needed in effective measurement of diversity activities.