Strengthening health research capacity for postgraduate trainees: an indigenous realist evaluation of the 'African Research Initiative for Scientific Excellence' programme.

International research partnerships are crucial to strengthening research capacity (RCS) efforts. However, little is known about how such partnerships work to enhance the capacity of postgraduate trainees. We applied an Indigenous realist evaluation (RE) approach to examine how the 'African Research Initiative for Scientific Excellence' (ARISE) programme works to strengthen the capacity for trainees. The Indigenous RE integrates critical and scientific realism paradigms with the Postcolonial Indigenous paradigm, focusing strongly on power, relationality, and decolonization. We used a multi-case study design to investigate two cases of innovation- and laboratory-based research projects led by African principal investigators (PIs). We conducted realist-informed interviews and observations with PIs, interviews with collaborators and partners, and storytelling with students. Realist thematic analysis helped to identify context, intervention, mechanism, and outcomes (CIMO). Deductive, inductive, abductive, and retroductive reasoning were applied to generate programme theories through an iterative and rigorous theory-building process. Findings show that trainees who are committed and self-driven, based in a research-intensive university that provides complementary opportunities and where there is demand for multidisciplinary research, will improve their skills, secure additional funding, and transition from master's to PhD programmes. This is because the RCS resources would inspire, challenge, empower, activate a sense of agency, and provide the trainees with eye-opening experiences. However, trainees would secure jobs outside Africa (brain drain) if career opportunities in specialized fields are limited locally. If trainees are junior faculty staff and fully funded, and their university provides protected time, RCS resources would inspire, motivate, and empower them, resulting in increased research outputs and career growth. RCS efforts targeting (post)graduate trainees need to consider 'inter alia' the university contexts (e.g. availability of complementary resources and protected time), the individual traits and readiness for postgraduate training, and the broader ecosystem, which determines if the trainees' skills benefit Africa's research and development.