Background: Health research capacity strengthening (HRCS) has been deemed as a complex, multifaceted, and dynamic activity. Despite this, most studies that assess the effectiveness of health research capacity strengthening programmes have not employed complexity-aware approaches and therefore, evidence on how and why such programmes work across different contexts is underdeveloped. This realist study seeks to elicit the initial programme theories (IPTs) that describe how and why the ‘Developing Excellence in Leadership, Training and Science Africa’ (DELTAS Africa) programme – one of the flagship research capacity strengthening programmes in Africa – works to generate research capacity outcomes specifically in the participating African universities. Methods and Analysis: A realist review of the DELTAS Africa programme documents, and relevant published papers that report on similar research capacity interventions will be carried out. This will help to both identify the outcome pathways and underlying assumptions of the DELTAS Africa programme, as well as tacit theories as postulated by other researchers. The review evidence will inform the drafting of the initial programme theories (IPTs). Interviews with the DELTAS Africa programme designing team will be conducted using a realist interviewing technique to unearth ontologically deeper insights on context, mechanism, and outcomes. Using the realist context-mechanism-outcome configurational maps, we will identify how contexts (i.e., within the African universities) shape mechanisms (the processes, reasoning, or behaviours triggered by the HRCS activities) through which the programme brings about an outcome at institutional level. Conclusion: The initial programme theories will describe how and why health research capacity strengthening works, for whom and under what circumstances across the participating African universities. The programme theories will provide policy-relevant insights on the generative causal mechanisms of HRCS; evidence that is critically needed to inform the design, implementation, and evaluation of HRCS initiatives.
