BackgroundWith the integration of quality improvement (QI) into competency-based models of physician training, there is an increasing requirement for medical students and residents to demonstrate competence in QI. There may be factors that commonly facilitate or inhibit the desired outcomes of QI curricula in undergraduate and postgraduate medical education. The purpose of this review was to synthesise attributes of QI curricula in undergraduate and postgraduate medical education associated with curricular outcomes.MethodsA realist synthesis of peer-reviewed and grey literature was conducted to identify the common contexts, mechanisms, and outcomes of QI curricula in undergraduate and postgraduate medical education in order to develop a programme theory to articulate what works, for whom, and in what contexts.Results18854 records underwent title and abstract screening, full texts of 609 records were appraised for eligibility, data were extracted from 358 studies, and 218 studies were included in the development and refinement of the final programme theory. Contexts included curricular strategies, levels of training, clinical settings, and organisational culture. Mechanisms were identified within the overall QI curricula itself (eg, clear expectations and deliverables, and protected time), in the didactic components (ie, content delivery strategies), and within the experiential components (eg, topic selection strategies, working with others, and mentorship). Mechanisms were often associated with certain contexts to promote educational and clinical outcomes.ConclusionThis research describes the various pedagogical strategies for teaching QI to medical learners and highlights the contexts and mechanisms that could potentially account for differences in educational and clinical outcomes of QI curricula. Educators may benefit from considering these contexts and mechanisms in the design and implementation of QI curricula to optimise the outcomes of training in this competency area.