Understanding health systems as comprising interacting elements of hardware and software acknowledges health systems as complex adaptive systems (CASs). Hardware represents the concrete components of systems, whereas software represents the elements that influence actions and underpin relationships, such as processes, values, and norms. As a specific call for research on health system software was made in 2011, we conducted a qualitative scoping review considering how and for what purpose the concept has been used since then. Our overall purpose was to synthesize current knowledge and generate lessons about how to deepen research on, and understanding of, health system software. The review consisted of two phases: first, for the period 2011-23, all papers that explicitly used the concept of health system software were identified and mapped; second, drawing on a subset of papers from Phase 1, we explored how the concept was purposively used within research. The databases PubMed, Scopus, EBSCOhost, Web of Science, and Google Scholar were systematically searched using a strategy developed by a skilled librarian. In Phase 1, data were extracted from 98 papers. Our analysis revealed that a third of the papers used the software concept rather superficially; a third used it to conceptualize the importance of selected software elements; and a third used it in examining a specific health system experience, such as preparedness or resilience. In Phase 2, our analysis confirmed that researchers have found value in proactively using the software concept within studies, demonstrating two patterns of use. However, a limited understanding of how to investigate interactions among hardware and software elements was also revealed. Future health policy and systems research should purposively investigate hardware-software interactions in order to gain a greater understanding of the complex, adaptive nature of health systems, understand their operations, and institutionalize thinking that considers health systems as CASs.
