The use of complexity theory to inform antimicrobial stewardship: a scoping review.

BACKGROUND:Complexity theory has previously been used as a conceptual lens in human healthcare research. Antimicrobial stewardship (AMS) is an inherently complex healthcare intervention; however, the extent to which complexity has been operationalized in AMS is currently unclear. AIM:To investigate if, and how, complexity theory has been used to inform AMS in human healthcare. METHODS:Scoping review methodology. Empirical research or policy specifically referencing complexity in relation to AMS were considered in any human healthcare setting and geographical location. Databases searched were: Cinahl, Cochrane Library, Embase, Medline, National Institute for Health and Care Excellence, PsycInfo, Scopus and Web of Science from inception to June 2020. Grey literature and other databases searched: EVIPNet, Google, Mednar, Proquest Theses, and the World Health Organization library of national antimicrobial resistance action plans. Non-English language articles were excluded. RESULTS:Of 612 records retrieved, 8 articles were included. Heterogeneity in study design and geographical location were noted. Three interventional studies evaluated AMS in hospital (n = 2) and long-term care (n = 1) settings. Remaining studies were non-interventional and proposed AMS strategies conceptualized through complexity theory. The importance of close engagement between researchers or policy administrators and the target population was emphasized in all studies, as a means of ensuring AMS relevance and success. CONCLUSIONS:There is a paucity of AMS research informed by complexity theory, and no policy documents could be located using complexity as a guiding theory. Mixed methods, informed by complexity theory, is a potentially suitable strategy to develop, implement and evaluate AMS as a complex intervention.