Introduction. In the last 15 years the amount of studies on missed nursing care has increased, highlighting the global dimensions of this phenomenon. Objective. To identify (a) the terms and the conceptual models currently available; (b) the measurement tools validated in the field of missed care both at the international and at the national levels. Method. In December 2017 a literature search was conducted by accessing Cochrane Library, MEDLINE, CINAHL, Scopus and Web of Science databases. The search provided 819 results; after removing duplicates, 273 abstracts were evaluated and 33 studies included. Results. In the field of missed care, three main approaches have been developed to date: (a) Tasks Undone (TU), (b) Implicit Rationing (IR) and (c) Missed Nursing Care (MC). Each of these approaches has used different definitions, conceptual frameworks and measurement tools and has originated in different contexts. Those studies conducted in Italy have been performed mostly within the MC approach, by adopting the same definition, conceptual framework and instrument. Conclusions. Overall the missed nursing care definition, its conceptual model and the MISSCARE survey tool reflect the most widespread approach in the field, both at the international and Italian levels. There is a need to develop a common theoretical approach, definition and tool aimed at increasing the consistency of evaluations as well as the opportunity of international comparisons
