Complexity of nursing care represents an important indicator in the planning and management of nursing resources and healthcare management. However, the term is not clearly defined in the literature. The aim of this article is to outline the main concepts associated with complexity of nursing care, trying to shed light on the different variables that constitute it. We conducted a review of the literature and selected 12 articles. The terms associated with the concept of complexity of nursing care include nursing intensity, nursing work, nursing workload, patient acuity and severity of illness. The literature review indicates that complexity of nursing care appears to be one of the variables of care intensity, the latter being defined as a commitment of care delivered to the patient. It is associated with the concepts of nursing work, nursing workload, patient acuity and severity of illness. Understanding and clarifying the concept of complexity of care is fundamental in order to measure and evaluate the real demand for nursing care by individual patients.
