What was this review about?
Concerns about patient safety and the quality of care are driving research on the clinical and cost-effectiveness of health care interventions, including the deployment of human resources.
This is particularly important in intensive care where a large proportion of the health care budget is consumed and where nursing staff is the main item of expenditure.
Recommendations about staffing levels have been made but may not be evidence based and may not always be achieved in practice.
This review looked at studies conducted in critical care settings that allowed data on one or more nursing workforce variables to be related to mortality or adverse events. All study designs were included.
What did the review find?
The review identified 15 eligible studies. Studies were mainly observational and retrospective and varied in scope from one to 52 critical care units.
Of ten studies that evaluated a relationship with adverse events, all ten reported a relationship.
Of ten studies that evaluated a relationship with mortality, only three found a significant relationship.
The authors recommended that future research should include developing the mechanisms linking nursing resources to patient outcomes and designing large multicentre prospective studies that link patients’ exposure to nursing care on a shift-by-shift basis over time.