The results of a new study indicate there is a correlation between nurse understaffing and elevated healthcare-associated infection risk.

The study, published in The Journal of Nursing Administration, analyzed multiple data sets gathered over a period of several years from an urban hospital system.

The key finding: When nurse understaffing occurred (defined as below 80% of unit median) on a unit for both shifts (day and night) in a day, patients on those units were much more likely to develop a healthcare-associated infection (HAI) two days later.

The researchers' conclusions include the following: "… a break of continuous care due to nurse understaffing will directly affect patient outcomes. In addition, a continuous unit staff shortage may also indicate an underlying issue with the working environment. Nurse administrators need to implement effective solutions to ensure adequate nurse staffing and provide safe and reliable care to acutely ill hospitalized patients."

The project received approval from Columbia University Medical Center and Weill Cornell institutional review boards.