Background: Responding to research confirming the link between
nurse staffing and patient outcomes, 14 states have introduced
legislation to limit patient-to-nurse ratios. However, increased staffing places a considerable financial burden on hospitals.
Objective: We sought to determine the cost-effectiveness of various
nurse staffing ratios.
Research Design: This was a cost-effectiveness analysis from the
institutional perspective comparing patient-to-nurse ratios ranging
from 8:1 to 4:1. Cost estimates were drawn from the medical
literature and the Bureau of Labor Statistics. Patient mortality and
length of stay data for different ratios were based on 2 large hospital
level studies. Incremental cost-effectiveness was calculated for each
ratio and sensitivity and Monte Carlo analyses performed.
Subjects: The study included general medical and surgical patients.
Measures: We sought to measure costs per life saved in 2003 US
dollars.
Results of Base Case Analysis: Eight patients per nurse was the
least expensive ratio but was associated with the highest patient
mortality. Decreasing the number of patients per nurse improved
mortality and increased costs, becoming progressively less costeffective as the ratio declined from 8:1 to 4:1. Nonetheless, the
incremental cost-effectiveness did not exceed $136,000 (95% CI
$53,000–402,000) per life saved.
Results of Sensitivity Analysis: The model was most sensitive to
the effects of patient-to-nurse ratios on mortality. Lower ratios were
most cost-effective when lower ratios shortened length of stay, and
hourly wages were low. However, throughout the ranges of all these
variables, the incremental cost-effectiveness of limiting the ratio to
4:1 never exceeded $449,000 per life saved.