Her study compared patient outcomes data reported by hospitals to state agencies and surveyed 22,236 hospital staff nurses in those three states. The report was long anticipated because California remains the first and only state to implement minimum nurse-patient staff ratios in its acute care hospitals, as of Jan. 1, 2004.
The law says a nurse must care for no more than five patients on a medical-surgical unit, four pediatric patients, two in intensive care, six in a psychiatric unit, and three in labor and delivery.
According to a table in Aiken's report, adjusted 30-day inpatient mortality in California was also significantly lower than in New Jersey or Pennsylvania.
Also, Aiken reported, 88% of nurses surveyed in a medical-surgical unit reported having five patients, but in New Jersey only 19% and in Pennsylvania only 33% reported those ratios. The rest had higher ratios.
Similar disparities were seen for nurses working in intensive care, telemetry, oncology, labor and delivery, and pediatric units, according to Aiken's report.
Aiken's surveys of nurses in those three states revealed that in California, nurses had better job satisfaction, less burnout, and said they provided better quality of care than did nurses who responded in Pennsylvania and New Jersey. "California nurses were more likely to rate quality of care as excellent than nurses in the other two states," she says.
Aiken's report from 2002 found that each patient added to a nurse's workload added 7% to the mortality rate for patients undergoing common surgeries. Also, she reported, higher nurse to patient ratios were also associated with more nurse burnout, job dissatisfaction, and precursors of voluntary turnover.
Since 2004, the state has increased the number of actively licensed RNs by more than 110,000, tripling the average annual increase before 1999 when the law was enacted, and five years before it took effect.
"From a policy perspective, our findings are revealing," Aiken wrote in her conclusion. "The California experience may inform other states that are currently debating nurse ratio legislation."