Although she believes quantitative, unbiased scientific studies on the California ratio experience will validate a reduction in adverse events, McEwen says that nurses "feel that their ability to provide safer care is protected because they have a ratio law in place."
She adds, "Increased moral distress and greater job dissatisfaction in nurses are strongly and significantly associated with high patient-to-nurse ratios when nurses are unable to provide the comprehensive care patients need."
She and other ratio advocates point to a 2002 study, published in the Journal of the American Medical Association, which said hospitals can "avert both preventable mortality and low nurse retention in hospital practice" by increasing the number of nurses.
The author Linda Aiken, of the Center for Health Outcomes and Policy Research, wrote: "Higher emotional exhaustion and greater job dissatisfaction in nurses were strongly and significantly associated with patient-to-nurse ratios."
"We're looking forward to a reputable study in California, similar to Aiken's and others, that show that complication rates can be reduced by having nursing ratios in place," McEwen says.
Studies of the actual California experience since the ratios were implemented have not produce conclusive results.
An issue brief published by the California Healthcare Foundation 11 months ago looked at the impact of the ratios on safety measures, such as failure to rescue, post-operative sepsis, pneumonia mortality, deep vein thrombosis, and decubitus ulcers.
"Many of the health care leaders interviewed for the study expressed an expectation that the minimum staffing ratios would increase the quality of care due to increased interaction with patients; however, there was no evident change in patient length of stay or adverse patient safety event," the report said.
It added that hospital administrators interviewed for the study "found that it was (a) challenge to meet the staffing requirements, particularly in ensuring that staff were available at all times, including during breaks and meals."
Additionally, hospital officials "reported difficulties in absorbing the costs of the ratios, and many had to reduce budgets, reduce services, or employ other cost-saving measures," the authors wrote.
However, the report, prepared by Joanne Spetz and colleagues at the Center for California Health Workforce Studies at the University of California San Francisco, said that the minimum nurse staffing regulations did achieve one goal of the legislation: skill mix increased in California hospitals.
"The hours worked per patient by RNs and registry RNs significantly increased," the study said.
The authors acknowledged that "more detailed analysis of this and other nursing-sensitive outcomes is needed to fully explore the effect of nurse staffing ratios on the quality of patient care."