By Paul Leigh, Ph.D.

California is the only state with a law governing minimum nurse-to-patient staffing ratios. The ratios vary depending on the type of hospital service but are in the range of one nurse for every five patients. (The ratios are available on the California Department of Public Health website.) The law went into effect in 2004.

Law was supposed to improve patient safety

Lawmakers and stakeholders intended that the law would improve patient safety as more nurses were employed to care for the same number of patients. Whereas many studies show improved patient safety after 2004, no consensus in the scientific literature has emerged.


My colleagues and I sought to answer a different question: could the law improve safety for the nurses themselves? We found that indeed the law did improve safety for nurses and the results were published in the May 2015 issue of the International Archives of Occupational and Environmental Health, “California’s Nurse-to-Patient Ratio Law and Occupational Injury”.

We began with the U.S. Bureau of Labor Statistics’ data set entitled the Survey of Occupational Injuries and Illnesses (SOII). The SOII collects annual data on nonfatal injuries and illnesses derived from 150,000 to over 200,000 private firms, depending on the year. We selected injury and illness data from 1999 to 2009 and combined with data on employment in hospitals in California and the rest of the US from the SOII and the California Employment Development Department. We applied the...Click here to read the rest of  the blog post.