title: California's minimum nurse staffing legislation: results from a natural experiment.
abstract: OBJECTIVE
  To determine whether, following implementation of California's minimum nurse staffing legislation, changes in acuity-adjusted nurse staffing and quality of care in California hospitals outpaced similar changes in hospitals in comparison states without such regulations.
  
  
  METHODS
  Data from the American Hospital Association Annual Survey of Hospitals, the California Office of Statewide Health Planning and Development, the Hospital Cost Report Information System, and the Agency for Healthcare Research and Quality's Health Care Cost and Utilization Project's State Inpatient Databases from 2000 to 2006.
  
  
  METHODS
  We grouped hospitals into quartiles based on their preregulation staffing levels and used a difference-in-difference approach to compare changes in staffing and in quality of care in California hospitals to changes over the same time period in hospitals in 12 comparison states without minimum staffing legislation.
  
  
  METHODS
  We merged data from the above data sources to obtain measures of nurse staffing and quality of care. We used Agency for Healthcare Research and Quality's Patient Safety Indicators to measure quality.
  
  
  RESULTS
  With few exceptions, California hospitals increased nurse staffing levels over time significantly more than did comparison state hospitals. Failure to rescue decreased significantly more in some California hospitals, and infections due to medical care increased significantly more in some California hospitals than in comparison state hospitals. There were no statistically significant changes in either respiratory failure or postoperative sepsis.
  
  
  CONCLUSIONS
  Following implementation of California's minimum nurse staffing legislation, nurse staffing in California increased significantly more than it did in comparison states' hospitals, but the extent of the increases depended upon preregulation staffing levels; there were mixed effects on quality.
authors.affiliation: School of Nursing, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. bmark@email.unc.edu
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Mark
authors.forename: David W
authors.initials: DW
authors.lastname: Harless
authors.forename: Joanne
authors.initials: J
authors.lastname: Spetz
authors.forename: Kristin L
authors.initials: KL
authors.lastname: Reiter
authors.forename: George H
authors.initials: GH
authors.lastname: Pink
mesh_terms: D002140:California; D003428:Cross Infection; D006302:Health Services Research; D006739:Hospital Administration / Q000331:legislation & jurisprudence*; D006801:Humans; D009741:Nursing Staff, Hospital / Q000331:legislation & jurisprudence* / Q000458:organization & administration; D010561:Personnel Staffing and Scheduling / Q000331:legislation & jurisprudence* / Q000458:organization & administration; D019984:Quality Indicators, Health Care; D011787:Quality of Health Care / Q000458:organization & administration* / Q000706:statistics & numerical data*; D014481:United States; D016270:United States Agency for Healthcare Research and Quality; D016526:Workload / Q000331:legislation & jurisprudence