Levels of care: the impact of nurse-patient ratios.
D002140:California; D006801:Humans; D007882:Legislation, Hospital; D009741:Nursing Staff, Hospital / Q000331:legislation & jurisprudence / Q000600:supply & distribution*; D010561:Personnel Staffing and Scheduling / Q000331:legislation & jurisprudence*; D011787:Quality of Health Care; D006113:United Kingdom; D014739:Victoria