Eileen T. Lake, PhD, MSN, MA, BSN, FAAN

Eileen T. Lake, PhD, RN, FAAN

Professor of Nursing

Edith Clemmer Steinbright Professor in Gerontology

Professor of Nursing and Sociology

Associate Director, Center for Health Outcomes and Policy Research

Editor, Research in Nursing and Health

With training in nursing administration, public policy, and sociology, Eileen T. Lake developed a foundational measure of nursing care performance to demonstrate nursing’s impact on patient outcomes: the Practice Environment Scale of the Nursing Work Index.

Endorsed by the National Quality Forum, the index provides scientific evidence that health care settings that capitalize on nurses’ education and skills by providing competent and supportive managers, expecting physicians to treat nurses as partners in care, providing sufficient staff and resources, and encouraging nurse input on decisions achieve higher quality outcomes. Dr. Lake’s goal with the index, which is used in over 23 languages, is to motivate managers and policymakers to make nursing resources a priority investment.  

Magnet® Status, Nurse Staffing, and Patient Falls 

Dr. Lake’s study of nurse staffing in Magnet® hospitals contributed to U.S. News & World Report adding Magnet® status as a criterion in its America’s Best Hospitals designation in 2004. The American Nurses Credentialing Center confers Magnet® status on hospitals meeting high standards for patient care, nursing excellence, and innovations in professional nursing practice.  In her retrospective study of 5,388 nursing units in 108 Magnet® and 528 non-Magnet® hospitals, Dr. Lake found that the patient fall rate was five percent lower in Magnet® than non-Magnet® hospitals, after adjusting for patient characteristics such as age and gender. 

I endeavor to demonstrate that nursing is vital to health and that fostering supportive work environments is wise policy to maximize nursing’s impact.


  • PhD, University of Pennsylvania, 1999
  • MSN, University of Pennsylvania, 1997
  • MA, Georgetown University, 1986
  • BSN, Duke University, 1981


With support from the NIH and the Robert Wood Johnson Foundation, Dr. Lake and her research team conducted multiple studies on national samples of neonatal intensive care units (NICUs).  One study used data on 70,000 very-low-birth-weight infants (less than three pounds, five ounces) in Magnet® and non-Magnet® hospitals. The team found that 13 percent of these infants die during their hospitalization, and that deaths were 1 to 2 percent lower in Magnet® hospitals than in non-Magnet® hospitals. Each percentage point accounts for about 300 infants nationally. 

Very-low-birth-weight infants born in hospitals with high concentrations of black newborns also had higher rates of infections and discharge without breast milk. The team concluded that, “improvements in nursing have potential to improve the quality of care for seven out of ten black very-low-birth-weight infants born each year.” 

To evaluate NICU nurse staffing levels nationally, Dr. Lake’s team developed definitions for five infant acuity levels in neonatal intensive care and used these definitions in data from 6,060 nurses in 104 U.S. NICUs. The researchers documented widespread understaffing of NICUs relative to national guidelines, and showed that understaffing is strongly associated with premature infants developing infections. NICUs were understaffed for one third of all infants and 68 percent of the most complex, unstable infants.  This work prompted the National Database of Nursing Quality Indicators to add the infant acuity definitions to the annual Registered Nurse Survey in 2016. 

Opportunities to Learn and Collaborate at Penn Nursing

Dr. Lake teaches one undergraduate course that integrates research methods with evidence-based practice and another that compares the health systems of the U.S. and Chile. As associate director of the Center for Health Outcomes and Policy Research, Dr. Lake co-directs an interdisciplinary research and training program, mentors pre- and post-doctoral students, and supervises undergraduate students as research assistants.

Selected Career Highlights

  • Distinguished Alumna Award, Duke University School of Nursing  
  • International Consultant, Editorial Board, Metas de Enfermeria 
  • Best Abstract Award, 2009, American Organization of Nurse Executives  
  • At-Large Member, Nursing Advisory Council, Joint Commission on Accreditation of Healthcare Organizations  
  • Research Mentor Award, 2014, AcademyHealth Interdisciplinary Research Group on Nursing Issues

Accepting Mentees?

  • Yes

Accepting Fellows?

  • Yes

Featured Publications

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Revolutionizing Nurse Work Environment Research

New research from Penn Nursing’s Center for Health Outcomes and Policy Research (CHOPR) – recently published online in the journal Research in Nursing & Health – has successfully validated a new, streamlined version of the Practice Environment Scale of the Nursing Work Index (PES-NWI), originally authored in 2002 by Eileen T. Lake, PhD, RN, FAAN, Professor of Nursing, the Edith Clemmer Steinbright Professor in Gerontology, and Associate Director of CHOPR, who is also lead author on this publication. This innovative tool, known as the PES-5, is designed to revolutionize how nurse work environments are measured across the United States.

Read MoreRevolutionizing Nurse Work Environment Research