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CHOPR Meet Our Research Fellows


Postdoctoral Fellows
Barnes_H_7_2014v2.jpgDr. Hilary Barnes (BA Skidmore College, 1997; BSN University of Pennsylvania, 2005; MSN Widener University, 2008; PhD Widener University, 2013) is a post-doctoral research fellow focusing on nurse practitioner role transition. She is nationally certified as a Family Nurse Practitioner, and her clinical background includes emergency nursing, surgery/surgical oncology, and addiction/behavioral health. Her dissertation is titled "A Study of Nurse Practitioner Role Transition Through Examination of the Specific Relationships of Desire for Feedback, Desire for Control, and the Number of Years of Prior Registered Nurse Experience."
Recent Publication:
  • Barnes, H. (2014). Nurse practitioner role transition: A concept analysis. Nursing Forum. doi:10.1111/nuf.12078
  • Barnes, H. (2015). Exploring the Factors That Influence Nurse Practitioner Role Transition. The Journal for Nurse Practitioners, 11, 178-183.


Dr. Karen Lasater (BSN Quinnipiac University, 2010; PhD University of Pennsylvania, 2015) is a post-doctoral researcher and a fellow at the Leonard Davis Institute of Health Economics. Dr. Lasater’s research interests include: (1) understanding how to organize nursing care to influence patient outcomes and promote safety, and (2) measuring how nurses add value within health care systems.

Selected Publications:

  • Lasater, K.B., Sloane, D.M., & Aiken, L.H. (2015). Hospital employment of supplemental registered nurses does not detract from patients’ overall hospital experience. Journal of Nursing Administration, 45(3), 145-151.
  • Brooks-Carthon, M., Lasater, K.B., Sloane, D.M., & Kutney-Lee, A. (2015). Omitted nursing care linked to heart failure hospital readmissions. British Medical Journal Quality and Safety, 24, 255-263.
  • Lasater, K.B. (2015, August 5). Surgeon scorecard: Are surgeons operating in a health care team. Retrieved from
  • Lasater, K.B. (2013). Invisible economics of nursing: analysis of a hospital bill through a Foucauldian perspective. Nursing Philosophy, DOI: 10.1111/nup.12040

jarin.Headshot.jpgDr. Olga Jarrín (BS, University of Connecticut, 2002; MS University of Connecticut, 2007; PhD University of Connecticut, 2010) is one of only a handful of scholars who has advanced the ontology and epistemology of nursing science. Her research focuses on improving community-based nursing for diverse older adult populations. Specifically, she examines multi-level, person-environment interactions impacting patient outcomes including health policy, socio-economic conditions, and healthcare work environments. 
Selected Publications:
  • Jarrín, O.F. (2006). Results from the Nurse Manifest 2003 Study: Nurses' Perspectives on Nursing. Advances in Nursing Science, 29(2), E74-E85.
  • Neafsey, P., Jarrín, O., Coffman, M. & Luciano, S. (2007). Self-Medication Behaviors of Spanish-Speaking Older Adults, Hispanic Health Care International, 5(4), 169-179.
  • Jarrín, O.F. (2007). An Integral Philosophy and Definition of Nursing. Journal of Integral Theory and Practice, 2(4), 79-101.
  • Jarrín, O.F. (2010). Core Elements of U.S. Nurse Practice Acts and Incorporation of Nursing Diagnosis Language. International Journal of Nursing Taxonomies and Classifications 21(4), 166-176.
  • Brooks Carthon JM, Kutney-Lee A, Jarrín O, Sloane DM, Aiken LH. (2012). Nurse Staffing and Post Surgical Mortality in Black Patients. Journal of the American Geriatrics Society.
  • Jarrín O.F. (2012). The Integrality of Situated Caring in Nursing and the Environment. Advances in Nursing Science 35(1), 14-24.  This is currently featured (free) on the ANS Journal website. LINK TO ARTICLE
  • Brooks Carthon JM, Jarrín O, Sloane D, Kutney-Lee A (2013). Variations in Postoperative Complications across Race, Ethnicity and Sex among Older Adults. Journal of the American Geriatrics Society, 61(9),1499-507.
  • O’Connor M, Bowles KH, Feldman P, St. Pierre M, Jarrín O, Shah S, Murtaugh C (2014). Frontloading and Intensity of Skilled Home Health Visits: A State of the Science. Home Health Care Services Quarterly, 33(3),159-175.
  • Jarrín O, Flynn L, Lake ET, Aiken LH (2014). Home Health Agency Work Environments and Hospitalizations. Medical Care, 52(9), 877-883.
  • Best K, Jarrín O, Buttenheim AM, Bowles K, Curley MA (2015). Innovation in creating a    strategic plan for research within an academic community. Nursing Outlook, 63, 456-461.
Dr. Jessica Rearden (BSN Cedar Crest College, 2000; MS University of Pennsylvania, 2010; PhD University of Pennsylvania 2014) is a post-doctoral researcher focusing on the influence of nursing care on cancer patient outcomes, eliminating cancer health disparities and improving opportunities for cancer clinical trial enrollment among under-represented groups.  Dr. Rearden’s clinical background is in oncology nursing and she has worked in bone marrow transplant, as a clinical research nurse and a clinical research nursing supervisor. Her dissertation, titled “Examining Opportunity for Cancer Clinical Trial Participation Among Under-represented Groups” was supported by a National Institute of Nursing Individual NRSA F31 (1F31NR01407601A1) and the American Nurses Foundation/Council for the Advancement of Nursing Science.
Selected Publication:
  • Rearden J, Hanlon A, Ulrich C, Brooks-Carthon M, Sommers M. (in press). Examining Differences in Opportunity and Eligibility for Cancer Clinical Trial Participation Based on Socio-Demographic and Disease Characteristics. Oncology Nursing Forum.
Predoctoral Fellows

Aparna Kumar is a third year pre-doctoral student. She holds a BA in political science from the University of Illinois, a BSN from the University of Pennsylvania, and an MSN in Psychiatric and Mental Health from the University of Pennsylvania School of Nursing. Prior to her doctoral studies, she worked as a neuroscience nurse, conducted research in sub-Saharan Africa, and worked in social services for children and families.  She is a board certified Psychiatric and Mental Health Nurse Practitioner and works in an outpatient setting. She is the co-author of several scientific papers. Her research interests include improving inpatient care outcomes, reducing readmissions for psychiatric patients, and implementing effective strategies for achieving mental health parity.
shweta2012.jpgShweta Singh is a second year pre-doctoral fellow at CHOPR. She completed her BSN and MSN in the Adult and Gerontology NP program at the University of Pennsylvania. Prior to starting the doctoral program, she worked as an oncology-certified, Level II clinical nurse in medical oncology at the Hospital of the University of Pennsylvania (HUP). As an RN, she actively participated in the Magnet Shared Governance council and assisted in the implementation of the electronic medical record at HUP. In her time at Penn, she presented class analyses on reform to Governor Rendell’s Office of Health Care Reform, was on the founding editorial board of the Journal of Student Nursing Research, and was inducted into the honor society Sigma Theta Tau International. She maintains an interest in international health and participated in the Penn Guatemalan Health Initiative as well as Penn tsunami relief efforts in Sri Lanka. Her researchinterests include nurse education, staffing, burnout, and the interaction of workplace environment, nursing care and patient outcomes. Her Center advisors are Dr. Linda Aiken and Dr. Ann Kutney-Lee.
Recent publication:
Singh, S. (2012). Entry into practice: Is it relevant today? [Letter to the editor]. American Nurses Association Online Journal of Issues in Nursing.
schierholz2.jpgElizabeth Schierholz is a first year pre-doctoral fellow. She holds a BSN from the University of Mary Hardin-Baylor and a MSN from the University of Pennsylvania. She is a board-certified Neonatal Nurse Practitioner. She also holds certifications in Neonatal and Pediatric Transport and as a Certified Medical Transport Executive. Elizabeth currently practices in a Level IV Neonatal Intensive Care Unit as a NNP in Philadelphia. Her previous experience includes work as a transport NNP in Denver, Colorado for AirLife Denver, and clinical practice as a NNP in several NICUs in San Diego, CA including Rady Children’s Hospital and Sharp Mary Birch Hospital for Women and Infants. Her research interests include quality outcomes of neonatal patients, safety and quality in handoff/transition of neonatal patients in critical care settings, the work environment of the NNP and implementation of research to establish and disseminate evidence based practice.
BetsyWhite1.pngElizabeth White is a first year pre-doctoral fellow.  She holds a BSN and MSN from the University of Pennsylvania and an MPH in Health Policy and Management from Columbia University.  She is a board-certified adult and geriatric nurse practitioner and her predominant clinical interest is long-term care of the frail medically complex older adult.  Elizabeth currently practices at LIFE, Penn’s Program of All-Inclusive Care for the Elderly site in West Philadelphia, and prior to this, worked in nursing homes in New York City for eight years as an NP with Optum (formerly Evercare), a division of United Healthcare.  Her research interests include nurse retention and the relationship between nurse work environment and quality outcomes in the nursing home setting.
Hillman Scholar
Linda Kang has a BSN with a minor in multicultural/global health care and a BA in Health and Societies with a concentration in Public Health from the University of Pennsylvania. Linda is a Hillman Scholar for Nursing Innovation in the first cohort of the BSN to PhD program. Her research interests are in international health care, inter-professional education and collaboration, nurse work environment and health policy. This past summer Linda traveled home to China to conduct qualitative research on the field exploring managers', nurses' and patients' attitudes towards community health centers.