A new model for nurse practitioner utilization in primary care: Increased efficiency and implications Nan Liu Stacey R. Finkelstein Lusine Poghosyan Background: Nurse practitioners (NPs) play an important role in providing quality primary care. However, little is known about organizational processes that best utilize NPs in care delivery and what kind of resources and support NPs need to deliver quality care within their organizations. In primary care settings, NPs often receive little support from ancillary personnel compared with physicians. Purpose: The aim of this article was to compare the productivity and cost efficiency of NP utilization models implemented in primary care sites with and without medical assistant (MA) support. Methodology/Approach: We develop queueing models for these NP utilization models, of which the parameters are extracted from literature or government reports. Appropriate analyses are conducted to generate formulas and values for the productivity and cost efficiency. Sensitivity analyses are conducted to investigate different scenarios and to verify the robustness of findings. Findings: The productivity and cost efficiency of these models improve significantly if NPs have access to MA support in serving patients. On the basis of the model parameters we use, the average cost of serving a patient can be reduced by 9%Y12% if MAs are hired to support NPs. Such improvements are robust across practice environments with different variability in provider service times. Improving provider service rate is a much more effective strategy to increase productivity compared with reducing the variability in provider service times. Practice Implications: To contain costs and improve the utilization of NPs in primary care settings, MA assistance for NPs is necessary. P olicy makers and many other stakeholders are con- stantly searching for ways to reduce the cost of health care delivery while increasing timely access and providing high-quality patient care. The U.S. health care system does not rank highly among the health care systems of developed countries, mainly because of its high cost and poor outcomes (Murray & Frenk, 2010; Schoen, Osborn, How, Doty, & Peugh, 2009). Although costs are steadily increasing, delays in receiving high-quality care continue to be a challenge in the United States. For exam- ple, 32% of Medicare beneficiaries and 31% of privately in- sured patients had an unwanted delay in obtaining an appointment for routine care in 2008 (Medicare Payment Advisory Commission, 2009). In addition, the average wait time for a new patient to obtain an appointment to see an internist was 31 days in 2008 in Massachusetts (Massachusetts Medical Society, 2008). Finally, a 2009 survey shows that Key words: cost-efficiency, nurse practitioner, primary care, productivity, queueing theory Nan Liu, PhD, is Assistant Professor, Department of Health Policy and Management, Mailman School of Public Health, Columbia University, New York. E-mail: nl2320@columbia.edu. Stacey R. Finkelstein, PhD, is Assistant Professor, Department of Health Policy and Management, Mailman School of Public Health, Columbia University, New York. E-mail: sf2559@columbia.edu. Lusine Poghosyan, PhD, MPH, RN, is Assistant Professor, Columbia University School of Nursing, New York. E-mail: lp2475@columbia.edu. The authors have disclosed that they have no significant relationship with, or financial interest in, any commercial companies pertaining to this article. DOI: 10.1097/HMR.0b013e318276fadf Health Care Manage Rev, 2014, 39(1), 10Y20 Copyright B 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins 10 JanuaryYMarch & 2014 Copyright © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.