Growing Ranks of Advanced Practice Clinicians



Growing Ranks of Advanced Practice Clinicians

n engl j med 378;25 June 21, 2018

Growing Ranks of Advanced Practice Clinicians

Growing Ranks of Advanced Practice Clinicians — Implications for the Physician Workforce David I. Auerbach, Ph.D., Douglas O. Staiger, Ph.D., and Peter I. Buerhaus, Ph.D., R.N.

Throughout the history of mod-ern American medicine, phy- sicians have made up the vast majority of professionals who di- agnose, treat, and prescribe medi- cation to patients. Although de- mand for medical services has increased markedly over the years (and is projected to grow more rapidly as the population ages), the physician supply has grown relatively slowly. Increased dele- gation of work, new technology, and streamlined care processes can help practices meet patient needs with fewer physicians, but still require an increasing num- ber of health professionals.1

Physician supply is constrained in the short run by long training times and in the longer run by medical school capacity and the number of accredited residency positions. Despite a 16% increase in graduate medical education (GME) slots in recent years, the Association of American Medical Colleges (AAMC) recently project- ed that the supply of physicians will increase by only 0.5% per year between 2016 and 2030.

A growing share of health care services are being provided by ad- vanced practice registered nurses (APRNs), particularly nurse prac- titioners (NPs), who make up the majority of APRNs, and by physi- cian assistants (PAs). NPs and PAs provide care that can overlap with care provided by physicians (both in primary care and increasingly in other specialties), and the AAMC recognizes this overlap in its physician-demand forecasts. The number of NPs and PAs is

growing rapidly, in part because of shorter training times for such providers as compared with phy- sicians and fewer institutional constraints on expanding educa- tional capacity. Residencies aren’t required for APRNs — though organizations are increasingly offering them — and education programs have proliferated: ac- cording to the American Associ- ation of Colleges of Nursing, the number of NP degree programs (master’s or doctorate) grew from 282 to 424 between 2000 and 2016. Baccalaureate-prepared RNs typically require 2 to 3 years of graduate education to become certified NPs. PA programs typi- cally take 2 years and also don’t require residencies. According to the National Center for Education Statistics, the number of PA de- gree programs grew from 135 to 238 between 2000 and 2016.

These dynamics will have last- ing effects on the composition of the health care workforce and on working relationships among health professionals. To take a closer look at these trends, we estimated the number of full-time- equivalent physicians, NPs, and PAs between 2001 and 2016 using data from the U.S. Census Bu- reau’s American Community Sur- vey, which included a roughly 0.4% sample of the U.S. popula- tion between 2001 and 2004 and a 1% sample between 2005 and 2016. Because the Census didn’t identify NPs until 2010, we ob- tained data on NPs from the Na- tional Sample Survey of Regis- tered Nurses from 2000, 2004,

and 2008. Figures were validated using data from health profes- sional associations. The final data set includes 12,887 NPs, 12,801 PAs, and 166,103 physicians.

These data were used to proj- ect the number of NPs, PAs, and physicians through 2030 using methods described in greater de- tail elsewhere.2 Briefly, our model estimates the number of provid- ers of various ages in each year as a function of both workforce- participation patterns associated with age and estimates of differ- ences among birth cohorts in rates of entry into each profession, which ref lect institutional con- straints. Our projections assume that age-related workforce-partici- pation patterns will remain stable after 2016 and that the size of the workforce for birth cohorts that have not yet entered the labor force will resemble that of the five most recent cohorts. In the case of physicians, to better cap- ture the expansion in medical ed- ucation and throughput in recent years, we assume that the size of future cohorts will resemble the size of only the most recent (larg- est) cohort. In our prior work, this model has successfully fore- cast health care workforce trends.2

As shown in the table, between 2001 and 2010, workforce supply increased by roughly 150,000 phy- sicians (an increase of 2.2% per year), 27,000 NPs (an increase of 3.9%), and 44,000 PAs (an increase of 7.9%). Between 2010 and 2016, the combined increase in NPs and PAs (79,000) outpaced the increase in physicians (58,000), although





Growing Ranks of Advanced Practice Clinicians

n engl j med 378;25 June 21, 2018

the NP and PA workforces were roughly one tenth the size of the physician workforce in 2010. Dur- ing this period, growth in the NP supply accelerated to nearly 10% per year, whereas growth in the PA supply slowed to 2.5% and growth in physician supply slowed to 1.1%. The number of NPs and PAs per 100 physicians nearly doubled between 2001 and 2016, from 15.3 to 28.2.

We project that these trends will continue through 2030. The number of full-time-equivalent physicians is expected to continue growing by slightly more than 1% annually, as increased retirement rates are offset by increased en- try, whereas the numbers of NPs and PAs will grow by 6.8% and 4.3% annually, respectively. Rough- ly two thirds (67.3%) of practi- tioners added between 2016 and 2030 will therefore be NPs or PAs, and the combined number of NPs and PAs per 100 physi- cians will nearly double again to 53.9 by 2030. These shifts will probably be even more pro- nounced in primary care, where physician supply has been grow- ing more slowly than in other fields and NPs tend to be more concentrated.

The changing composition of the workforce will have implica- tions for provider teams. Primary care providers, in particular, in- creasingly work in larger groups of professionals with varying back- grounds and types of training. A 2012 national survey of primary care NPs and physicians found that 8 in 10 NPs worked in col- laborative practice arrangements with physicians and 41% of phy- sicians worked with NPs — a percentage that will probably grow over time.3 As more states ex- pand practice authority for NPs, medical practices will have to ad- just. A recent study of working relationships between NPs and physicians on primary care teams in New York and Massachusetts found that physicians, other staff, and patients often confused the roles and skills of various provid- ers and that these misunderstand- ings often led to practices under- mining the productivity and efficiency of NPs.4 Physicians, NPs, and PAs will all need to be trained and prepared for this new reality.

Greater reliance on nonphy- sician clinicians is unlikely to threaten quality of care or increase costs. There is growing evidence

that the primary care provided by NPs and PAs is similar to that provided by physicians, and a re- cent national study of Medicare beneficiaries found that the cost of primary care provided by NPs was significantly lower than the cost of physician-provided care.5

As with other projections, our findings are subject to some de- gree of uncertainty. It is unlike- ly that the physician supply will grow more rapidly than we proj- ect: the AAMC projects even slow- er growth, the number of GME slots is constrained, and even an immediate expansion of medical school capacity and training op- portunities wouldn’t substantial- ly affect the physician supply for many years. Growth in the NP and PA workforces is more un- certain. Although shorter, more flexible training requirements for these providers have facilitated an unprecedented increase in new en- trants, growth rates could fall if demand for nonphysician provid- ers is lower than anticipated and job-market prospects worsen. Major changes are unlikely, how- ever, given the expected increases in demand for care, growing use of team-based and interprofes- sional practice, and the fact that

Provider Group No. of Full-Time Equivalents Average Annual Growth (%)

2001 2010 2016 2030

(projected) 2001–2010 2010–2016 2016–2030 (projected)

Physicians 711,357 862,698 920,397 1,076,360 2.2 1.1 1.1

Nurse practitioners 64,800 91,697 157,025 396,546 3.9 9.4 6.8

Physician assistants 44,282 88,047 102,084 183,991 7.9 2.5 4.3

* Based on data from the American Community Survey (ACS) and the National Sample Survey of Registered Nurses. Estimates for NPs in 2001 are interpolated on the basis of data from the 2000 and 2004 surveys. Full-time equivalents are defined on the basis of reported usual weekly hours worked and a 40-hour workweek for NPs and PAs and a 50-hour workweek for physicians. NPs include a small number of certified nurse midwives who were not separately identified in the ACS because of their small numbers. PAs in the ACS reporting an associate’s degree or less education were excluded. All estimates are based on sample weights provided in each survey.

Historical and Projected Numbers of Physicians, Nurse Practitioners, and Physician Assistants.*





Growing Ranks of Advanced Practice Clinicians

n engl j med 378;25 June 21, 2018

NPs disproportionately serve ru- ral and underserved populations, whose needs would otherwise go unmet.

Despite these uncertainties, it is clear that patients will continue to encounter more NPs and PAs when they seek care. The shifting composition of the health care workforce will present both chal- lenges and opportunities for med- ical practices as they redesign care pathways to accommodate new payment methods, new in- centives regarding quality of care,

and the demands of an aging population.

Disclosure forms provided by the authors are available at

From the Center for Interdisciplinary Health Workforce Studies, College of Nursing, Montana State University, Bozeman (D.I.A., P.I.B.); the Department of Economics, Dart- mouth College, Hanover, NH (D.O.S.); and the National Bureau of Economic Research, Cambridge, MA (D.O.S.).

1. Bodenheimer TS, Smith MD. Primary care: proposed solutions to the physician shortage without training more physicians. Health Aff (Millwood) 2013; 32: 1881-6. 2. Staiger DO, Auerbach DI, Buerhaus PI.

Comparison of physician workforce esti- mates and supply projections. JAMA 2009; 302: 1674-80. 3. Donelan K, DesRoches CM, Dittus RS, Buerhaus P. Perspectives of physicians and nurse practitioners on primary care practice. N Engl J Med 2013; 368: 1898-906. 4. Poghosyan L, Norful AA, Martsolf GR. Primary care nurse practitioner practice characteristics: barriers and opportunities for interprofessional teamwork. J Ambul Care Manage 2017; 40: 77-86. 5. Perloff J, DesRoches CM, Buerhaus P. Comparing the cost of care provided to Medicare beneficiaries assigned to primary care nurse practitioners and physicians. Health Serv Res 2016; 51: 1407-23.

DOI: 10.1056/NEJMp1801869 Copyright © 2018 Massachusetts Medical Society.Growing Ranks of Advanced Practice Clinicians

The Graduate Nurse Education Demonstration

The Graduate Nurse Education Demonstration — Implications for Medicare Policy Linda H. Aiken, Ph.D., R.N., Joshua Dahlerbruch, B.S.N., Barbara Todd, D.N.P., and Ge Bai, Ph.D., C.P.A.

Despite decades of public and private investment, the United States continues to have a short- age of primary care capacity. Only 2699 graduating U.S. medi- cal students — about 17% of graduates from allopathic and osteopathic schools — matched with primary care residencies in 2016.1 Studies show that nurse practitioners (NPs) provide high- quality primary care that is satis- factory to patients, improves ac- cess to care in underserved areas, and may reduce costs of care. But although Medicare spends more than $15 billion annually on graduate medical education (GME),2 including training for pri- mary care physicians, it spends very little on clinical training for NPs.

Medicare has contributed to the cost of training nurses since its inception, but NP programs didn’t exist when Medicare was enacted and such funding streams

were established. Modernizing Medicare’s payment policies for nurse training is highly relevant, given the recent success of the Graduate Nurse Education (GNE) Demonstration.3 The $200 million, five-site Centers for Medicare and Medicaid Services (CMS) demon- stration authorized under the Affordable Care Act showed that offering payments to Medicare providers enabled more of them to participate in clinical precept- ing of advanced practice regis- tered nurses (APRNs) and result- ed in a substantial increase in the number of new APRN gradu- ates. More than 60% of training took place in community-based settings, and primary care NPs accounted for most of the growth in the number of new graduates.

The GNE Demonstration doc- umented the success of a new model of organizing and paying for graduate nurse education in- volving consortia of hospitals

and health systems, community partners, and university nursing schools managed by a single Medicare hospital hub. Such con- sortia were originally proposed in 1997 by the Institute of Medi- cine (now the National Academy of Medicine) as a strategy for in- creasing community-based train- ing for physicians, but were not implemented until the GNE Dem- onstration. Of the five demonstra- tion networks, three were state or regional consortia covering greater Philadelphia, the Texas Gulf Coast, and Arizona. In great- er Philadelphia — the largest con- sortium — the Hospital of the University of Pennsylvania served as the designated hub for a re- gional network that included all health systems and hospitals in the area, more than 600 com- munity-based providers, and all 9 local university nursing schools involved in training APRNs. This model has many advantages. For



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