Nurse Practitioner Practice: Full Scope, Better Outcomes

Tom G. Bartol, NP

October 08, 2014

Impact of Nurse Practitioners on Health Outcomes of Medicare and Medicaid Patients

Oliver GM, Pennington L, Revelle S, Rantz M
Nurs Outlook. 2014 Aug 1. [Epub ahead of print]

Nurse Practitioner Level of Practice

There is a need to address the high costs and often poor quality of healthcare in the United States. Many studies show that nurse practitioners (NPs) provide safe and high-quality care when compared with other healthcare providers. Yet there are different levels of NP practice in this country as a result of the differences in state licensing laws. Some states have restrictive practices, whereas others allow full scope or independent practice for NPs.

In this study, the researchers analyzed data to determine the impact that level of practice (full, reduced, or restricted) of NPs in the United States has on the outcomes of Medicare and Medicaid patients, focusing on avoidable hospitalizations, readmission rates, nursing home resident hospitalizations, and health outcome rankings.

Full practice was defined as absolute independent practice in which the NP is responsible exclusively to a state board of nursing. Reduced practice was defined as a collaborative practice agreement with a physician specifying the scope of practice allowed. Restricted practices were those that required a physician to oversee all care provided by the NP.

Oliver and colleagues obtained data from the Centers for Medicare and Medicaid Services (CMS) and other organizations that had data ranked by state; health outcomes were then studied. Potentially avoidable hospitalizations for Medicare and Medicaid beneficiaries were reviewed from 2007 to 2009. Thirty-day rates of readmission to hospitals from post-acute rehabilitation were reviewed from 2006 to 2011. Nursing home resident hospitalizations were reviewed from fiscal year 2011. Finally, health outcome rankings by the state were obtained from the United Health Foundation report on America's 2012 health rankings.

Study Findings

Statistically significant improved outcomes were found in all 4 areas in states with full practice (n=17) compared with states without full practice (n=33). Potentially avoidable hospitalizations for Medicare and Medicaid beneficiaries were 100/1000 person-years in the full practice states compared with 146/1000 person-years in the states without full practice. Thirty-day hospital readmissions after discharge from rehabilitation were 10.46 in the full practice group and 11.68 in the states without full practice. Annual hospitalization of nursing home patients averaged 18.1 in full-practice states vs. 25.9 in states without full practice. Overall health outcomes (with lower numbers corresponding to better outcomes) averaged 17 in the full-practice states and 30 in the states without full practice.

When compared individually with either reduced or restricted practice, full-practice states had statistically significantly better outcomes in all 4 areas compared with either of the limited practice states.

The investigators point out that these are associations and that causality cannot be confirmed, but these outcomes should be examined closely and should be an impetus for further changes in public policy to ensure that NPs have full practice across the country.


NP scope of practice varies by state in this country. Each state board of nursing determines how independent or restricted NP practice will be. Politics, rather than logic, often influences this determination. For example, several years ago I practiced as an NP in the state of Missouri. In Missouri, there were nurses, pharmacists, and physicians on the board that licensed NPs. I was required to practice under the supervision of a licensed physician. I could only practice in an office on my own if a physician was available within a 30-mile radius of my location. Prescribing any controlled substance was not permitted.

Later, I moved to the state of Maine. In Maine, I am licensed independently and practice independently, without the requirement of any supervision. Now I am permitted to prescribe schedule II-V controlled substances without supervision. Maine, which had only nurses regulating NPs on its licensing board, doesn't restrict NP practice.

Did my competency or my skills change with the move to Maine? Am I more knowledgeable or able to provide better clinical care in Maine? Absolutely not! I was the same NP I had been in Missouri. The change was in the rules of the state.

The Institute of Medicine issued a report 3 years ago titled, "The Future of Nursing: Leading Change, Advancing Health."[1] A key recommendation in this report was to remove scope-of-practice barriers for advanced practice registered nurses (APRNs). The Federal Trade Commission also raised the question of the legitimacy of barriers to APRN practice in a recent report.[2] They stated that removing barriers that limit full scope of practice for NPs will improve access and quality of healthcare.

This study looks at how full scope of NP practice might improve health outcomes and health status. Comparing outcome data from states that have full scope of practice with those permitting only limited scope of practice, Oliver and colleagues found significantly fewer avoidable hospitalizations, readmissions after discharge from rehabilitation, and nursing home resident hospitalizations. States with full scope of practice also had higher health outcome rankings than states with limited scope of practice for NPs.

Are the barriers to full practice affecting access, cost, and outcomes of care? Although these data show an association or relationship, and not cause and effect, they merit some attention. The barriers to practice that result in reduced or restricted practice of NPs are allegedly to protect the public, yet the research has shown NP care to be equal to that of physicians.[3-5] In some studies, patients preferred care by NPs over physicians.

This study echoes the calls from the Institute of Medicine, the Federal Trade Commission, and numerous publications that support removal of barriers to the full scope of practice for NPs, saying that supervision and collaborative practice add to the burden of providing care without any gains in quality or lowering of the cost of care. Independent practice for NPs has proven to result in safe, high-quality, compassionate, and cost-effective care.



  1. Institute of Medicine. The Future of Nursing: Leading Change, Advancing Health. Washington, DC: National Academies Press; 2011.

  2. The Federal Trade Commission. Policy perspectives: competition and the regulation of advanced practice nurses. March 2014. Accessed September 8, 2014.

  3. Lentz ER, Mundinger MO, Kane RL, Hopkins SC, Lin SX. Primary care outcomes in patients treated by nurse practitioners or physicians: two-year follow up. Med Care Res Rev. 2014;61:332-351.

  4. Newhouse RP, Stanik-Hutt J, White KM, et al. Advanced practice nurse outcomes 1990-2008. Nurs Econ. 2011;29:230-250. Accessed September 30, 2014.

  5. Naylor MD, Kurtzman ET. The role of nurse practitioners in reinventing primary care. Health Aff (Millwood). 2010;29:893-899.