Knowing Your Limits: A Qualitative Study of Physician and Nurse Practitioner Perspectives on NP Independence in Primary Care
J Gen Intern Med
Knowing Your Limits: A Qualitative Study of Physician and Nurse Practitioner Perspectives on NP Independence in Primary Care
Elena Kraus 1
James M. DuBois
0 Division of General Medical Sciences, Washington University School of Medicine , St. Louis, MO , USA
1 Department of Obstetrics, Gynecology and Women's Health, Saint Louis University School of Medicine , St. Louis, MO , USA
BACKGROUND: The shortage of primary care providers and the provisions of the Affordable Care Act (ACA) have spurred discussion about expanding the number, scope of practice (SOP), and independence of primary care nurse practitioners (NPs). Such discussions in the media and among professional organizations may insinuate that changes to the laws governing NP practice will engender acrimony between practicing physicians and NPs. However, we lack empirical, descriptive data on how practicing professionals view NP independence in primary care. OBJECTIVE: The aim of the present study was to explore and describe the attitudes about NP independence among physicians and NPs working in primary care. DESIGN: A qualitative study based on the principles of grounded theory. PARTICIPANTS: Thirty primary care professionals in Missouri, USA, including 15 primary care physicians and 15 primary care NPs. APPROACH: Semi-structured, in-depth interviews, with data analysis guided by grounded theory. KEY RESULTS: Participants had perspectives that were not well represented by professional organizations or the media. Physicians were supportive of a wide variety of NP roles and comfortable with high levels of NP independence and autonomy. Physicians and NPs described prerequisites to NP independence that were complementary. Physicians generally believed that NPs needed some association with physicians for patient safety, and NPs preferred having a physician readily accessible as needed. The theme Bknowing your limits^ was important to both NPs and physicians regarding NP independence, and has not been described previously in the literature. CONCLUSIONS: NP and physician views about NP practice in primary care are not as divergent as their representative professional organizations and the news media would suggest. The significant agreement among NPs and physicians, and some of the nuances of their perspectives, supports recommendations that may reduce the perceived acrimony surrounding discussions of NP independent practice in primary care.
qualitative research; advanced practice nursing; primary care; professional responsibilities; interprofessional
Primary care is the principle form of care fundamental to
effective and affordable health care, provided by clinicians
who are able to address a large majority of health needs,
develop a sustained partnership with patients, and practice in
the context of family and community [
]. Increased access to
primary care is associated with lower mortality rates and lower
costs due to better preventive care, lower hospitalization rates,
and the reduction of unnecessary specialty care [
Nevertheless, data indicate a growing shortage of primary care
providers , which has provided the impetus for the current
debate about expanding the number, scope of practice (SOP),
and independence of primary care nurse practitioners (NPs).
While physician interest in primary care has plummeted,
NP numbers have risen, from 30,000 in 1990 to 140,000 in
]. The majority (89 %) of NPs have a primary care
focus, specializing in family (49.2 %), adult (17.9 %), and
pediatric care (9.4 %), women’s health (9.1 %), and
gerontology (3 %) . The NP workforce can be expanded with less
training time than that for physicians [
Some data indicate that NPs can provide about 90 % of
primary care services commonly provided by physicians, with
at least comparable outcomes and at lower cost [
]. NPs have
similar types of malpractice claims to those of physicians, but
lower malpractice rates, and no data suggest that increased use
of NPs increases physician liability [
]. Research also
indicates that NPs score consistently higher in patient satisfaction,
patient compliance, health promotion, and disease prevention
]. Many physicians agree that NPs are a great addition to
a clinic, because they Bcan pay for themselves^  and reduce
physician workload [
Accordingly, the 2010 Institute of Medicine (IOM)
report on BThe Future of Nursing^ supported greater
roles for NPs in primary care and equal reimbursement
for the same services provided by physicians [
the Affordable Care Act (ACA) designated significant
funds for NP training and education, NP-managed health
clinics, and loan programs for nurses to pursue
advanced nursing degrees [
Nevertheless, policies aimed at increasing the number,
SOP, and independence of NPs have been met with
significant debate [
]. Several national medical organizations
explicitly oppose many of the changes that NPs have worked
toward and the recommendations of the IOM report. These
include the American Medical Association (AMA) [
American Association of Family Practitioners (AAFP) [
The Physicians Foundation [
], The Council of Medical
Specialty Societies (CMSS) [
], and the American Academy
of Pediatrics (AAP) [
]. Their arguments focus on the lower
number of years of education and training that NPs have
compared with physicians, which they argue may put patients
at risk and create a two-tiered system of medical care.
Surprisingly few studies have examined the perspectives of
primary care physicians and NPs toward each other [
Descriptive interview data are sparse, and what has been
published is outdated or international in nature [
research on perceptions among these professionals is the result
of surveys and questionnaires, which may yield responses that
are difficult to contextualize and interpret [
]. The few
studies that have been conducted have produced ambiguous
results, with a majority of physicians identifying advantages to
working with NPs  and a majority of physicians and NPs
reporting good relationships [
], while pluralities express
deep concerns about NP SOP, independence, or relationships.
However, none of these studies provided data on the deeper
reasons for these views or explained their ambiguous findings.
This exploratory study sought to provide a rich descriptive
understanding of how doctors and NPs feel about NP practice
in primary care, particularly their independent practice, and
Qualitative methods were used to gather and analyze data.
Indepth interviews followed the general guidelines provided by
Corbin and Strauss for descriptive exploratory studies [
Literature review informed the development of the interview
guide, while sampling and data analysis where guided by the
principles of grounded theory [
]. The interview guide was
meant to support a hybrid approach to data gathering and
analysis, combining conventional content analysis, which is
largely open-ended and inductive, and directed content
analysis, which is largely deductive and driven by literature reviews
and pre-existing theory [
]. This qualitative approach was
appropriate given that the aim was to explore the experiences
of NPs and physicians working with each other. The study was
conducted toward completion of the first author’s MD/PhD
program, with the second author, a PhD researcher in ethics
and social science, serving as mentor. The first author
conducted all interviews; the two authors collaborated in the
development of the interview guide, codebook, and data
analysis. The authors used a third-party transcription service.
We recruited 15 physicians and 15 NPs working in academic
and private primary care practices. Purposive sampling was
used to select participants on the basis of their credentials and
specific experiences as medical professionals [
and primary care offices were called and emailed to invite
participation from selected professionals, and others were
gained by snowballing. Participation was incentivized with a
$25 gift card to a local bakery. A sample size of 15 was
tentatively established as adequate to achieve data saturation.
Research has indicated that saturation in qualitative interview
studies often occurs within the first 12 interviews [
Data were gathered in person in St. Louis County, Missouri, at
locations convenient for participants. The location is relevant
to interpreting the experiences of participants, as Missouri
state laws governing NP practice are among the most
restrictive in the US [
]. The study protocol was approved by the
university’s institutional review board (#20794). The study
posed minimal risk to participants, and all participants
provided informed consent.
Data were collected through semi-structured, in-depth
interviews performed by the primary researcher and through a
questionnaire on participant demographics. Interviews were
audio recorded and transcribed by a third-party transcription
service. Reflexivity in data collection and analysis was
practiced, while still working to maintain some degree of
detachment and objectivity. Observational notes were written
immediately following each interview [
]. This process was
formalized by the use of journals in which interviewers recorded
their responses to nine post-interview questions that examined
their feelings, dynamics, and interactions with the participant,
mood, and notable characteristics of the practice and work
environment. Fifteen interview questions were developed,
following significant review of the literature, to ensure
relevance and to build on prior data. The interview began with a
broad, open-ended question to enable identification of
spontaneously generated theme, followed by questions about more
specific issues in primary care, including NP roles, SOP, NP
impact on care quality and the larger primary care system, and
NP relationships with physicians (see Online Appendix A).
Follow-up questions were used to define terms and to clarify
Data analysis was ongoing; interviews were transcribed, read,
and analyzed as they were being conducted. The Text Analysis
Markup System (TAMS) was used to search, code, and
organize transcript data. Analysis was driven by the search for
concepts that could be coded, compared, and related to each
other [ ]. Constant comparison was used to develop more
valid and specific codes and to develop themes and
interpretations that explained the perceptions expressed. Attention
was paid to significant statements that supported theme
development. Spontaneous themes, that is, themes that surfaced in
response to the opening question or without clear association
with the more specific questions, were noted and developed
into their own set of themes. To improve the reliability of the
codes, the second author reviewed the developing code sheet
at multiple points in the analysis process and read several
entire transcripts to evaluate and challenge the developing
The data in this paper were gathered within interviews
addressing an array of topics too broad to present in one paper.
Here we focus on responses to questions 1–8 of our interview
guide, which center on the quality of care provided by NPs,
NP independence, and NP SOP (see Online Appendix A). The
data presented were selected because of their significant
addition to the literature on these issues; individual quotes were
selected that best represented themes.
Participants represented a variety of ages, specialties, and
backgrounds. The majority of physicians were women
(66.7 %), were white (93.3 %), and practiced in academic
group practices (66.7 %) in an urban environment (93.3 %).
All but two collaborated with NPs regularly, and 12 were
currently in a collaborative practice agreement (CPA) with
an NP. All NPs interviewed were women, 93.3 % were white,
and 66.7 % practiced in an urban environment. Practice
settings varied among NP participants, with four in federally
qualified health centers (FQHC), four in private group
practices, five in academic practices, and two in retail health care
clinics. Physicians spanned a wide age range, with four
between 20 and 39, six between 40 and 49, and five between 50
and 69. NP interviewees similarly represented all ages, with
eight between 50 and 69, and seven between the ages of 20
and 49. Most NPs in higher age ranges had been RNs for a
significantly longer period before continuing their nursing
education. The youngest participants had less than 5 years of
experience as RNs before receiving NP training. Two
interviewees had PhDs, two had DNPs, and two others were
enrolled in DNP programs; all others held a master’s degree
or a graduate-level certificate.
All interviewed NPs had active collaborative practice
agreements with one or more physicians, according to Missouri law.
Participants came from a broad range of professional
experiences, including all identified primary care specialties (internal
medicine, family medicine, women’s health, pediatrics, and
geriatrics). Physician interviews averaged 47 min, and NP
interview length averaged 56 min.
Overall, NPs and physicians had surprisingly similar and
complementary views on many of the issues considered
during interviews. In contrast to the public discourse on
issues relating to NPs practicing in primary care,
participant responses were essentially absent of any tone of
defensiveness or conflict. NPs never cited physicians as
impediments to their professional goals or to treating
patients, and physicians had significant respect for NPs
and evaluated them and their skills with patients
favorably. Neither physicians nor NPs cited significant
empirical data to support their views, even studies or
specific data on the comparative effectiveness of
physicians and NPs. Above all, participants cited their own
experiences with coworkers as support for their
perspectives, illustrating the power of personal experience in
shaping these professionals’ views of one another.
NPs Provide Quality Care
From the initial open-ended question and throughout the
interview, physicians consistently indicated that NPs were great
for primary care. Specific qualities that were highlighted
included NP adaptability, their ability to provide routine primary
care with ease, and the benefits of their unique nursing
approach to patient care.
BI think they’re very—especially in primary care, for the
majority of the population without special needs, I think
nurse practitioners are perfect for that.^ (P3Q2)
BSo to maintain a daily service and basically to keep
the lights on in our practice, it’s very useful to have
nurse practitioners to see patients with us…it’s great.^
NPs, consistent with the views of their representative
organizations, felt their skills were an excellent fit for primary care,
including improving patient access to primary care, their
attention to social issues and education, and the benefits of their
BI think that patients are overall really satisfied with our
care and what we provide to them, and I think it
improves access for a lot of people, because there’s a
lack of providers in primary care.^ (NP3Q1)
BI think nurse practitioners do an awesome job of
providing primary care to all those patient groups,
adult, family, women, because I believe that nurse
practitioners speak at the level of the patient.^
In contrast to what one may take away from the more public
debate on NP independence, physician participants were
supportive and comfortable with high levels of NP
independence and autonomy.
B[T]he nurse practitioners we have currently, I feel, are
very sharp and well trained, and so if the average nurse
practitioner is like them, I would feel very comfortable
knowing that they were practicing independently…I
think for primary care I could see them being given
independent privileges.^ (P12Q2)
In turn, NP participants described a clear sense of
independence they felt in practice, while highly valuing having
physicians close by to consult as needed.
BAt least in primary care, I think we pretty much have
an ideal situation. I think all of our physicians, I can’t
think of any of them really that I don’t like to work
with. They give us our independence, which is good.
So I think ideally, you know, we see the patient, we
pretty much are allowed to treat as we feel we should…
They come when we need them and they leave us alone
when we don’t need them, but they’re always there for
consult, but they’re not hovering. They show an
interest in the patients, but they’re not constantly worried
that you’re going to be doing something wrong. So just
to have the independence and not have them hovering
over you is probably a big thing.^ (NP1Q10)
BI can be and am already the sole provider for patients,
again, with the caveat that there is attending physicians
available if the care gets beyond my scope of practice.^
For both groups of professionals, NP independent practice
carried with it certain prerequisites. For physicians, these
caveats included knowing your limits, experience, and training.
BI prefer to work with people who are very independent
but know when to ask questions.^ (P13Q2)
BIt’s definitely appropriate that they can see patients on
their own, with somebody that is trained, that has
clinical experience.^ (P3Q2)
For NPs, necessary skills included experience, and a
physician connection. Most expressed a preference for having a
physician quickly accessible, as needed, for questions and
BI think it depends on the comfort level of the nurse
practitioners and her level of expertise and experience.
I think as nurse practitioners practice longer, they end
up being more independent…you also learn what your
level of comfort is and when it’s time to refer out or to
get consult…so I think it’s something that should be
weighed individually by the level of expertise.^
BI think having the collaborative practice agreement
with a physician and the group is very important…I
think it’s important because we didn’t have the
schooling of a doctor…but I am capable to be your provider
and to provide that treatment and the diagnosis and the
care and all of those things that come with it. But I do
think that a level of supervision is important.^
Similar to the profession’s public commentary, most
physician participants insisted on some degree of supervision by an
accessible physician to ensure patient safety, given perceived
gaps in NP training.
BI think there should be some oversight so that the
quality is maintained. I think there needs to be some,
as we have now, a scope of practice of what nurse
practitioners are trained to do and the scope of their
practice. And also that that can be modified over time
as new information comes out or new aspects of the
care that they’re qualified to do. I think with that
overall supervision for quality, making sure people
are working within their scope of care, it’s a very good
Importantly, the way participants defined supervision
was far less invasive than the way it is depicted
publicly. Both groups of professionals rejected the idea that
the physician must be a hovering presence to ensure
good care quality. When one physician was asked to
clarify her meaning of Bdirect supervision,^ she replied
that it simply meant that the two professionals were Bin
the same office.^ (P6Q2). Physicians routinely used the
idea of supervision and collaboration interchangeably to
describe this preferred arrangement of the different
providers working in the same practice. Collaboration was
a means of supervision.
Physicians also indicated that the specific practice environment
had an effect on the appropriate degree of independence. In their
minds, the needs of the community could necessitate an NP
working independently, but they should still have an available
physician to consult with in case they needed it, albeit less directly.
BI think it sort of depends, and I think there’s also
needs, you have to balance the needs of the
BFor some people, that availability may be by phone,
depending on the time and things like that, which I
think is fine too. I just think having that availability…
we have nurse practitioners who have their own clinic
and they just can call their collaborating physician as
NPs similarly indicated that the environment in which they
practiced had an effect on the level of independence
appropriate for ensuring patient safety and quality care, while
still providing access.
BI think that they should be able to be independent, like
in a rural setting where there aren’t any physicians.^
BI’m very big on access, because there’s a lot of
people who don’t have access to health care
services, and I think allowing certain practitioners
to practice independently is good in terms of
getting patients access. (NP6Q3)
Knowing Your Limits
The theme of Bknowing your limits^ has not been
previously described in the literature on these
professionals’ perspectives, yet came up repeatedly from all
participants throughout interviews. It was a key theme
in responses to questions 1, 2, 4, 5, and 10. Both
groups of professionals mentioned this theme during
their discussions of independent practice.
Physicians saw it as a required skill in NPs crucial to their
ability to provide quality care.
BThey have to know their own boundaries. Okay,
if they’re really good at what they do, they know
when they’ve come across something that they
shouldn’t be dealing with and they should refer.
The really good ones know that.^ (P4Q1)
Knowing your limits was described as practically a
moral imperative for NPs, as it represented a concern
for the good of patients as well as one’s professional
credibility. They also considered it a foundational
element of quality care and essential for maintaining
physicians’ trust in the collaboration. NPs insisted that they
knew their limits, and would always stay within them to
ensure safe and quality patient care.
BI’m very attuned to what my limits are, and I do
not ever encroach on them, because that is the
basis of nurse practitioner and physician
collaboration is that my physicians know that I’m gonna
do what I’m comfortable with, and I will get
them when I know I’ve reached that limit.^
Physicians agreed that NPs knew their limits and asked
questions appropriately within an otherwise independent
BThey are—at least in my experience, all the nurse
practitioners that I’ve worked with have been really
good about asking for help when they need it, when
they’re not sure or things like that, so I think that works
Both professionals agreed that the situation was no different
from that with primary care physicians, who need to decide
when to refer a patient to a specialist.
BI was no different when I was in private practice. I
handled things, and then when I had questions that
were beyond my expertise or knowledge, I called
specialists, so I would see nurse practitioners act in that
same way.^ (P5Q2)
Notably, an absence of this trait was generally attributed to
personality rather than degrees held, level of training, or
BI think the only concern is if there’s someone who
thinks they know more than they do, and they won’t go
for help or consult with a physician. The nurse
practitioners I have worked with, I’ve never really seen that
to be a problem.^ (NP1Q1)
BAnd also the person. I’m sure there are also physicians
out there who are very cavalier about what they think
they know. So certainly there can be nurse practitioners
who are the same way, who think they know more than
they know or are overconfident. That’s not unique to
… any one profession.^ (P8Q4)
Barriers to Independence
NP participants cited arbitrary or burdensome laws as barriers
to their independence, and not physicians. They had many
examples of practice restrictions based on laws that did not
seem reasonable and did not optimize their ability to provide
the care they saw as part of their SOP.
BAnd then the prescriptive authority. So I can kill
somebody with insulin, but I can’t write for them to
have Adderall so they can study better in school? It
makes no sense… my patients sit in the waiting room
and they wait for my doc to get done seeing those
patients to where they can bring their script to them
and have them sign it. It’s crazy, absolutely crazy.^
Their focus on NP independence was very patient-oriented,
and not self-promoting or defiant. They were concerned about
getting quality care to patients. Physicians similarly referenced
arbitrary laws and practice restrictions that seemed
unreasonable for safe and efficient care, albeit less frequently than NPs.
They voiced support for their NP colleagues in such positions
when a relationship of trust was established.
This study elicited findings that aid in a deeper understanding
of how these professionals think about NP independent
practice in primary care, offering highly descriptive qualitative
data unique in this realm. While our study does not have direct
implications for policy development, which can be politically
highly charged, we believe that the findings can inform the
way that dialogue about policy is structured.
Improving the NP–Physician Discussion
In the public sphere, terms such as Bequal,^ Bsubstitute,^
Bindependence,^ and Bdirect supervision^ are used to frame
debates in ways that can polarize [
]. Such language
was rarely present in participant responses, and when it was,
the meaning was never polarizing. When physicians were
asked to clarify words like Bdirect supervision,^ for example,
it was clear that their concept agreed significantly with NPs’
understanding, and its meaning was conducive to productive
discussion. Physician and NP representative organizations
might do well to describe their positions carefully using
specific and patient-centered terms.
NP Independent Practice
Instead of framing the debate surrounding NP independent
practice in terms of what they are and are not trained to do, or
how the two measure up in comparisons, the conversation
could be improved by focusing on whether these professionals
will limit their practice appropriately based on their training.
Based on the results of this study, both physicians and NPs
believe this is a valuable skill, believe that NPs generally have
this skill, and indicate that a lack of this skill depends more on
one’s personality than on experience or training. Just as all
primary care physicians are trusted to know when to refer to a
specialist, both physicians and NPs believed that NPs could be
trusted to know when to seek consultation from, or refer to, a
physician colleague. The operative notion of physician
oversight was not that of an attending with a new intern, but
availability and consultation as needed, and it was welcomed
by both groups of professionals.
Small-sample, qualitative studies are useful for developing
theory, describing the relationship between complex variables,
and identifying questions that deserve further investigation,
but they are limited in their generalizability. The
generalizability of this study was further limited by its focus on primary
care, the strong representation of individuals working in
academic settings, and the fact that all interviews were conducted
in one state, while state laws pertaining to NP independence
and SOP vary widely across states.
It would be informative to conduct a generalizable, nationwide
survey of primary care physicians and NPs on the issues
addressed in our study, to inform the efforts of professional
organizations, educational programs, and legislatures on
matters such as SOP and independence. We believe that this
qualitative study might inform the way that survey items
should be phrased, and what kinds of questions should be
Acknowledgments: The authors disclose receipt of the following
financial support for the research, authorship, and/or publication of
this article: awards to the first author from the university where the
research was conducted, and support to the second author from the
National Center for Clinical and Translational Science.
Corresponding Author: Elena Kraus, MD, PhD; Department of
Obstetrics, Gynecology and Women’s HealthSaint Louis University
S c h o o l o f M e d i c i n e , S t . L o u i s , M O 6 3 1 1 7 , U S A
Compliance with Ethical Standards:
Conflict of Interest: The authors declare no conflicts of interest.
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