NSG 6006 Chapter 2 Conceptualizations of Advanced Practice Nursing (SUMMARY) | South University

Chapter 2 Conceptualizations of Advanced Practice Nursing Judith A. Spross Why are conceptualizations of advanced practice nursing important for students and practicing advanced practice nurses (APN s) to understand? The content may seem dry to students, who are otherwise excited about learning new ways of caring for individuals, through their APN education. Concepts, models, and theories seem remote from the real work of eliciting histories, performing physicals, planning treatment, evaluating outcomes, and otherwise helping patients and families improve their health, cope with illnesses, and die with dignity. Whether one does so consciously, all these advanced practice activities are guided by some model or framework. Novices may rely more frequently on rules and guidelines to accomplish their work. Expert APNs may not consult rules and guidelines for common problems, but can improvise new ways of thinking (models) when faced with novel situations. Regardless of years of experience, APNs rely on common processes and language in their communications with colleagues about patient care and recognize when they must explain a clinical situation to someone unfamiliar with the patient. Similarly, it is important for the nursing profession and for individual APNs to understand the language of advanced practice nursing to communicate with each other, clients, and stakeholders. Currently, converging forces in the United States are moving rapidly, requiring the profession to advance a common understanding of advanced practice nursing, which is likely to inform future conceptualizations of advanced practice nursing. The development of a common language and conceptual framework for communication and for guiding and evaluating practice, education, policy, research, and theory is fundamental to sound progress in any practice discipline. Given the evolving changes in the U.S. health care system, such a foundation is particularly crucial at this stage in the development of advanced practice nursing. Since the last edition, a professional consensus on advanced practice nursing regulation has been reached in the United States—the Consensus Model for APRN Regulation (2008) and is being implemented. In addition, the Institute of Medicine [IOM] (2011) has called for integrating advanced practice nursing more completely into the U.S. health care delivery system. Other forces driving a common understanding of advanced practice nursing are the expansion of programs offering the Doctorate of Nursing Practice (DNP), the Patient Protection and Affordable Care Act (PPACA, 2010), accountable care organizations, and the promulgation of interprofessional competencies (Canadian Interprofessional Health Collaborative [CIHC], 2010; Health Professions Networks, Nursing and Midwifery, & Human Resources for Health, 2010; Interprofessional Education Collaborative [IPEC] Expert Panel, 2011) and education (see Chapters 12 and 22). Understanding what advanced practice nursing is, what APNs do, similarities and differences among APNs, and how APNs contribute to affordable, accessible, and effective care is central to the redesign of U.S. health care. It is important for readers to understand that because of the dynamic and evolving nature of health care reform and nursing organizations' activities in this arena, nationally and globally, the content in this chapter is changing quickly. Readers are encouraged to consult the websites cited in this chapter for up to date information. Internationally, there have been efforts to clarify, establish, and/or regulate advanced practice roles within the nursing profession in other countries (e.g., Canadian Nurses Association [CNA] 2007, 2008, 2009a, b; International Council of Nurses [ICN] (2009). In countries in which APN roles exist, in addition to studies of the distinctions among roles (Gardner, Chang, & Duffield, 2007; Gardner, Gardner, Middleton, et al., 2010), efforts are underway to establish educational programs (Wong, Peng, Kan, et al., 2009) or develop frameworks that clarify education, scope of practice, registration and licensing, and/or credentialing that are country-specific (e.g., Fagerström, 2009). Statements by national organizations such as the CNA and ICN and articles on conceptualizations of advanced practice nursing proposed by authors from other countries (e.g., Ball & Cox, 2004; CNA, 2007, 2008, 2009a, b; DiCenso, Martin-Misener, Bryant-Lukosius, et al., 2010; Gardner, Chang, & Duffield, 2007; Gardner et al., 2010; Mantzoukas & Watkinson, 2007; McMurray, 2011; Pringle, 2010) have been reviewed. Although contextual factors may differ from those in the United States, there are global opportunities for clarifying and advancing advanced practice nursing and these should be specific to a country's culture, health system, professional standards, and regulatory requirements. Content from articles about advanced practice in other countries is used to present models or illuminate certain conceptual issues; they also inform the discussion of recommendations and future directions. For a more complete discussion of global perspectives on advanced practice nursing, see Chapter 6. In reviewing the literature for this edition, searches were conducted using the terms advanced practice nursing, model, or theory, and the four APN roles. In addition, a search was done of the authors of models cited in the prior edition. Few new curricular models were identified (Fagerström, 2009; Perraud, Delaney, Carlson-Sabelli, et al., 2006; Wong et al., 2009), but several types of articles related to model development, model testing, and models used in advanced practice nursing were identified. These models may be characterized as follows: • •Curriculum models (e.g., Fagerström, 2009; Perraud et al., 2006; Wong et al., 2009) • •Administrative or organizational models (e.g., Ackerman, Mick, & Witzel, 2010; Scarpa & Connelly, 2011; Skalla & Caron, 2008) • •Models that differentiate among advanced practice roles (e.g., Gardner, Chang, & Duffield, 2007) • •Models of the nature of advanced practice nursing (e.g., Ball & Cox, 2003; Brown, 1998; Hamric, 1996, 2009, and see Chapter 3; Mantzoukas & Watkinson, 2007; Styles & Lewis, 2000) • •Models that differentiate between basic and advanced practice nursing (e.g., Calkin, 1984; Oberle & Allen, 2001) • •Models of role development of APNs (see Chapter 4) • •Models of APN regulation and credentialing (e.g., the APRN [Advanced Practice Registered Nurse] Consensus Model, 2008; CNA, 2007, 2008, 2009a, b; Stanley, Werner, & Apple, 2009; Styles, 1998); • •Models of interdisciplinary practice (Dunphy & Winland-Brown, 1998; Dunphy, Winland-Brown, Porter, Thomas, & Gallagher, 2011); • •Models that APNs would find useful include the following: o ○Application or testing of grand and middle-range theories to APN practice (e.g., Musker, 2011; Newcomb, 2010); o ○Models of role implementation (Ball & Cox, 2004; Bryant- Lukosius, DiCenso, Browne, & Pinelli, 2004) and APN care delivery (Mahler, 2010; McAiney, Haughton, Jennings, et al., 2008; Dunphy & Winland-Brown, 1998; Dunphy, Winland-Brown, Porter, Thomas, & Gallagher, 2011; Curley, 1998; American Association of Critical Care Nurses, 2012) • •Models to evaluate outcomes of advanced nursing practice (see Chapters 23 and 24). In addition, professional organizations with interests in licensing, accreditation, certification, and educational (LACE) issues regarding APNs can be viewed as operating from some conceptualization of advanced practice nursing, whether implicit or explicit. In this chapter, the following types of models will be discussed: those promulgated by APN stakeholder organizations, models that describe the nature of advanced practice and/or differentiate between advanced and basic practice, and selected models that APNs may find useful in practice. In previous editions, problems associated with lack of a unified definition of advanced practice and imperatives for undertaking this important work were identified. When practicable, consensus on advanced practice nursing models should be beneficial for patients, society, and the profession. Although the APRN Consensus Model (2008) has brought needed conceptual clarity to regulation of advanced practice nursing in the United States, there is still work to be done with regard to other aspects of conceptualizing advanced practice nursing, such as APN competencies, differentiating basic and advanced nursing practice, and differentiating the advanced practice of nursing from the practices of other disciplines. This work has become more urgent given the impacts of other U.S. initiatives that are unfolding. I have reviewed published documents from national professional organizations and the literature and focused selectively on models of APN practice. This review is not exhaustive. For example, in limiting the scope of this chapter, statements on advanced practice nursing by specialty organizations have not been examined. Thus, the purposes of this chapter are as follows: • 1.Lay the foundation for thinking about the concepts underlying advanced practice nursing by describing the nature, purposes, and components of conceptual models. • 2.Identify conceptual challenges in defining and operationalizing advanced practice nursing. • 3.Describe selected conceptualizations of advanced practice nursing. • 4.Make recommendations for assessing existing models and developing, implementing, and evaluating conceptual frameworks for advanced practice. • 5.Outline future directions for conceptual work on advanced practice nursing. Readers are invited to debate and enlarge on the models, issues, and thinking put forward in this chapter. Nature, Purposes, and Components of Conceptual Models A conceptual model is one part of the structure, or holarchy, of nursing knowledge. This structure consists of metaparadigms (most abstract), philosophies, conceptual models, theories, and empirical indicators (most concrete; Fawcett, 2005). Traditionally, key concepts in the metaparadigm of nursing, which nursing theories are expected to address in their conceptual underpinnings, are humans, the environment, health, and nursing (Fawcett, 2005). Although some theorists have proposed additional or expanded concepts, Fawcett's ideas inform this discussion. At this stage of the evolution, conceptual models of advanced practice nursing remain an appropriate focus. • •What is a conceptual model? • •What purposes does it serve? • •What are its components? A number of answers to these questions are in the nursing literature. Fawcett (2005) has identified a conceptual model as “a set of relatively abstract and general concepts that address the phenomena of central interest to a discipline, the propositions that broadly describe these concepts, and the propositions that state relatively abstract and general relations between two or more of the concepts” (p. 16). Fawcett (2005) also noted that a conceptual model is “a distinctive frame of reference…that tells [adherents] how to observe and interpret the phenomenon of interest to the discipline” and “provide alternative ways to view the subject matter of the discipline; there is no ‘best’ way.” Although there is no best way to view a phenomenon, evolving a more uniform and explicit conceptual model of advanced practice nursing is likely to benefit patients, nurses, and other stakeholders (IOM, 2011) and have practical benefits. It can facilitate communication, reduce conflict, ensure consistency of advanced practice nursing, when relevant and appropriate, across APN roles, and offer a “systematic approach to nursing research, education, administration, and practice” (Fawcett, 2005). Thus, conceptual models serve many purposes. Models may help APNs articulate professional role identity and function, serving as a framework for organizing beliefs and knowledge about their professional roles and competencies, providing a basis for further development of knowledge. In clinical practice, APNs use conceptual models in the delivery of their holistic, comprehensive, and collaborative care (e.g., Carron & Cumbie, 2011; Dunphy & Winland-Brown, 1998; Dunphy et al., 2011; Musker, 2011). Models may also be used to differentiate among levels of nursing practice—for example, between staff nursing and advanced practice nursing (Calkin, 1984; ANA, 2010b). In research and other scholarly activities, investigators use conceptual models to guide research and theory development. An investigator could decide to focus on the study of one concept or examine relationships among select concepts to elucidate testable theories. For example, research by Fenton (1985)and Brykczynski (1989) has elucidated new domains of practice for clinical nurse specialists (CNSs) and nurse practitioners (NPs), respectively. In education, faculty use conceptual models to plan curricula, identify important concepts and the relationships among them, and make choices about course content and clinical experiences for preparing APNs (Perraud et al. 2006; Wong et al., 2009). Fawcett and colleagues (Fawcett, Newman, & McAllister, 2004; Fawcett & Graham, 2005) have raised additional conceptual questions about advanced practice: • •What do APNs do that makes their practice “advanced?” • •To what extent does incorporating activities traditionally done by physicians qualify nursing practice as “advanced?” • •Are there nursing activities that are also advanced? Because direct clinical practice is viewed as the central APN competency, one could also ask: “What does the term clinical mean? Does it refer only to hospitals or clinics?” These questions are becoming more important given the APRN Consensus Model and given the role that APNs are expected to play across the continua of health care as a result of the PPACA and its reforms. From a regulatory standpoint, the emphasis on a specific population as a focus of practice will lead, when appropriate, to reconceptualizing curricula to ensure that graduates are prepared to succeed in new or revised certification examinations. Hamric (see Chapter 3) has noted that some APN competencies are likely to be performed by nurses in other roles but suggests that the expression of these competencies by APNs is different. For example, all nurses collaborate but a unique aspect of APN practice is that APNs are authorized to initiate referrals and prescribe treatments that are implemented by others (e.g., physical therapy). Innovations and reforms arising from the PPACA will ensure that APNs are explicitly engaged in the delivery of care across care settings, including in nursing clinics and palliative care settings, and as full participants in interprofessional teams. Changes in regulations and in the delivery of health care must and should lead to new or revised conceptualizations of advanced practice nursing, such as defining theoretical and evidence-based differences between APN care and the care offered by other providers and clinical staff, the role of APNs in interprofessional teams, and specialization and subspecialization in advanced practice nursing. This work will enable nursing leaders and health policy makers to design a health care system that delivers high-quality care at reasonable cost based on disciplinary and interdisciplinary competencies, outcomes, effectiveness, efficacy, and costs. Indeed, this textbook reflects a consistent effort to evaluate and revise the authors' conceptualizations of advanced practice nursing based on current contextual factors. The conceptualization advanced in this text has been remarkably stable since it was first proposed in 1996 and has required modest modifications as APN roles and health care have evolved. In addition to a pragmatic reevaluation of advanced practice nursing concepts based on the evolution of APN regulation and health care reform, writers in the United States and abroad are raising important theoretical questions about conceptualizations of advanced practice, including the following: the epistemologic, philosophical, and ontologic underpinnings of advanced practice (Arslanian-Engoren, Hicks, Whall, & Algase, 2005); the nature of advanced practice knowledge, discerning the differences between and among the notions of specialty, advanced practice, and advancing practice (Allan, 2011; Christensen, 2009, 2011; Macdonald, Herbert, & Thibeault, 2006; Thoun, 2011); and the extent to which APNs are prepared to study and apply nursing theories in their practices (Algase, 2010; Arslanian-Engoren, Hicks et al., 2005; Karnick, 2011). In summary, questions arising from a changing health policy landscape and from theorizing about advanced practice nursing point to the need for well thought-out, robust conceptual models to help individuals answer important questions about the phenomenon—in this case, advanced practice nursing. The need for clarity about advanced practice nursing, what it is and is not, is becoming more important, not only for patients and those in the nursing profession but for evolving initiatives such as interprofessional education (CIHC, 2010; Health Professions Networks, 2010; IPEC Expert Panel, 2011), practice (American Association of Nurse Anesthetists, 2012), and creation of accountable care organizations, efforts to build teams and systems in which effective communication, collaboration, and coordination lead to quality care and improved patient, institutional, and fiscal outcomes. Conceptualizations of Advanced Practice Nursing: Problems and Imperatives Despite the usefulness and benefits of conceptual models, some difficulties are apparent in the literature when the clinical and professional issues inherent to advanced practice nursing are examined. Although there is increasing conceptual clarity about advanced practice nursing, five issues of conceptual confusion or uncertainty in the evolution of advanced practice nursing can still be identified. Despite improvements in the area of regulation, the first issue remains the absence of well- defined and consistently applied terms of reference. A core stable vocabulary, a lingua franca, is needed for definition and model building. The lack of a consistent stable vocabulary can be seen in the literature. Shuler and Davis (1993a) have stated that “One of the greatest barriers to using nursing models in [nurse practitioner] practice relates to vocabulary and communication….” Despite progress, this challenge remains. For example, in the United States, advanced practice nursing is the term that is used but the ICN and CNA use the term advanced nursing practice. Furthermore, the role and functions of APNs could be better conceptualized. Although the use of competency is becoming more common, concepts about APN work are variously termed roles, hallmarks, competencies, functions, activities, skills, and abilities. Few models of APN practice address nursing's metaparadigm (person, health, environment, nursing) comprehensively. The problem in comparing, refining, or developing models is that terms are used with no universal meaning or frame of reference; occasionally, no definition is offered at all, or terms are used inconsistently. This instability and inconsistency are evident in many models cited in this chapter. It is rightly anticipated that conceptual models of the field and its practice change over time. However, the evolution of advanced practice nursing and its comprehension by nurses, policymakers, and others will be enhanced if scholars and practitioners in the field agree on the use and definition of fundamental terms of reference. The second issue is that many attempts to articulate models of advanced practice nursing fail to consider extant literature that is directly relevant to such conceptualizing activities. In part, this may be a result of the lag between the conceptualizing effort and its ultimate publication, the knowledge explosion, and the role of the Internet and social media in the generation and dissemination of knowledge. For example, some recently published articles reviewed for this chapter cited work from the 1980s and 1990s; revised publications of these earlier cited works, although apparently available, were not cited. This caution should be considered when proposing, evaluating, or refining advanced practice nursing models. The third issue is a lack of clarity regarding conceptualizations that differentiate between and among levels of clinical practice: • •Does the practice of APNs differ from the practice of registered nurses (RNs) who are experts by experience (i.e., no graduate degree in advanced practice)? • •How does the practice of an APN certified in a subspecialty such as oncology differ from the practice of a non—master's prepared clinician who is certified at the basic level in the oncology subspecialty? • •With the definition of population foci and subspecialty advanced in The APRN Consensus Model, how does certification in one or more subspecialties influence the quality and outcomes of care? • •How does the care provided by an adult health NP with a subspecialty APN certification in oncology or critical care differ from one who is certified in adult health only? Although many authors who write about advanced practice nursing cite Benner's model of expert practice (1984), they rarely indicate that the model was derived from the study of nurses who were primarily experts by experience, not APNs. Certainly, Benner's model is relevant to efforts to conceptualize advanced practice nursing, as demonstrated by Fenton's (1985) and Brykczynski's (1989) work. Given that clinical practice is why the profession of nursing exists and is central to advanced practice nursing, models that help the profession differentiate levels of practice are needed. The fourth issue is the need to clarify the differences between advanced practice nursing and medicine (see Chapter 3). Graduate APN students struggle with this issue as part of role development (see Chapter 4). This lack of conceptual clarity is apparent in advertisements that invite NPs or physician assistants to apply for the same job. As noted in Chapters 21 and 22, organized medicine expends resources in trying to limit or discredit advanced practice nursing, even as some physician leaders work on behalf of advocating for APNs. Hamric, in Chapter 3, asserts that advanced practice nursing is not the junior practice of medicine, an assertion supported by the seven competencies of advanced practice nursing (Chapters 7through 13). Fawcett, a well-respected nursing leader, has asked, “What does it mean to blend nursing and medicine?” (Fawcett et al., 2004; Fawcett & Graham, 2005). Finally, little is understood about the impact of APN-physician collaboration on practice or about strategies for matching the level of knowledge and skill to the needs of patient populations (Brooten & Youngblut, 2006; Calkin, 1984). The fifth issue is interprofessional education and practice, a concept that is central to accountable, collaborative, coordinated, and high-quality care. The development of interprofessional competencies for health professionals (CIHC, 2010; Health Professions Networks, 2010; IPEC Expert Panel, 2011) suggests that the more important questions now are not about “blending” APN and physician practice, but questions such as “How do we ensure that despite differing disciplinary backgrounds, patients, colleagues, and other observers recognize the behavioral expressions of interprofessional competencies?” Also, how do we undertake the conceptual, curricular, credentialing, and other work that will be needed to make interprofessional practice and effective teamwork the gold standard of quality care? The existence of interprofessional competencies and emergence of promising conceptualizations of interprofessional work. (e.g., Barr, Freeth, Hammick, et al., 2005; Reeves, Goldman, Gilbert, et al., 2011) are critical contextual factors for elucidating and advancing conceptualizations of advanced practice nursing. See Chapter 12. Among many imperatives for reaching a conceptual consensus on advanced practice nursing, most important are the interrelated areas of policymaking, licensing and credentialing, and practice, including competencies. In the policymaking arena, for example, not all APNs are eligible to be reimbursed by insurers, and even those activities that are reimbursable are often billed incident to a physician's care, rendering the work of APNs invisible. The APRN Consensus Model (2008), the PPACA, and the IOM's call for changes to enable APNs to work within their full scope of practice (IOM, 2011). will make it easier for U.S. policymakers to recommend and adopt changes to policies and regulations that now constrain APN practice, eventually making the contributions of APNs to quality care visible and reimbursable. Agreement on vocabulary and concepts such as competencies that are common to all APN roles will maximize the ability of APNs to work within their full scope of practice. Although some progress has been made, there are compelling reasons for continuing dialogue and activity aimed at clarifying advanced practice nursing and the concepts and models that help stakeholders understand the nature of APN work and their contributions. Reaching consensus on concepts and vocabulary will serve theoretical, practical, and policymaking purposes. As the work of health care reform and implementing interprofessional competencies, education, and practice moves forward, there will be opportunities for the profession to conceptualize advanced practice nursing more clearly. Clarification and consensus on conceptualization of the nature of advanced practice nursing will lead to the following outcomes: • 1.Clear differentiation of advanced practice nursing from other levels of clinical nursing practice. • 2.Clear differentiation between advanced practice nursing and the clinical practice of physicians and other non-nurse providers within a specialty. • 3.Clear understanding of the roles and contributions of APNs on interprofessional teams, enabling employers to create teams and accountable care organizations that can meet institutions' clinical and fiduciary outcomes. • 4.Clear delineation of the similarities and differences among APN roles and the ability to match APN skills and knowledge to the needs of patients. • 5.Regulation and credentialing of APNs that protects the public and ensures equitable treatment of all APNs. • 6.Clear articulation of international, national, state, and local health policies that do the following: o a.Recognize and make visible the substantive contributions of APNs to quality, cost-effective health care, and patient outcomes. o b.Ensure the public's access to APN care. o c.Ensure explicit and appropriate mechanisms to bill and pay for APN care. • 7.A maximum social contribution by APNs in health care, including improvement in health outcomes and health-related quality of life for the people to whom they provide care. • 8.The actualization of practitioners of advanced practice nursing, enabling APNs to reach their full potential, personally and professionally. Conceptualizations of Advanced Practice Nursing Roles: Organizational Perspectives Practice with individual clients or patients is the central work of the field; it is the reason for which nursing was created. The following questions are the kinds of questions a conceptual model of advanced practice nursing should answer: • •What is the scope and purpose of advanced practice nursing? • •What are the characteristics of advanced practice nursing? • •Within what settings does this practice occur? • •How do APNs' scopes of practice differ from those of other providers offering similar or related services? • •What knowledge and skills are required? • •How are these different from other providers? • •What patient and institutional outcomes are realized when APNs deliver care? how are these outcomes different from other providers? • •When should health care systems employ APNs and what types of patients particularly benefit from APN care? • •For what types of pressing health care problems are APNs a solution in terms of improving outcomes, quality of care, and cost-effectiveness? Some conceptual models reviewed in this chapter are more narrowly focused than others. Some advanced practice models are more homogeneous and some are mixed with respect to the phenomenon studied. Some could be seen as micromodels in terms of the unit of analysis and others could be seen as metamodels, incorporating a number of conceptual frameworks. Some models explain systems; others explain relationships between and among systems. All these foci are important, depending on the purposes to be served. However, in the development of conceptual models, the phenomenon to be modeled must be carefully defined. For example, is the model intended to encompass the entire field of advanced practice nursing, or is it confined to distinctive concepts such as collaborative practice between physicians and APNs? Is advanced nursing practice different from advanced practice nursing? If a phenomenon and its related concepts are not clearly defined, the model could be so inconsistent as to be confusing or so comprehensive that its impact will be diluted. In addition to describing concepts and how they are related, assumptions about the philosophy, values, and practices of the profession should be reflected in conceptual models. The present discussion of conceptualizations of advanced practice nursing is guided by three assumptions: • 1.Each model, at least implicitly, addresses the four elements of nursing's metaparadigm—persons, health and illness, nursing, and the environment. • 2.The development and strengthening of the field of advanced practice nursing depends on professional agreement regarding the nature of advanced practice nursing (a conceptual model) that can inform APN program accreditation, credentialing, and practice. • 3.That APNs meet the needs of society for advanced nursing care. • 4.Advanced practice nursing will reach its full potential to the extent that foundational conceptual components of any model of advanced practice nursing framework are delineated and agreed on. In the next section, the implicit and explicit conceptualizations of advanced practice nursing promulgated by professional organizations concerned with defining APN practice and with clarifying particular APN roles are discussed. Organizations such as the Oncology Nursing Society and the American Association of Critical-Care Nurses [AACN]) have addressed advanced practice nursing in their specialties. Although specialty models and standards are important to students and APNs, they are not addressed in this chapter. As students and readers consider their own APN practices, they may want to review the history of advanced practice nursing (see Chapter 1) and evolving advanced practice nursing roles (see Chapter 5) to inform their efforts to conceptualize their own practices. Although not all the documents described in this section are conceptual models, many imply, describe, or reference a conceptual framework. The APRN Consensus Model (2008) represents a major step forward in promulgating a uniform definition of advanced practice nursing, for the purposes of regulation, in the United States. This accomplishment is informing efforts by other organizations; even so, some problems with the absence of a core vocabulary noted earlier are apparent as one reads the different approaches taken by other professional organizations; therefore, comparisons are difficult to make because terms of reference and their meanings vary. To help the reader appreciate the challenge of developing a common language to characterize advanced practice nursing, dictionary definitions of terms used in conceptualizations of advanced practice nursing are found in Box 2-1. In spite of differences in terminology, the efforts of the profession to deal with a definition of advanced practice nursing are evident in the documents reviewed here. Reflection on and discussion of the various terms used, and debate about interpreting terms such as roles, domains, and competencies, may contribute to the clarification of conceptual models and the emergence of a common language. The descriptions of each model in the following sections are necessarily limited. The reader is encouraged to refer to the original documents and organizations' websites to understand advanced practice nursing as described by organizations and individual authors more fully. Website addresses for national APN organizations are found in Chapter 21. The APRN Consensus Model, the result of collaboration of many organizations, is described first, because it will continue to guide and influence conceptualizations of advanced practice, at least with regard to regulation and credentialing, for the near future. • Competent Having requisite or adequate ability or qualities; legally qualified or adequate; having the capacity to function or develop in a particular way (sufficient) • Competence, competency The quality or state of being competent; the knowledge that enables a person to speak and understand a language • Component A constituent part; ingredient • Domain A sphere of knowledge, influence, or activity • Role A socially expected behavior pattern usually determined by an individual's status in a particular society • Hallmark Distinguishing characteristic, trait, or feature • Sphere An area or range over or within which someone or something acts, exists, or has influence or significance • Scope Space or opportunity for unhampered motion, activity, or thought; extent of treatment, activity, or influence • Standard Something established by authority, custom, or general consent as a model or example; something set up and established by an authority as a rule for the measure of quantity, weight, extent, value, or quality Adapted from Mish, F.C. (Ed.). (2001). Merriam-Webster's collegiate dictionary. (10th ed.). Springfield, MA: Merriam-Webster International; and American Association of Colleges of Nursing (AACN). (2006). The essentials of doctoral education for advanced nursing practice (