evidence-based medicine, p. 339
evidence-based nursing, p. 339
evidence-based practice, p. 339
evidence-based public health, p. 339
grading the strength of evidence, p. 344
meta-analysis, p. 343
randomized controlled trial (RCT), p. 341
research utilization, p. 340
systematic review, p. 343
—See Glossary for definitions
Marcia Stanhope, RN, DSN, FAAN
Dr. Marcia Stanhope is currently employed at the University of Kentucky College of Nursing, Lexington, Kentucky. She holds the Good Samaritan Foundation Chair and Professorship in Community Health Nursing. She has taught evidence-based practice courses, community health, public health, epidemiology, policy, primary care nursing, and administration courses. Dr. Stanhope formerly directed the Doctorate of Nursing Practice program of the College of Nursing at the University of Kentucky. In this role she developed evidence-based practice courses and implemented such practice in two nurse-managed centers. She has been responsible for both undergraduate and graduate courses in population-centered nursing. She has also taught at the University of Virginia and the University of Alabama, Birmingham. Her presentations and publications have been in the areas of home health, community health and community-focused nursing practice, and primary care nursing, including evidence-based practice.
Emphasis on evidence-based practice (EBP) is a recent development in health care delivery in the United States. It is a relevant approach to providing the highest quality of health care in all settings, which will result in improved health outcomes. EBP is important for all professionals who work in social and health care environments, regardless of the client or the setting with which professionals are dealing, including public health nurses who work with populations. Emphasis on EBP has resulted from increased expectations of consumers, changes in health care economics, increased expectations of accountability, advancements in technology, the knowledge explosion fueled by the Internet, and the growing number of lawsuits occurring when there is injury or harm as a result of practice decisions that are not based on the best available evidence (Leufer and Cleary-Holdforth, 2009). Nurses at all levels have an opportunity to improve the practice of nursing and client outcomes. The Institute of Medicine has set a goal that by 2020, the best available evidence will be used to make 90% of all health care decisions, yet most nurses continue to be inconsistent in implementing EBP. An even greater concern in public health is that the field is lagging behind in developing evidence-based guidelines for the community setting. It is important to recognize that regardless of the level of education, undergraduate or graduate, nurses can be involved in the development, implementation, and evaluation of the effects of EBP (Green, 2006; Melnyk, 2009; Olsen et al, 2007; Pravikoff, 2005; Vanhook, 2009).
Definition of Evidence-Based Practice
The term evidence-based was first attributed to Gordon Gyatt, a Canadian physician at McMaster University in 1992 (Evidence Based Medicine Working Group, 1992). The term was first applied in medicine to begin the development of new ways of guiding professional decision making by using the best available evidence. Because the concept was developed in medicine, some of the first definitions focused on evidence-based medicine.
The definition of evidence-based medicine by Sackett and associates (Sackett et al, 1996) became the industry standard. Sackett et al (1996) defined evidence-based medicine as “the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual clients” (p 71). Without current best external evidence, they said, “practice risks become rapidly out of date, to the detriment of clients” (Sackett et al, 1996, p 72). A more succinct definition was proposed as the conscientious use of the current best evidence in making decisions about patient care (Sackett et al, 2000).
Adapting the definition by Sackett et al (1996), Rychetnik et al (2003) defined evidence-based public health as “a public health endeavor in which there is an informed, explicit, and judicious use of evidence that has been derived from any of a variety of science and social science research and evaluation methods” (p 538). Brownson et al (2009) recently expanded the definition of evidence-based public health to include “making decisions on the basis of the best available evidence, using data and information systems, applying program planning frameworks, engaging the community in decision making, conducting evaluations, and disseminating what has been learned” (p 175).
In a position statement on EBP, the Honor Society of Nursing, Sigma Theta Tau International, defined evidence-based nursing as “an integration of the best evidence available, nursing expertise, and the values and preferences of the individuals, families, and communities who are served” (Honor Society of Nursing, Sigma Theta Tau International, 2005). The definition continues to be broadened in scope and now includes a life-long problem-solving approach to clinical practice, integrating both external and internal evidence to answer clinical questions and to achieve desired client outcomes (Melnyk and Fineout-Overholt, 2011). External evidence includes research and other evidence, whereas internal evidence includes the nurse’s clinical experiences and the client’s preferences.
Applied to nursing, evidence-based practice includes the best available evidence from a variety of sources including research studies, nursing experience and expertise, and community leaders. Culturally and financially appropriate interventions need to be identified when working with communities. The use of evidence to determine the appropriate use of interventions that are culturally sensitive and cost-effective is essential.
History of Evidence-Based Practice
During the mid to late 1970s, there was growing consensus among nursing leaders that scientific knowledge should be used as a basis for nursing practice. During that time, the Division of Nursing in the U.S. Public Health Service began funding research utilization projects. Research utilization has been defined as “the process of transforming research knowledge into practice” (Stetler, 2001, p 272) and “the use of research to guide clinical practice” (Estabrooks, Winther, and Derksen, 2004, p 293).
Three projects funded by the Division of Nursing received the most attention and were the most influential in shaping nursing’s view of using research to guide practice: the Nursing Child Assessment Satellite Training Project (NCAST) (Barnard and Hoehn, 1978; King, Barnard, and Hoehn, 1981), the Western Interstate Commission for Higher Education (WICHE) Regional Program for Nursing Research Development (WICHEN) (Krueger, 1977; Krueger, Nelson, and Wolanin, 1978; Lindeman and Krueger, 1977), and the Conduct and Utilization of Research in Nursing Project (CURN) (Horsley, Crane, and Bingle, 1978; Horsley et al, 1983). Using very different approaches and methods, each project tested interventions to facilitate research use in practice.
Although nursing continued to focus on research utilization projects, medicine also began to call for physicians to increase their use of scientific evidence to make clinical decisions. In the late 1970s, David Sackett, a medical doctor and clinical epidemiologist at McMaster University, published a series of articles in the Canadian Medical Association Journal describing how to read research articles in clinical journals. The term critical appraisal was used to describe the process of evaluating the validity and applicability of research studies (Guyatt and Rennie, 2002). Later, Sackett proposed the phrase “bringing critical appraisal to the bedside” to describe the application of evidence from medical literature to client care. This concept was used to train resident physicians at McMaster University and evolved into a “philosophy of medical practice based on knowledge and understanding of the medical literature supporting each clinical decision” (Guyatt and Rennie, 2002, p xiv).
With Gordon Guyatt as Residency Director of Internal Medicine at McMaster, the decision was made to change the program to focus on “this new brand of medicine” that Guyatt eventually called evidence-based medicine (Guyatt and Rennie, 2002, p xiv). Guyatt and Rennie described the goal of evidence-based medicine as being “aware of the evidence on which one’s practice is based, the soundness of the evidence, and the strength of inference the evidence permits” (2002, p xiv).
In 1992 the Evidence-Based Medicine Working Group published an article in the Journal of the American Medical Association expanding the concept of evidence-based medicine and calling it a paradigm shift. A paradigm shift simply means a change from old ways of knowing to new ways of knowing and practicing. Ways of knowing in nursing have included the empirical knowledge, or the science of nursing; the aesthetic knowledge, or the art of nursing; personal knowledge, or interpersonal relationships and caring; and ethical knowledge, or moral and ethical codes of conduct usually established by professional organizations (Bradshaw, 2010). Nursing practice has often focused less on science and more on the other four ways of knowing described here.
According to the Working Group (Evidence-Based Medicine Working Group, 1992), the old paradigm viewed unsystematic clinical observations as a valid way for “building and maintaining” knowledge for clinical decision making (p 2421). In addition, principles of pathophysiology were seen as a “sufficient guide for clinical practice” (p 2421). Training, common sense, and clinical experience were considered sufficient for evaluating clinical data and developing guidelines for clinical practice. The Working Group cited developments in research over the past 30 years as providing the foundation for the paradigm shift and a “new philosophy of medical practice” (p 2421).
The new paradigm, evidence-based medicine, acknowledged clinical experience as a crucial, but insufficient, part of clinical decision making. Systematic and unbiased recording of clinical observations in the form of research will increase confidence in the knowledge gained from clinical experience. Principles of pathophysiology were seen as necessary but not sufficient knowledge for making clinical decisions. The Working Group emphasized that physicians needed to be able to critically appraise the research literature in order to appropriately apply research findings in practice. Knowledge gained from authoritative figures was also deemphasized in the new paradigm (Working Group, 1992).
In the years since the Working Group began, the term evidence-based practice has been proposed as a term to integrate all health professions. The underlying principle was that high-quality care is based on evidence rather than on tradition or intuition (Beyers, 1999).
Nurses have always used various resources for problem solving. Intuition, trial and error, tradition, authority, institutional standards, prior knowledge, and clinical experience have often been used as the basis for decision making in clinical settings. However, not all of these resources are reliable and all have not consistently produced desired outcomes (Bradshaw, 2010). A procedure performed based on intuition or trial and error might be performed successfully sometimes and not at other times. For example, tradition and authority, which comes from texts and policy and procedure manuals, can lead to faulty clinical decision making. Institutional standards are developed by accrediting agencies (e.g., The Joint Commission), by licensing agencies, and by professional organizations. These standards have been developed in the past primarily by expert opinion and past experiences. The standards may not reflect the best practices in the current environment or from the literature. Although prior knowledge gained in educational programs, through continuing education, or through experience can be a good teacher, it can also contain bias and quickly become outdated unless a nurse participates in constantly refreshing knowledge. For example, just because a nurse has experience in successfully performing an intervention a certain way today does not mean it is the best way or that it will be successful every time and in the future unless practices are changed based on the most current data.
When EBP was first emphasized in medicine, the focus was on the answer to clinical questions concerning an individual client problem in order to provide the best diagnosis to implement the best treatment. When nursing became involved in EBP, the focus seemed to shift to answering a clinical question about a health problem experienced by a group of clients (Levin et al, 2010).
The current nursing literature on EBP is primarily associated with applications in the acute and primary care settings and little is reported about its use in community settings. However, the basic principles of EBP can be applied at the individual level or at the community level. Although definitions of EBP vary widely in the literature, the common thread across disciplines is the application of the best available evidence to improve practice (Leufer and Cleary-Holdforth, 2009).
EBP has been described as both a process and a product (Bradshaw, 2010; Scott and McSherry, 2009). The product is the use of evidence to make practice changes, whereas the process is a systematic approach to locating, critiquing, synthesizing, translating, and evaluating evidence upon which to base practice changes. Scott and McSherry (2009) engaged in a process using an extensive literature review to arrive at a definition of evidence-based nursing and to differentiate the definition from evidence-based practice. Based on their review they arrived at the following definition: evidence-based nursing is a process whereby evidence, nursing theory, and the nurse’s clinical expertise, are evaluated and used in conjunction with the client’s involvement, to make critical decisions about the best care for the client. Continuous evaluation of the implementation of care is essential to make clinical decisions about client care for the best possible outcomes.
Types of Evidence
No matter which definition of EBP is supported, what counts as evidence has been the issue most hotly debated. A hierarchy of evidence, ranked in order of decreasing importance and use, has been accepted by many health professionals. The double-blind randomized controlled trial (RCT) generally ranks as the highest level of evidence followed by other RCTs, non-randomized clinical trials, quasi-experimental studies, case-controlled reports, qualitative studies, and expert opinion (Russell-Babin, 2009). Some nurses would argue that this hierarchy ignores evidence gained from clinical experience. However, the definition of evidence-based nursing presented above indicates that clinical expertise as evidence, when used with other types of evidence, is used to make clinical decisions. Also in the hierarchy of evidence, expert opinion can be gained from non-research–based published articles, professional guidelines, national guidelines, organizational opinions, and panels of experts, as well as the nurse’s clinical expertise. Since it is difficult to find or perform RCTs in the community, other types of evidence have been highlighted as the best evidence in public health literature upon which to base evidence-based public health practice: scientific literature found in systematic reviews, scientific literature used or quoted in one or more journal articles, public health surveillance data, program evaluations, qualitative data obtained from community members and other stakeholders, media/marketing data such as the results of a media campaign to reduce smoking, word of mouth, and personal/professional experience (Brownson et al, 2009).
Factors Leading to Change or Barriers to Evidence-Based Practice
EBP represents a cultural change in practice. It provides an environment to improve both nursing practice and client outcomes. Nursing is known for providing care based on environmental and client assessments, critical observations, development of questions or hypotheses to be explored, the collecting of data from the environment through community or organizational assessments, or the client through history, physical assessment, and review of past heath records, analyzing the data to develop plans of care, whether for the individual client, family, group or community, and drawing conclusions upon which to base care for the purpose of improving client outcomes (Vanhook, 2009). However, several factors have been identified in the literature that support implementation of EBP or that will need to be overcome for nursing and other disciplines to successfully implement EBP. These factors include the following:
Although a community agency may subscribe in theory to the use of EBP, actual implementation may be affected by the realities of the practice setting. Community-focused nursing agencies may lack the resources needed for its implementation in the clinical setting, such as time, funding, computer resources, and knowledge. Nurses may be reluctant to accept findings and feel threatened when long-established practices are questioned. Cost can also be a barrier if the clinical decision or change will require more funds than the agency has available. Compliance can be a barrier if the client will not follow the recommended intervention. Public health departments are moving toward EBP and are seeking accreditation through the national public health accreditation board. The accreditation process will be ready in 2011.
Steps in the Evidence-Based Practice Process
EBP is a philosophy of practice that respects client values. Melnyk and Fineout-Overholt (2010) have described a seven-step EBP process:
Yes, their first step is step zero. This process was initially described as a five-step process by others (Dawes et al, 2004; Dicenso et al, 2005; Craig and Smyth, 2007). The unique features of the Melnyk et al model is the emphasis on the spirit of inquiry and the sharing of the results of the process.
Step zero involves a curiosity about the interventions that are being applied. Do they work, or is there a better approach? In public health nursing, for example, are there better parenting outcomes if the parents attend classes at the health department? Or are home visits to new mothers and babies more effective for achieving a healthy baby? Step one requires asking questions in a “PICOT” format. Although Melnyk et al have developed a specific process for the PICOT, the process was first described by Sackett (1996), who discussed the need to define the (P)opulation of interest, the (I)ntervention or practice strategy in question, the population or intervention to be used for (C)omparision, the (O)utcome desired, and the (T)ime frame. Step two involves searching for the best evidence to answer the question. This step involves searching the literature. In the case of the example above, a literature search would focus on a search of key terms like public health nursing, parenting of new babies, parenting classes, and home visits. Step three requires a critical appraisal of the evidence found in step two. To appraise the literature found, Melnyk suggests asking three questions about each of the articles found in the literature search: (1) the validity, (2) the importance, and (3) whether or not the results of the article will help you as a nurse provide quality care for your clients. Step four is the step in which the evidence found is integrated with clinical expertise and client values. Institutional standards and practice guidelines, as well as cost of care and support of the health care environment to implement the findings, are all factors considered in this step. Step five requires an evaluation of the outcomes of practice decisions and changes that were based on the answers to the first four steps. The goal in evaluation is a positive change in quality of care and health care outcomes. In the example of group parenting classes versus home visits to new mothers and babies, current literature suggests improved quality and health care outcomes with home visits (The Pew Center, 2010).
Step six is disseminating outcomes of the results to others, to colleagues, to the employing agency’s administration, to faculty and other students, and through a poster or podium presentation of the student nurse organizations, or professional organizations. Professional organizations often sponsor student presentations for undergraduates as well as graduate students. Sharing of information is most important because it prevents each individual nurse from trying to find the best answer to the same question answered by someone else, and it gives us the basis for asking new questions. Sharing makes practice more efficient and improves quality and health care outcomes.
In a busy community practice setting, it is often difficult for nurses to access evidence-based resources. Using evidence-based clinical practice guidelines is one way for nurses to provide evidence-based nursing care in an efficient manner. Clinical practice guidelines are usually developed by a group of experts in the field who have reviewed the evidence and made recommendations based on the best available evidence. The recommendations are usually graded according to the quality and quantity of the evidence. The Public Health Practice Reference is an example of practice guidelines developed for population-centered nurses’ use.
Approaches to Finding Evidence
Returning to the previous example, the clinical question has been stated and the population has been defined as new mothers and babies. Two interventions will be compared. The outcome is stated as healthy babies and the time frame may be 6 months or 1 year, or another time at which the outcomes of the interventions will be evaluated.
Four approaches are described that allow the nurse to read research/non-research evidence in a condensed format. The first, a systematic review, is “a method of identifying, appraising, and synthesizing research evidence. The aim is to evaluate and interpret all available research that is relevant to a particular research question” (Rychetnik et al, 2003, p 542). A systematic review is usually done by more than one person and describes the methods used to search for the evidence and evaluate the evidence. Systematic reviews can be accessed from most databases, such as Medline and CINAHL. The Cochrane Library is an electronic database that contains regularly updated evidence-based health care databases maintained by the Cochrane Collaboration, a not-for-profit organization (www.cochrane.org). The Cochrane Library is composed of three main branches: systematic reviews, trials register, and methodology database. The Cochrane Library publishes systematic reviews on a wide variety of topics. Systematic reviews differ from traditional literature review publications in that systematic reviews require more rigor and contain less opinion of the author. Systematic reviews for public health can be found in the Guide to Community Preventive Services, the Cochrane Public Health Group, the Center for Reviews and Dissemination, and the Campbell Collaboration (Box 15-1).