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Clinical Nursing Skills

1.2 Evidence-Based Practice

Clinical Nursing Skills1.2 Evidence-Based Practice

Learning Objectives

By the end of this section, you will be able to:

  • Analyze how different theories influence nursing knowledge
  • Describe how nursing research has evolved
  • Identify the steps for translating evidence-based research into evidence-based practice

This section will explore the world of nursing theory and how it has shaped evidence-based practice (EBP) and the nursing profession as a whole. As nursing evolved from reliance on complete medical direction into independent professional practice, nursing theories were developed by leaders in the field to shape nursing practice into what it is today. This section will guide you through these important aspects, helping you grasp the connections between theory, research, and practice.

Interdisciplinary Theories Used in Nursing

A theory that integrates knowledge and concepts from one or more disciplines to enhance nursing practice, research, and education is known as an interdisciplinary theory. These are an essential part of nursing as they provide a broader perspective and more comprehensive understanding of healthcare issues.

In nursing, interdisciplinary theories are used in various ways. They assist in the development of nursing models and frameworks that guide the delivery of patient care. By incorporating theories from disciplines such as psychology, sociology, and biology, nurses can better understand the complex factors influencing health and apply holistic approaches to patient care.

Interdisciplinary theories also facilitate collaboration among healthcare professionals from various disciplines. Nurses frequently work as part of interdisciplinary teams, including physicians, therapists, social workers, and others. By understanding and integrating theories from different fields, nurses can effectively communicate and collaborate with team members, promoting coordinated and holistic patient care.

General Systems Theory

The general systems theory is a conceptual framework that describes how systems function and interact with their environment (American Psychological Association, 2023). General systems theory views the world not as a collection of individual elements operating independently, but as a network of interconnected systems. A system is defined as a set of elements that are interrelated and work together to achieve a common goal. An element can be an object, person, process, or concept. General systems theory emphasizes the interdependence, relationships, and dynamics within and between systems.

General systems theory is highly beneficial in healthcare settings as it provides a holistic perspective and promotes a comprehensive understanding of complex healthcare systems. It encourages healthcare professionals to view the entire system, including patients, healthcare providers, and community resources, as interconnected components. By adopting a systems thinking approach, healthcare teams can analyze the relationships and interdependencies within the system, identify patterns, and address underlying causes of problems.

Adaptation Theory

Roy’s adaptation model, developed by nursing theorist Sister Callista Roy, is a conceptual framework based on the belief that individuals strive to maintain balance and achieve a state of equilibrium in response to changes in their internal and external environments, and aims to promote adaptation for optimal health and well-being (Marudhar & Josefina, 2019).

According to Roy’s adaptation model, adaptation is influenced by both internal and external stimuli. An internal stimulus includes physiological, psychological, and cognitive factors, while an external stimulus encompasses the physical, social, and cultural aspects of the environment.

Roy’s model proposes four major adaptive modes: physiological, self-concept, role function, and interdependence. These adaptive modes represent different aspects of an individual’s life and are interconnected (Figure 1.4). The model also highlights the importance of coping strategy mechanisms and the role of the nursing profession in facilitating adaptive responses.

Nurses using Roy’s adaptation model assess individuals’ adaptive responses, identify stimuli that may disrupt adaptation, and intervene to promote adaptation. Interventions may include modifying the environment, providing education and support, or assisting individuals in developing effective coping strategies. See 1.1 Principles of Nursing Practice for a more detailed description of strategies that nurses can give to their patients to help promote adaptation and adapt effective coping strategies.

Diagram showing Roy’s adaptation model, including coping mechanisms, stimuli, adaptive behavior, physiological-physical, interdependence, self-concept; group identity, and role function.
Figure 1.4 Roy’s adaptation model shows how different aspects of an individual’s life determine adaptability. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)

Developmental Theory

A developmental theory is a framework that aims to explain and understand how individuals grow, change, and develop across various stages of life, emphasizing the interaction between biological, cognitive, social, and emotional factors in shaping human development. Erik Erikson’s psychosocial development theory and Abraham Maslow’s hierarchy of needs theory are two of the most important developmental theories that have influenced nursing theory.

Erikson’s psychosocial development theory outlines eight stages of human development, each characterized by a unique psychosocial crisis or challenge (Orenstein & Lewis, 2022). These stages span from infancy to old age and emphasize the importance of successfully resolving these crises for healthy psychosocial development (Figure 1.5). Nursing theories influenced by Erikson’s model recognize the significance of addressing psychosocial aspects of patient care, such as identity, intimacy, and generativity. These theories focus on promoting patients’ psychological well-being, fostering positive relationships, and supporting patients in their developmental journeys. Examples include Jean Watson’s caring science and human caring theory, Imogene King’s theory of goal attainment, and Betty Neuman’s systems model.

Diagram showing Erik Erikson’s stages of psychological development: (Stage 1) Infancy, Trust vs. Mistrust; (Stage 2) Early childhood, Autonomy vs. Shame/doubt; (Stage 3) Preschool age, Initiative vs. Guilt; (Stage 4) School age, Industry vs. Inferiority; (Stage 5) Adolescence, Identity vs. Role confusion; (Stage 6) Young adulthood, Intimacy vs. Isolation; (Stage 7) Middle adulthood, Generosity vs. Stagnation; (Stage 8) Maturity, Ego integrity vs. Despair.
Figure 1.5 Erik Erikson’s stages of psychological development show the different psychosocial crisis or challenge presented at every stage of life. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)

On the other hand, Maslow’s hierarchy of needs theory posits that individuals have a hierarchical structure of needs, ranging from basic physiological needs to self-actualization (Toney-Butler & Thayer, 2023). This theory suggests that individuals must fulfill their basic physiological and safety needs before progressing to higher-level needs such as belonging, self-esteem, and self-actualization. Nursing theories inspired by Maslow’s model prioritize providing holistic care that addresses patients’ physiological, psychological, and social needs. Examples include Hildegard Peplau’s theory of interpersonal relations, Virginia Henderson’s nursing theory, Madeleine Leininger’s culture care theory, and Sister Callista Roy’s adaptation model.

These theories emphasize the importance of creating a supportive and nurturing environment that promotes patients’ well-being and enables them to reach their full potential. Figure 1.6 depicts Maslow’s hierarchy and illustrates the various human needs encompassed by holistic care.

Diagram showing Maslow’s hierarchy: (Physiological needs) Food, water, shelter; (Security) Safety, work, financial well-being; (Social needs) Belonging, love, family, friendship; (Esteem) Accomplishment, self-worth, respect; (Self-actualization) Personal growth, development of potential.
Figure 1.6 According to Maslow, food and water are among the most basic human needs; they must be met before people can fulfill needs higher in the hierarchy. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)

Both Erikson’s and Maslow’s theories have influenced nursing theorists in recognizing the importance of addressing the multidimensional needs of patients. They have contributed to the development of nursing theories that embrace a holistic perspective, acknowledging the influence of psychological, social, and developmental factors on patients’ health and well-being.

Nursing Theory

The nursing theory refers to a set of organized concepts, principles, and relationships that guide and inform nursing practice. It is a systematic and evidence-based framework developed by nursing theorists to describe, explain, predict, and prescribe nursing care. Ultimately, nursing theories shape how nurses interact with their patients.

Framework of Nursing Theory

The framework of nursing theory provides a structured and organized approach to understanding and applying nursing concepts and principles. It serves as the foundation (Table 1.1) upon which nursing theories are built and helps to organize and categorize nursing knowledge.

Key Components of Nursing Theory Framework Definition
Concepts Concepts are the building blocks of nursing theory. They are abstract ideas or phenomena that represent various aspects of nursing practice and patient care. Examples of nursing concepts include health, environment, nursing process, adaptation, and caring.
Propositions Propositions are statements that describe the relationships between concepts within a nursing theory. They articulate the connections and interactions between different elements of the theory and provide a basis for understanding and explaining nursing situations.
Assumptions Assumptions are underlying beliefs or values that guide the development and application of nursing theory. They are the foundation upon which theories are built and shape the perspective and approach of the theory. Assumptions may relate to the nature of health, the role of the nurse, or the influence of the environment, among others.
Models or frameworks Some nursing theories are presented in the form of models or frameworks that provide a visual representation of the theory’s key concepts, relationships, and processes. These models or frameworks offer a visual guide for understanding and applying the theory in practice.
Table 1.1 Key Components and Definitions of Nursing Theory Framework

The framework of nursing theory is dynamic and evolves as new knowledge and evidence emerge. Nursing theories and their frameworks contribute to the development of EBP, improve patient outcomes, and enhance the professional identity and autonomy of the nursing profession. There are two main types of nursing theories: descriptive and prescriptive.

Descriptive Theories

A descriptive theory in nursing, also known as phenomenological theories, focuses on describing and understanding the lived experiences of individuals in the context of health care (Watkins, 2020). These theories aim to provide a deeper understanding of the meaning and significance of various phenomena related to health, illness, and nursing care.

Descriptive nursing theories often employ qualitative research methods to explore and analyze the subjective experiences, perspectives, and perceptions of patients, families, and healthcare providers. They seek to uncover the essence of these experiences and the underlying meanings attributed to them. These theories may explore topics such as the experience of chronic illness, the process of decision-making in health care, the impact of cultural beliefs on health behaviors, or the challenges faced by nurses in providing end-of-life care. They delve into the lived experiences of individuals to gain insights into the complexity and nuances of healthcare phenomena.

Leininger’s theory of culture care diversity and universality is an example of a descriptive nursing theory. This theory focuses on describing the impact of cultural beliefs, values, and practices on health and nursing care (McFarland & Wehbe-Alamah, 2019). It explores how individuals from different cultural backgrounds experience and perceive health, illness, and health care, highlighting the importance of cultural competence in nursing practice.

Prescriptive Theories

A prescriptive theory in nursing provides guidance and direction for nursing practice by offering recommendations, interventions, or guidelines to achieve desired outcomes (Watkins, 2020). These theories focus on prescribing actions or strategies that nurses can implement to promote health, prevent illness, and facilitate healing. One example of a prescriptive nursing theory is Watson’s theory of human caring. Watson’s theory emphasizes the significance of caring in nursing practice (Watson Caring Science Institute, 2023). It prescribes that nurses should demonstrate genuine caring attitudes, compassion, and empathy toward patients. Nurses then integrate caring behaviors into their interactions, creating a healing environment that nurtures the physical, emotional, and spiritual well-being of patients.

Concepts of Nursing Theories

The nursing metaparadigm refers to the four foundational concepts that are central to the discipline of nursing (Deliktas et. al, 2019). These concepts are person, environment, health, and nursing. They form the overarching framework that guides nursing theory, research, and practice (Figure 1.7). The nursing metaparadigm guides nurses in understanding the interconnectedness of the person, environment, health, and nursing, and serves as a foundation for delivering patient-centered and evidence-based care.

Diagram showing the four concepts of the nursing metaparadigm: (Person) Recipient of care; (Nursing) Characteristics of the person providing care; (Environment) Setting for care; (Health) Stage of wellness.
Figure 1.7 The four concepts of the nursing metaparadigm are interconnected and provide the foundation for effective patient care. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)


The person refers to the individual, family, group, or community receiving nursing care. It recognizes that each person is unique, with physical, emotional, social, and spiritual dimensions. Nurses support the concept of person by considering the patient’s beliefs, values, and preferences when developing a plan of care.


The environment encompasses the physical, social, cultural, and economic settings in which the person exists. It includes both the immediate healthcare setting and the broader societal and environmental factors that can influence health outcomes. Nurses support the concept of environment by recognizing the impact of the environment on the patient’s well-being and working to create a supportive, safe, and healing environment.


Health encompasses the physical, mental, and social well-being of the person. It goes beyond the absence of illness and emphasizes optimal functioning and quality of life. Nurses support the concept of health by providing education and preventive care, managing symptoms, and facilitating the person’s overall well-being.


Nursing is the art and science of providing care to individuals, families, communities, and populations. It involves the application of knowledge, skills, and compassion in promoting and maintaining health, preventing illness, and supporting individuals in their healing processes. Nursing is characterized by utilizing a unique body of knowledge, ethical principles, and commitment to provide holistic care.

Evolution of Nursing Research

Nursing research has undergone significant evolution over time, transitioning from a tradition-based practice to a scientifically rigorous discipline. Initially, nursing relied on personal experience and tradition, but beginning in the nineteenth century, the need for evidence-based practice became evident (U.S. Department of Health and Human Services, n.d.). The term evidence-based practice (EBP) refers to the integration of the best available research information, clinical expertise, and patient preferences or values to guide healthcare decision-making and improve patient outcomes (American Nurses Association (ANA), 2023). With the establishment of research organizations and journals, nursing research gained recognition and contributed to the improvement of patient care. The adoption of different kinds of research methodologies allowed for more robust investigations into nursing education, practice improvement, and patient outcomes. The emergence of EBP (Table 1.2) further integrated research findings into nursing practice, ensuring that decisions are based on the best available evidence. Nursing research has expanded its focus to encompass diverse topics such as chronic illness management, mental health, and healthcare disparities. Technological advancements and interdisciplinary collaborations continue to shape the evolution of nursing research, further advancing the field and its impact on patient care.

ANA Standard 13, Evidence-Based Practice and Research
The ANA’s Standards of Professional Performance are a set of guidelines that outline the behaviors and competencies expected of nurses in their professional roles. These standards encompass various domains, including quality of care, professional practice evaluation, education, collaboration, ethics, research, resource utilization, leadership, and advocacy.
Standard 13, Evidence-Based Practice and Research, states “the registered nurse integrates evidence and research findings into practice” (American Nurses Association, 2021).
The ANA Standard 13 on Evidence-Based Practice and Research is an indispensable cornerstone of nursing practice. This standard is paramount because it emphasizes the integration of the best available evidence into clinical decision-making. By adhering to Standard 13, nurses are equipped with the tools to critically appraise research, identify relevant findings, and translate them into evidence-based interventions. This elevates nursing practice by ensuring that patient care is grounded in scientifically sound principles. Moreover, embracing evidence-based practice fosters a culture of lifelong learning and professional growth. By implementing this standard, nurses become steadfast advocates for quality and safety, driving the delivery of patient-centered care.
Table 1.2 ANA Standard 13

Protection of Human Rights in Nursing Research

The protection of human rights is of utmost importance in nursing research to ensure the ethical treatment of participants and uphold their dignity, privacy, and well-being (Burke, 2023c). Several principles and guidelines are in place to safeguard human rights during the research process:

  • Informed consent: Obtaining informed consent is a fundamental requirement in nursing research. Participants must be provided with comprehensive information about the study, including its purpose, procedures, risks, benefits, and their right to withdraw at any time. Informed consent ensures that individuals can make voluntary and autonomous decisions about their participation.
  • Confidentiality and privacy: The ethical and legal duty to safeguard and protect sensitive and private information from unauthorized disclosure or access, ensuring it remains secure from others is known as confidentiality. Respecting the confidentiality and privacy of research participants is crucial. Nurses must take measures to protect participants’ identities and ensure that data are handled securely. Confidentiality allows individuals to share sensitive information without fear of it being disclosed to unauthorized individuals.
  • Beneficence and nonmaleficence: Nursing researchers have an ethical obligation to promote the well-being of participants (beneficence) and minimize any potential harm (nonmaleficence). This includes carefully designing research protocols, minimizing risks, and monitoring participants’ welfare throughout the study.
  • Research ethics committees: Institutional review boards or research ethics committees play a vital role in safeguarding human rights in nursing research. These committees review research protocols to ensure that ethical principles are upheld, participants’ rights are protected, and potential risks are minimized.
  • At-risk populations: Special considerations must be given when conducting research involving at-risk populations. The term at-risk population refers to a group of individuals who are at higher risk of experiencing adverse health, social, or economic outcomes due to various factors such as limited access to resources, socioeconomic disparities, or health conditions. This includes children, older adults, individuals with cognitive impairments, or those with limited decision-making capacity. Extra safeguards are necessary to protect the rights and welfare of these individuals.
  • Ethical guidelines and standards: Nursing research adheres to ethical guidelines and standards and national regulatory bodies’ guidelines. These documents provide ethical frameworks and principles that guide researchers in conducting ethical and responsible research.

By upholding the protection of human rights in nursing research, nurses contribute to the integrity, validity, and ethical conduct of research. Ensuring participants’ autonomy, privacy, confidentiality, and overall well-being enhances the trustworthiness of research findings and upholds the ethical principles central to the nursing profession.

Methodology of Nursing Research

Nursing research methodology uses both quantitative and qualitative research methods (Figure 1.8). The quantitative research refers to a systematic and empirical approach that involves the collection, analysis, and interpretation of numerical data to answer research questions and explore phenomena related to health care. Quantitative research provides numerical data and statistical analysis, allowing for objective measurements, generalizations, and statistical significance. It helps identify trends, assess treatment effectiveness, and inform evidence-based practice.

On the other hand, qualitative research in nursing refers to a systematic and subjective approach that focuses on understanding and interpreting human experiences, meanings, and social phenomena in the context of health care. Qualitative research explores the subjective experiences, perspectives, and meanings behind healthcare phenomena through in-depth interviews, observations, and narratives. It provides rich, contextual insights into patients’ lived experiences, healthcare provider interactions, and social determinants of health. By combining both approaches, nurses can obtain a holistic view of patient care, integrating objective data with the humanistic aspects of health care (Curtis et al., 2016).

Table showing differences between Qualitative Questions and Quantitative Questions; Qualitative questions: (Purpose) To explain why or how, (Data type) Subjective and open to interpretation, (Approach) Observation and interviews, (Analysis) Grouping and categorization; Quantitative questions: (Purpose) To determine how many or how much, (Data type) Fixed and numerical or statistical, (Approach) Measuring and counting, (Analysis) Statistical analysis.
Figure 1.8 Nursing research methodology uses both quantitative and qualitative research methods. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)

Quantitative Research

Quantitative research is a methodical investigation that utilizes statistical analysis and objective measurements to generate numerical findings. Statistical analysis techniques are used to summarize the data, draw conclusions, and test hypotheses. Quantitative research aims to identify patterns, relationships, and associations between variables (Table 1.3). The results of quantitative research are presented using statistical tables, charts, and statistical measures such as means, percentages, correlations, or regression analyses.

Type Description
Correlational The researcher aims to identify a relationship between two variables, without any outside influence (extraneous variables). A positive correlation means both variables change in the same direction, a negative correlation means the variables change in opposite directions, and a zero correlation means there is no relationship observed.
Descriptive The researcher observes and measures variables in order to identify trends, or to understand a population, phenomenon, or situation.
Experimental The researcher aims to identify the relationship between two or more variables using the scientific method. The researcher has control over the extraneous variable, and can recreate and verify the outcomes.
Quasi-experimental The researcher aims to identify a relationship between two variables, but participants are placed in random groups (extraneous variables) to compare results.
Survey The researcher uses surveys to collect information. Cross-sectional surveys are given at any point in time; Longitudinal surveys are given for various durations of time.
Table 1.3 Examples of Quantitative Research Approaches (Source: Taherdoost, 2022.)

In quantitative nursing research, researchers use data collection instruments, such as surveys, questionnaires, or structured observations, to gather data from a sample or population. The collected data are typically in the form of numerical values or categorical responses. An example of quantitative research would be a hospital giving surveys to patients upon discharge, asking them to rate their experience on a numerical scale of 0 to 10, and then evaluating the responses to see which areas most need improvement.

Qualitative Research

Qualitative research is a methodological approach that emphasizes exploring the depth, complexity, and richness of individuals’ perspectives and the social context in which they occur.

In qualitative nursing research, researchers use various data collection methods, such as interviews, focus groups, observations, or document analysis, to gather non-numerical data. The data collected often consist of words, narratives, descriptions, and images that provide a detailed understanding of the participants’ experiences, beliefs, and perceptions (Table 1.4).

Type Description
Ethnography The researcher is directly involved/immersed in the participant’s environment; different data techniques are used to document the behaviors, actions, and events of the research population.
Grounded theory The researcher observes or studies a population, and then develops a comparative analysis based on studied social interactions and experiences.
Phenomenology The researcher looks into “lived experiences” of the participants, and focuses on examining why the participant behaved a certain way from the perspective of the participant who experienced it.
Narrative The researcher strings together a sequence of events, usually from just one or two participants, to create a narrative, or cohesive story.
Table 1.4 Examples of Qualitative Research Approaches (Source: Tenny et al., 2022.)

The results of qualitative research are typically presented through rich descriptions, quotes, and narratives that capture the essence of the participants’ experiences. An example of a simple qualitative research study may be “the effect of having a designated nursing preceptor on the perceived satisfaction of new nurses.” Qualitative research in nursing enables a deeper understanding of the subjective aspects of health care, such as patients’ lived experiences, cultural beliefs, and social interactions. It explores the complexities and context in which healthcare phenomena occur, allowing for the exploration of multiple perspectives and uncovering novel insights. It also helps generate hypotheses and inform the development of quantitative research studies.

Understanding the Parts of a Research Article

Understanding the parts of an article is crucial for interpreting and extracting valuable information from scholarly literature. Each section of the article serves a specific purpose and provides essential insights for critical appraisal (Carey et al., 2020). Here’s a step-by-step look at how to interpret and analyze each component:

  1. Abstract: The abstract serves as a concise summary of the entire article. Pay attention to the research question, key findings, and implications. It provides a quick overview of the study’s relevance and helps determine if the article aligns with your information needs.
  2. Introduction: The introduction sets the stage for the research. Evaluate the background information provided and the clarity of the research question. Consider how well the authors justify the need for the study and their ability to connect it with existing literature.
  3. Methods: Scrutinize the methods section to understand how the study was conducted. Assess the appropriateness of the study design, sample size, data collection methods, and statistical analyses. This section should provide sufficient details to allow for replication and assess the validity of the findings.
  4. Results: Thoroughly analyze the results section to grasp the main findings. Examine any statistical analyses, figures, or qualitative descriptions presented. Consider the clarity of the results and the extent to which they support the research question. Assess whether the data analysis methods are appropriate and the results are accurately reported.
  5. Discussion: The discussion section is where authors interpret the findings and relate them to existing knowledge. Evaluate the authors’ ability to critically analyze the results, address any limitations, and consider alternative explanations. Look for implications for nursing practice, education, or future research that are supported by the findings.
  6. Conclusion: The conclusion summarizes the main points of the study. Assess whether the conclusions align with the results and discussion. Consider the authors’ ability to synthesize the findings and provide a concise summary of the study’s contributions.
  7. References: Review the reference list to identify the sources cited in the article. Assess the credibility and relevance of the references to determine if the authors have relied on reputable sources to support their claims.

Translating Research into Practice

Translating research findings to clinical nursing practice is a crucial process that involves applying evidence-based knowledge to improve patient care and outcomes It begins with critically appraising the research to assess its quality and validity (Titler, 2018). Nurses then consider the relevance and generalizability of the findings to their specific patient population and clinical setting. By integrating research findings with their clinical expertise, nurses can develop strategies for implementation, such as creating guidelines or protocols. Ongoing evaluation and monitoring of the implemented practices help nurses assess their impact on patient outcomes. Lifelong learning and staying up to date with current research ensure nurses remain informed and continue to enhance the quality of care they provide.

Steps of Evidence-Based Practice

Evidence-based practice (EBP) refers to the integration of the best available research evidence, clinical expertise, and patient preferences or values to guide healthcare decision-making and improve patient outcomes (ANA, 2023). According to the ANA, there are five key steps in implementing EBP: ask a clinical question, acquire the evidence, appraise the evidence, apply the evidence, and assess outcomes.

Ask a Clinical Question

The first step in implementing EBP is to formulate clear and focused clinical questions that address specific patient care issues. By framing questions in this format, nurses can identify the specific information needed to guide their practice.

Acquire the Evidence

Once the clinical questions are defined, nurses conduct a thorough search for the best available evidence to answer those questions. This involves accessing reputable databases, journals, and other reliable sources to find relevant research studies, systematic reviews, or clinical guidelines that address the identified clinical issues.

Appraise the Evidence

In this step, nurses critically appraise the quality and validity of the evidence gathered. They assess the methodology, study design, sample size, data analysis, and overall strength of the research. They decide if the information is applicable to the patient. This critical appraisal helps determine the credibility and applicability of the evidence to the clinical context.

When you have gathered all of the necessary evidence, the next step is to evaluate it for quality and validity. But how do you know what evidence is strongest and most applicable to your clinical question?

In the steps of EBP, the hierarchy of evidence refers to a ranking system that classifies different types of research studies based on their reliability and validity. The hierarchy helps healthcare professionals determine the strength and quality of evidence when making clinical decisions. The commonly recognized hierarchy includes systematic reviews and meta-analyses at the top, followed by randomized controlled trials (RCTs), cohort studies, case-control studies, cross-sectional studies, case series, and expert opinions at the bottom. The hierarchy of evidence serves as a guide, with studies higher up being considered more rigorous and providing stronger evidence to inform healthcare practices (Figure 1.9).

Diagram showing pyramid of different types of research designs; Bottom level: Background information and expert opinion; Rest of pyramid labeled Searchable via databases; Second through fourth levels from bottom labeled Unfiltered information: Case-controlled studies; case series and reports, Cohort studies, Randomized controlled trials; Fifth through eigth levels labled Filtered information: Critically appraised individual articles, Critically appraised topics, Systematic reviews, Meta-analyses.
Figure 1.9 The pyramid shows the quality of different types of research designs. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)

Nursing and other healthcare professions also frequently use Melnyk and Fineout-Overholt’s levels of evidence (Figure 1.10). Instead of a hierarchy, Melnyk and Fineout-Overholt list seven levels of evidence based on their methodological quality (2023).

Diagram showing pyramid of Melnyk and Fineout-Overholt’s levels of evidence. From bottom to top: Level VII: Evidence from expert opinions; Level VI: Evidence from a single descriptive qualitative study; Level V: Evidence from systematic reviews of descriptive or qualitative studies; Level IV: Evidence from a well-designed case-control or cohort study; Level III: Evidence from well-designed control trials with no randomization; Level II: Evidence from one or more well-designed RCTs; Level I: Evidence from a systematic review or meta-analysis of all relevant randomized controlled trials (RCTs).
Figure 1.10 It is important to note that the position of a study lower on the levels or hierarchy of evidence does not inherently imply a lower strength of recommendation; when evidence from lower levels aligns consistently across studies or is highly persuasive, strong recommendations may still be drawn. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)

Apply the Evidence

The next step involves implementing evidence-based interventions or changes in practice based on nursing knowledge and new expertise. Nurses integrate the findings from the new evidence with their clinical expertise and knowledge of individual patient values and preferences. They consider factors such as patient preferences, available resources, and feasibility of implementation when making decisions about patient care.

Assess Outcomes

The final stage of implementing evidence-based practices involves evaluating their impact on patient outcomes. Nurses collect data, monitor outcomes, and assess the effectiveness of the implemented interventions. This can help determine if the treatment will be effective for other patients as well. This ongoing evaluation helps identify areas for improvement and supports the continuous cycle of EBP implementation.

Clinical Safety and Procedures (QSEN)

QSEN Competency: Evidence-Based Practice (EBP)

Definition: Provide optimal patient care while integrating best current evidence and expertise with patient/family values and preference.

Knowledge: The nurse will describe reliable sources for locating clinical practice guidelines and evidence, and describe how the strength of evidence influences patient care.

Skill: Provide patient-centered care utilizing current evidence. The nurse will:

  • Create individualized care plans based on EBP and patient values.
  • Examine evidence reports and research relative to area of expertise.
  • Locate evidence related to clinical practice guidelines and topics.
  • Engage in the integration of new EBP in the work environment.
  • Consult with experts before deviating from EBP.

Attitude: The nurse will recognize the importance of reading professional journals and improving patient care based on new evidence.


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