Introduction – Finding and Appraising Literature
Learning Objectives
By the end of this section, you will be able to:
- Explain the purpose and importance of a literature review in research.
- Locate and evaluate primary and secondary research.
- Describe different types of literature reviews and their uses in nursing research.
- Conduct an effective literature search using relevant databases and search strategies.
- Identify research gaps, contradictions, and key themes in nursing literature.
- Understand how literature reviews inform PICOT questions and study design
- Begin building your own literature review with confidence and academic rigour
Welcome to Chapter 6: Finding and Appraising Literature
Every nursing research study builds upon the work of others. Before researchers collect data, recruit participants, or analyze results, they first need to understand what is already known about their topic. This process begins with a literature review.
A literature review is much more than searching for articles or summarizing studies. It is a critical and systematic exploration of existing knowledge that helps researchers understand what has already been discovered, identify where evidence is strong or weak, recognize contradictions, and uncover gaps that require further investigation. In nursing, literature reviews are essential for ensuring that new research builds on existing evidence rather than unnecessarily repeating work that has already been completed.
Throughout this course, you have been learning how researchers think. In Chapter 4, you explored how the research process unfolds from beginning to end. In Chapter 5, you learned how meaningful research questions emerge from knowledge gaps. This chapter builds directly on those ideas by asking an important question:
How do researchers know what is already known, and how do they discover what still needs to be studied?
Developing strong literature searching and critical appraisal skills is fundamental to evidence-informed nursing practice. Whether you are completing an undergraduate assignment, participating on a research team, or pursuing graduate studies, the ability to locate, evaluate, and synthesize evidence allows you to make informed clinical decisions and contribute to improvements in patient care.
In this chapter, you will learn how to search nursing databases effectively, distinguish between primary and secondary research, critically appraise the quality of evidence, and understand the different families of literature reviews used in health research. You will also learn practical strategies for organizing your search, refining your research question, and writing a literature review that synthesizes evidence rather than simply describing individual studies.
Like every chapter in this textbook, remember that research is not a series of isolated steps. Each stage builds upon the previous one. A thoughtful literature review strengthens your research question, guides your study design, and ultimately helps produce research that advances nursing knowledge and improves health outcomes.
Where are we in the research journey?
· Chapter 1: Why does nursing need research?
· Chapter 2: Understanding knowledge and ways of knowing.
· Chapter 3: Conducting research ethically and respectfully.
· Chapter 4: Understanding how a research study unfolds.
· Chapter 5: Developing meaningful research questions.
· Chapter 6: Discovering what is already known through the literature.
Key Definitions for becoming an evidence-informed nurse
Boolean Operators: Search commands (AND, OR, NOT) used to broaden or narrow database searches.
Critical Appraisal: The systematic evaluation of research to determine its quality, credibility, relevance, and applicability.
Grey Literature: Research and information produced outside traditional academic publishing, including government reports, policy documents, theses, conference proceedings, and organizational reports.
Keyword: A word or phrase used to search for literature related to a research topic.
Literature Review: A critical synthesis of published evidence that summarizes what is known, identifies gaps, and provides context for a research question.
Meta-analysis: A statistical technique that combines quantitative findings from multiple studies to estimate an overall effect.
Meta-synthesis: A method of integrating findings from multiple qualitative studies to develop new interpretations or understandings.
Narrative Review: A broad summary and discussion of literature on a topic without using a formal systematic review process.
Primary Literature: Original research studies reporting firsthand findings collected and analyzed by researchers.
PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analyses; an internationally recognized guideline that promotes transparent reporting of systematic reviews.
Research Gap: An area where insufficient, inconsistent, or unanswered evidence exists, indicating a need for further investigation.
Scoping Review: A type of literature review used to map the breadth of evidence available on a topic and identify knowledge gaps.
Secondary Literature: Publications that summarize, synthesize, or interpret findings from primary research, such as systematic reviews and clinical practice guidelines.
Systematic Review: A rigorous, transparent, and reproducible review that identifies, critically appraises, and synthesizes all relevant research addressing a focused question.
Synthesis: The process of integrating findings from multiple studies to identify common themes, patterns, relationships, and gaps in the evidence.
Discovering What is Already Known Through the Literature
A strong research project begins with a solid understanding of what is already known—and what still needs to be explored. In nursing research, the ability to locate, evaluate, and synthesize high-quality literature is essential for building evidence-informed practice, supporting clinical decision-making, and identifying gaps that can strengthen patient care across health settings.
For example, as a nursing student, learning to navigate scientific literature will not only support your coursework and undergraduate research opportunities—such as the TRU UREAP Award (https://www.tru.ca/research/undergraduate-research/undergraduate-research-opportunities/ureap-award.html)—but also prepare you for future roles in clinical inquiry, leadership, and graduate study.
In this chapter, you will learn to:
- distinguish between primary and secondary research literature
- conduct efficient searches using nursing databases such as CINHAL, PubMed, Scopus, and Web of Science
- understand the major families of literature reviews
- critically appraise research evidence; and
- organize and synthesize literature to support a research question
You will also be introduced to practical search strategies using TRU library resources, Google Scholar, keyword development, and evidence frameworks commonly used in nursing scholarship.
Developing strong literature-searching and critical appraisal skills is foundational to becoming an evidence-informed nurse. These skills will support your success throughout your nursing education and future professional practice.
Research Tip: Refining Your Literature Search
Effective literature searching is an important part of the nursing research process. As discussed in Chapter 4, research librarians can help students and researchers:
- develop search strategies
- identify appropriate databases
- refine keywords and subject headings
- improve search efficiency and accuracy
One common strategy used in database searching is Boolean searching, which combines keywords to narrow or broaden results.
Common Boolean Operators
| Operator | Purpose | Example |
| AND | Narrows the search by combining concepts | nursing AND chronic pain |
| OR | Broadens the search by including similar terms | Adolescents OR teenagers |
| NOT | Excludes unwanted terms | Cannabis NOT recreational |
Example Search String:
(“medical cannabis” OR cannabinoids) AND chronic pain AND nursing
Developing effective search strategies takes practice. Research librarians are valuable partners in helping nurses locate high-quality evidence efficiently and systematically.
References
- Intellectual property of Dr. Florriann Fehr/TRU Open Press CC BY-NC-SA 4.0
Search commands (AND, OR, NOT) used to broaden or narrow database searches.
The process of carefully examining a research study to determine whether its methods and findings are trustworthy and useful
Research and information produced outside traditional academic publishing, including government reports, policy documents, theses, conference proceedings, and organizational reports.
A word or phrase used to search for literature related to a research topic.
A review of published research used to identify what is known, what is not known, and how a study fits within existing knowledge.
A statistical technique that combines quantitative findings from multiple studies to estimate an overall effect.
A method of integrating findings from multiple qualitative studies to develop new interpretations or understandings.
A broad summary and discussion of literature on a topic without using a formal systematic review process.
Original research studies reporting firsthand findings collected and analyzed by researchers.
Preferred Reporting Items for Systematic Reviews and Meta-Analyses; an internationally recognized guideline that promotes transparent reporting of systematic reviews.
An area where insufficient, inconsistent, or unanswered evidence exists, indicating a need for further investigation.
A type of literature review used to map the breadth of evidence available on a topic and identify knowledge gaps.
Publications that summarize, synthesize, or interpret findings from primary research, such as systematic reviews and clinical practice guidelines.
A rigorous, transparent, and reproducible review that identifies, critically appraises, and synthesizes all relevant research addressing a focused question.
The process of integrating findings from multiple studies to identify common themes, patterns, relationships, and gaps in the evidence.