The Literature Review

A literature review is a structured examination of everything that has been published on a particular topic, theory, or clinical question. The term “literature” refers to all relevant sources of information, including peer-reviewed journal articles, clinical guidelines, textbooks, and professional reports. A literature review helps nurses understand what is already known about a topic so they avoid repeating work unnecessarily, unless replication is needed to test accuracy, update findings, or examine a concept in a new population such as Indigenous communities, rural/remote settings, or Canadian health-care systems. A strong literature review does more than summarize sources. It critically analyzes and synthesizes evidence, identifies key themes, and provides a clear context for the research problem.

Purpose of a literature review

A literature review involves an in-depth examination of research articles, books, guidelines, and other scholarly material related to your research problem. This step clarifies whether your question has already been answered, how extensively the topic has been studied, and what methods other researchers have used.

More than a search for information, a literature review connects existing evidence to your topic. It helps you identify what is known, what remains unclear, and where gaps exist. This allows you to determine the contribution of each source and to evaluate the strength of the overall evidence base.

Regardless of the type of study you plan to conduct, the core purposes remain the same. A literature review allows you to:
• Provide context for your research problem
• Justify why your study is needed
• Confirm whether your proposed work has already been done
• Identify where your study fits into existing nursing knowledge
• Learn from previous theories and findings
• Recognize flaws or limitations in past research
• Highlight gaps requiring further investigation
• Clarify how your study will add to nursing knowledge
• Refine or redirect your research question as needed

Writing a Literature Review

Writing a literature review involves three main steps:

1. Research – Locating credible sources such as peer-reviewed nursing journals, clinical guidelines, dissertations, and academic books.

2. Critical Appraisal – Evaluating each source for rigour, credibility, methodology, and relevance to nursing practice.

3. Synthesis and Writing – Organizing and integrating the literature into a coherent narrative that supports your research question.

Many nursing students find it helpful to imagine the process as a funnel—starting with broad information and narrowing toward the most relevant studies.

A thorough understanding of the literature is essential for high-quality nursing research and evidence-based practice. Fink (2019) describes literature reviews as systematic, explicit, and reproducible processes for identifying, evaluating, and synthesizing existing work. Novice researchers should review published research critically and comprehensively to understand the topic and identify meaningful research gaps.

Types of Research Literature

Nursing research literature can be broadly categorized into primary and secondary sources, each playing a distinct role in the development of evidence-informed practice.

1. Primary Literature

Primary literature consists of original research studies that report firsthand findings from investigations conducted by researchers. These sources provide detailed descriptions of study design, methodology, data analysis, and results, allowing readers to critically evaluate the evidence.

Examples of primary literature include:

• Qualitative studies (e.g., interviews, focus groups) that explore experiences and perspectives
• Quantitative studies such as randomized controlled trials (RCTs), which test interventions under controlled conditions
• Observational studies, including cohort and case-control designs
• Case studies and case series that provide in-depth examination of individual or group clinical cases
• Theses and dissertations that present original academic research
• Conference abstracts that share preliminary or emerging findings
• Preprints, which are early versions of research articles shared prior to peer review

In Canada, common databases used to locate primary research literature include CINAHL, PubMed/MEDLINE, Embase, Emcare, Scopus, Web of Science, PsycINFO, and Google Scholar.

2. Secondary Literature

Secondary literature involves the synthesis, analysis, and interpretation of primary research studies. These sources are valuable for summarizing large bodies of evidence and identifying overall trends, strengths, and gaps in the literature. They are especially useful in supporting clinical decision-making and the development of best practices.

Examples of secondary literature include:

• Systematic reviews, which comprehensively collect and critically appraise relevant studies
• Meta-analyses, which use statistical techniques to combine results from multiple studies
• Meta-syntheses, which integrate findings from qualitative research
• Clinical practice guidelines, which provide evidence-based recommendations for care

Secondary literature can be accessed through many of the same databases used for primary research, including PubMed, CINAHL, PsycINFO, Scopus, and Web of Science.

Additional sources include:

• Search engines such as Google Scholar (use with caution, as results may vary in quality and relevance)
• Grey literature, such as government reports, policy documents, organizational publications, and dissertations, which may not be commercially published but can provide valuable insights

Tips for Effective Literature Searching

A structured and strategic approach to searching improves the quality and efficiency of literature retrieval:

• Use Boolean operators (AND, OR, NOT) to refine and combine search terms effectively
• Keep a record of search strategies, including keywords, databases, and results, to ensure transparency and reproducibility
• Review reference lists of key articles to identify additional relevant studies (a technique known as citation chaining)

Remixed from:

• An Introduction to Research Methods for Undergraduate Health Profession Students by Bunmi Malau-Aduli and Faith Alele (2023), published under a CC BY NC 4.0 license.
  • Chapter 2.5: Reviewing the Literature

Media Attributions

• Dr. Fehr [avatar] by Katie on Canva using Canva AI image creation https://www.canva.com/ai-assistant/
• Figure 6.1 Different types of literature reviews synthesize evidence in different ways is by Resarch Assistant Ime Stavinga and is subject to the CC BY-NC-SA 4.0 license.

References