Research - Conducting a literature review: Nursing

Nurse Marin works in a cardiac catheterization lab. Last week, a client experienced a major bleed from the puncture site after leaving the cath lab. This is the third bleeding event in the past month. Nurse Robin, who also works in the lab, asks “I wonder if there is something we can do differently to prevent bleeding in this client population?” Nurse Marin agrees and proposes that the healthcare team begin a quality improvement study on how to prevent bleeding in the post-catheterization period. As a first step in this research study, Nurse Marin will perform a literature review to learn more about best practice in the post-catheterization client.

Literature is any written document like a newspaper, magazine, scientific journal, or book. A literature review is done when a researcher wants to compile all of the literature that currently exists on a topic to answer a research question or problem. This is sometimes called the ‘state of the science.” A literature review is often done as one of the first steps of a research study or it can be published alone as a summary of what is known about a topic.

Now, literature can be classified in a few different ways. First, you can categorize literature as either theoretical or empirical. Theoretical literature discusses the application of a theory to practice. Types of literature that fall into this category are theories and theoretical models. Nurse Marin finds a source that describes how the Theory of Self-Care could be applied in the post-catheterization period. Empirical literature, on the other hand, includes sources that use direct or indirect observation, like quantitative and qualitative research. Nurse Marin finds an example of empirical literature when she comes across a quantitative research study showing that clients on anticoagulants during pre-cardiac catheterization were more likely to have post-catheterization bleeding.

Next, literature sources are categorized as either primary or secondary. Primary literature is original research presented by the researchers, like an experimental study. Secondary literature is an interpretation or analysis of a primary source, like a meta analysis that reviews multiple studies to form a single conclusion. . One primary source Nurse Marin finds is a quantitative research study which measures the incidence of bleeding in clients who received heparin in the post-catheterization period. A secondary source that she found was a published literature review comparing risk of post-catheterization bleeding between five of the most commonly used anticoagulant medications.

When you’re getting started with your literature review, The Systems Model is a helpful tool to guide you through the process. In The Systems Model, there are three stages: input, throughput, and output.

During the input stage, you complete your literature search, which is an organized search to identify sources that are relevant to your topic. The highest quality research can be found in databases, which are collections of literature, typically grouped by discipline, like medicine or education. The Cumulative Index to Nursing and Allied Health Literature, called CINAHL, is a commonly used database with a nursing focus. When conducting a large literature search, you can use keywords related to your topic, but this could deliver an overwhelming number of sources. So, it’s useful to narrow down your search with Boolean operators which are words like “and”, “or”, and “not” that link keywords. The word “and” will get you a smaller number of search results since both of the keywords must be present. Using “or”, on the other hand, will increase your search results because either word could be present to show up in your results. Lastly, “not” will eliminate literature that you don’t want.

So, when Nurse Marin is conducting her literature search, she uses the keyword “cardiac catheterization” which generates over 10,000 results! As she skimms the results, she notices that some of the sources also use the key word “heart catheterization.” Nurse Marin doesn’t want to miss any of the relevant sources for her literature review so she utilizes the Boolean operator “or.” Now she searches for “cardiac catheterization OR heart catheterization” and gets 10,800 results. Nurse Marin sees that many of these sources do not even address bleeding so she changes her results to: cardiac catheterization OR heart catheterization AND bleeding. Now she is down to 1,000 results which are more closely related to her topic.

Another technique is to identify search filters. Filters are criteria you can set within an electronic search engine to eliminate sources that do not meet your criteria. Now Nurse Marin has 1,000 potential sources and that is still too many to sort through, so she decides to apply a search filter so that only literature from the past five years will appear in her search. This brings her number of sources down to 300.