A narrative review is considered a non-systematic review that has the author analyzing available literature on a topic of interest. Because the nature of a narrative review, there are no standard guidelines on how to conduct one, unlike a systematic review. This is also typically a format of review that is done by students. 

The components of a narrative review

There are several steps to formulating a question for a narrative review. These steps consist of setting the scope of the review and assessing how you will approach your research.

Setting the Scope

This step consists of helping the patron take themselves from a broad topic to a narrower topic. In traditional narrative reviews, a topic should be narrow enough to to have a focus, but broad enough to incorporate different research approaches and methods. 

When helping to narrow down the topic, you can start with having the patron list out subtopics of the general topic they're interested in and choosing one or two that hold their interest and relate to one another. You should also try to have them set operational variables, meaning the population they're focusing on. Significance of their topic to theory, policy, practice, and action are important to consider, as that will guide the purpose of their writing. 

You may also find that mind mapping can help sharpen your question, as well as produce some keywords to start a basic search. The University of Arizona has a Mind Mapping activity that you can use to help create a focus to your research question.

Approach to Research

There are several ways to frame a question, based upon the type of research the patron will be searching for. These methods are:

• Quantitative questions, which focus on measuring outcomes, statistics, and variables. These types of questions are commonly formatted when you want to assess the outcomes of a practice, and will focus on finding datasets.
• Qualitative questions, which are open ended questions that emphasize processes and experiences of certain groups, and will focus on finding studies with qualitative data.
• Mixed method questions, which allows you to combine questions that focus on measurable outcomes as well as personal experiences.

Narrative reviews typically use either qualitative or mixed method question formats. It's also acceptable and expected for your patron's research question to evolve and be refined as they research. It's also recommended to include the criteria for the search with the research question, though it is not always required.

Keyword Searching

If a patron is struggling to come up with keywords for their search, organizing and visualizing keywords can help create a launch point for the search strategy. Some questions to ask the patron to guide them are:

• What are the important parts of your topic?
• What documents/materials do you need? 
• What language is being used in the research? Is there engineering jargon, medical terminology?

Conducting a basic preliminary search of the most recent research can also help to gather keywords and scope what terminology is currently being used. From here, you should introduce Boolean Logic to combine the search terms, as illustrated in Section 2. 

Thesauri

Many databases have a thesaurus you can use to help generate synonyms and search terms related to your topic. Some examples are Engineering Village and PubMed's MeSH Database. It's good to use these thesauri to help generate keywords if you're struggling to find those that are related to your research.

Documenting the Search

An important step to the search strategy is determining how one will document their search process. This goes beyond just saving citations, but also documenting what search strings are used, and where. This is great for a patron to take note of because it can help them retrace their steps when trying to find a source.

The Search as an Iterative Process

A narrative review's search evolves as the search process advances. The best search method is to start broadly with tertiary sources the patron's desired topic to gain some familiarity with the topic as a whole, with a preliminary search of the literature. This will then help inform searching for secondary and primary sources. Additionally, a narrative review's search should always be evolving and informed by the sources found, as they can help identify where gaps in your search strategy exist.

Scope

When writing a narrative review, it's important to be able to be able to set out a scope of what you're researching. There are two types of scopes to consider in a typical narrative review:

• Representative Review is done when you're selecting sources based upon what's considered representative to particular groups of the literature.
• Central Review: is done when you want to select sources that are influential to your topic.

Aside from determining the scope of literature you'll review, like a systematic review you will also need to determine your other inclusion and exclusion criteria. Some criteria you may want to consider are it's relevancy, including sources outside of your discipline; supplying context for your research; authority voices on the topic; and relation to your discipline.

However, like other forms of review, you should consider how publication bias may impact your selection criteria and process. 

Citation Managers

Citations managers are great ways to organize the information you have gathered during your research. Some citation managers we typically recommend include:

• Zotero: an open source citation manager that is free to use. It's designed to help users collect, organize, cite, and share research materials. It is able to integrate with word processors as well as supports PDF management.
• Mendely: an open source citation manager that allows researchers to collect, organize, cite, and share citation sources. It struggles with PDF management. 
• EndNote: a citation manager that allows researchers to collect, organize, cite and share their citations sources. This manager does cost money. 

Note Taking

One method to ensure efficient note taking when reading articles is the ANTICs (article note-taking index cards) method. This method highlights prominent issues related to your topic, and has you reflect in your own words the source.

The ANTICs method, as shown by Efron and Ravid in Writing the Literature Review, consists of using a flashcard to create a section for the information of the source, such as it's authors, title, year of publication, and research question. Then you will delve into the issues that the source discusses and relates to your topic, and your thoughts on what is discussed. This then culminates into a discussion of the overall issues. 

You should also consider mapping the themes of the literature you're reviewing, as this will aid in finding commonalities during the synthesis of the information. This can be done concentrically, through starting with your main topic in the center and expanding upon with rings of "themes", or through mind mapping.

A typical narrative review will focus on qualitative studies. When it comes to beginning the process of synthesizing such information, a good rule of thumb is to try and group your sources into themes, such as research methodologies, issues within the literature, or points of view. This can help create a bigger picture on how the information gathered flows together, and can lead into synthesizing the information in different ways.

One such way could be comparing and contrasting the information. This is typically done through a Venn Diagram, and is helpful when trying to determine of the information in different sources interact with one another. 

With the information presented in such a manner, a patron may be tempted to look for patterns that compliment each other, However, it's important to note any conflicting information. Particularly in a narrative review, such information reflects the rigor of the study done, and can shed light on new information or nuance of the topic. From there, you should take a critical stance on the information presented with clear explanation in your reasoning, which is done through a close reading of the texts. 

A quantitative narrative review's synthesis will focus the type of studies observed, their participants, the intervention, the outcomes, and critical analysis of the quality of each study. You should also highlight the observed patterns and trends of the studies, and then synthesize the information found in all of the studies. Ask yourself, what does this data mean together?

Mixed method narrative reviews either have the qualitative and quantitative studies reviewed in two halves and then synthesized together in the end, or sequentially, with the qualitative synthesis informing the quantitative synthesis, and occasionally the quantitative search.

1. Mind Mapping by Arizona State University
2. Narrative Reviews: Flexible, Rigorous, and Practical (Sukhera)
3. An Introduction to Writing Narrative and Systematic Reviews (Greggory, Denniss)