Why, When, Who, What, How, and Where for Trainees Writing Literature Review Articles

Abstract

Literature review articles provide a valuable mechanism for remaining informed amidst an ever-increasing body of scientific work. Condensing current advances into this disseminatable form is a critical activity for any research trainee. To systematize this multifaceted process, we present the “why, when, who, what, how, and where” of composing a literature review article. Commentaries include selection of a review topic, conducting modern literature searches using online databases, stepwise strategies for manuscript drafting, and prevention of plagiarism. The current work provides structures and guidance for this fundamental effort which can establish the basis for a trainee’s development of original research objectives.

Why: Motivation for a Literature Review

Today’s researchers enjoy the ease of accessibility and searchability of scientific articles featured in online journal databases. However, with this convenience comes a great burden of expectation to remain updated on the incessantly growing body of work in one’s field.¹ While such a quantity of scientific developments continues to be produced and shared, it is a valuable and necessary exercise to communicate about combinations of these findings, in order to understand what has been revealed in the past, what is being explored currently, and what can and should be pursued next.

It is therefore highly beneficial for the scientific community to receive compilations of published work in the form of review articles. In an academic setting, reading review articles is often the first step of a new trainee’s initiative to learn about their research topic, and this exercise also provides the current impression of a field for seasoned principal investigators or for those venturing into new scientific territory.

Commonly, trainees are the executors of literature reviews and contributing authors of the resulting manuscripts. In addition to providing these valuable resources for the community, the process of inspecting and organizing the contributions of previous work yields substantial direct benefits for research trainees. In this article, we consider “why” writing a review article is a valuable exercise for trainees, as well as different phases during research training “when” it is worthwhile to write a review article. We also discuss with “whom” the process of conducting and composing a literature review can be shared, and the selection of “what” topic this process should address. We then examine “how” to approach writing a review article, and suggestions for “where” to publish the resulting work. These concepts and associated writing tools are summarized in Figure 1 and Table 1. While some of the following content is directed towards the goals of graduate students, much of the substance can potentially be useful for postdoctoral fellows, undergraduate students, clinical trainees, and other potential review article authors as well.

Figure 1.

Summary of considerations for trainees writing literature review articles.

Table 1.

Key concepts and writing tools involved while writing literature review articles.

Question Addressed	Concept Summary	Writing Tools
Why	Knowledge development	Vocabulary cultivation
	Experimental insight	Scientific writing structure
When	Early research trainees	State-of-the-art familiarity
	Advanced research trainees	Graduate degree milestone preparation
Who	Trainee co-authors	Collaboration and sharing feedback
	Faculty advisor	Determination of authorship
What	Topic and scope clarification	Previously published review articles
	Content style and meta-analysis
How	Online database searches	Database search functions
	Article and information organization	Spreadsheet
	Initial survey of abstracts	Draft skeleton
	Stepwise drafting	First draft phrases
	Editing with integrity	Citation and plagiarism screening software
		Research librarians
Where	Invited reviews	Suggested or self-generated topic sources
	Review journals

Why: Context for the Research Project

The process of writing review articles can establish a meaningful context for a trainee’s research initiatives, such as a graduate student’s thesis. This exercise first requires performing a historical survey of progress already made on the topic. Reading about prior studies may prompt trainees to ask further questions that can lead to the development of unique research objectives. This effort also allows contemplation of the importance of one’s research, and thus facilitates the definition of intentions for one’s work.

Reviewing the body of literature also confers familiarity with the language of a specialized field. For instance, surveying related works by various authors can reveal different versions of communicating about the topic, and the trainee may gain understanding as to which version is most clear. This experience of learning and clarifying vocabulary serves as foundation for the background and discussion of future primary articles and for a graduate student’s qualifying exam and thesis defense. In addition to individual words, the overall style of a scientific article may be new to a trainee author, and composing a review article can help a trainee to transition from the expository writing form of previous educational stages.² Such benefits may also be expanded to students enrolled in graduate or undergraduate seminars which employ review article-like assignments and provide instruction on the message and structure of scientific writing.^2,3

Additionally, from the standpoint of professional advancement, reviews on emerging topics exhibit high visibility and are often cited by the introductory sections of primary research articles, thus introducing one’s scientific presence in the community. With expanding use of keyword-based electronic digests, one can also potentially begin to garner name recognition from other researchers in the field of one’s topic.

When: A Different Purpose for Any Phase

During a trainee’s beginning research efforts, writing a review article can allow one to become immediately, extensively familiar with one’s research topic. The task is also suitable for later in training, once related procedures have been explored in the laboratory. This practical context fosters the trainee’s ability to generate and judge the validity of new research questions, while identifying applicable methodologies for such pursuits during the literature survey.

Graduate students approaching their qualifying exams can use knowledge collected from writing review articles to prepare background for their written proposals and oral assessments. Meanwhile, advanced graduate students can use the opportunity to acquire a final up-to-date context for their body of work as they compose their theses and present their defenses. Students who write review articles earlier in training can even compose an additional article later with updates from studies during the intervening years, and this series of publications can conveniently serve as introductory chapters for their written theses.

Who: Partnership and Mentorship

Some trainees write reviews without the assistance of another trainee; others form groups and research different sub-topics. As in the latter situation, it is generally advisable to have a co-author with whom one can divide the considerable workload that writing review articles entails. This partnership can feature establishing deadlines for different parts of the composition and holding each other accountable for these tasks. Like in any team for whom the distribution of credit for the work is critical to professional advancement, it is preferable to establish as early as possible how the authorship credit will be shared, such as co-first-authorship and the order of author’s names. Towards the purpose of scientific integrity, whether the roles of those who participate in various stages of the literature review process should constitute authorship must also be ensured. For example, a fellow trainee who receives a fully drafted version of the manuscript and provides commentary on the writing might be considered as a candidate for acknowledgement rather than a co-author.⁴ This determination may also be made according to the authorship definition and policies of the expected journal of submission.

Meanwhile, one’s thesis advisor serves as an essential instructor for the quality and accuracy of the manuscript. Feedback can be obtained upon sharing a description of one’s selected articles or the spreadsheet and draft skeleton described below, as well as periodic opportunities for the advisor to skim the overall structure of the paper.

What: Narrowing the Topic

Once the team is assembled, the next critical task consists of clarifying the article topic. For example, during the literature survey, the review paper topic may transform from an initial broad range of subjects to a specific subset, while still including the most pressing considerations in the field. If one’s research will involve an established grant, a useful approach is to read the grant’s referenced articles. Trainees can also delve into publications in areas related to the potential topic from members of their own labs.

A key activity is performing a survey of existing reviews, in order to familiarize oneself with their structure and to accrue ideas for relevant topics to address. Most crucially, this exercise will aid the authors in establishing the gap into which their review paper can contribute. To impact the larger scientific community meaningfully, the new article should be distinguished from existing reviews, especially those recently conducted within the past few years. As a possible approach, the authors could note within a broad previously published review article that a particular topic is discussed in a section of no more than a few paragraphs. They may then proceed to develop this truncated subject into its own review article by delving into greater detail of the background and significance of the studies listed in the previous review, and by combining this discussion with additional studies such as those originating from other disciplines. The authors may even begin their literature survey by reading articles cited in the earlier review publication, yet it is essential to cite this prior review given its substantial influence on the new article’s content. Authors should therefore define for themselves and the readers the specific questions that this new article intends to explore, relative to the goals and contributions of previous reviews.⁵

Through these starting efforts, one can decide the review article’s scope, designating what to include and noting what will be excluded. These boundaries should be clarified both to guide the trainee’s next tasks, and also explicitly in the introduction of the article’s text for the reader’s understanding. The range of years during which included articles were published can additionally provide the reader with an appreciation for the age of the field and the timely nature of the review article.⁵

What: Applications and Style

The specificity of one’s topic may depend on the extent of its history—broader for a very new topic if not much work has yet been done, in contrast to a targeted area in a well-established field. Commonly, one must decide on the range of content to include. For example, a trainee whose research group explores certain applications may choose to focus on the expertise areas of the lab, or extend beyond to include other areas in that field.

Another decision influencing the overall nature of the review article is the style of presentation for the primary articles. One should judge between these options by reading the literature of the topic and deciding which style is most fitting for the information necessary to convey, as well as by considering the particular requirements and example publications from the targeted journal for the publication.

Style I: Description of different studies, preceded by the goal of the illustrated concept and followed by significance

From this review style, researchers can learn about the variety of methodologies available for their intended application, and can gain deepened understanding of content discussed by learning of specific research findings that illustrate the concepts. However, readers may seek to skim through these details if they are not relevant to their interests or experiences.

Style II: Summarized, integrated discussion of concepts

This second option can be chosen with the assumption that readers who would want to learn more details or replicate the study will examine the source directly. Otherwise, for readers seeking a broad conceptual overview, this style can be more efficient for arranging the discussion. One can present succinct information on the main messages of a study’s findings in the context of other points being made, while providing readers with the citation if more information is needed. Meanwhile, the trainee authors can record the more specific details for their own benefit using a spreadsheet to organize the knowledge, as will be discussed later in this work.

For either style, original study findings can be conveyed both conceptually and through numerical expressions of the range of demonstrated values. From this content, both the readers and the trainee author can derive a guideline for choosing methodologies or anticipating outcomes.⁵ When performing such meta-analysis, it is especially important to dictate and state the methods of acquiring the included articles, particularly to ensure that multiple authors are employing consistent practices for literature searches. Statistical techniques for quantitatively synthesizing data from different studies should also be carefully chosen and described.

How: Database Searches and Organizational Tools

Once the subject of the literature review is established, a series of actions can be conducted to yield a publishable manuscript. Essential tools for these efforts for the modern trainee include the online journal databases to which one’s institution subscribes, such as PubMed^®, Web of Science^™, and Scopus^®.⁶ Google Scholar^™ can also be used for targeted concepts, such as when seeking a citation for general knowledge in the background section.⁶ A necessary practice is the determination and recording of search terms used, and the listing of these terms in the introduction of the review article. In these electronic systems, one may take advantage of advanced search features such as employing Boolean operators—”AND”, “OR”, “NOT”—to appropriately narrow one’s search.⁷ The trainee can also create a digital collection of search results for later consultation using functions like the Marked List in Web of Science.

As an organizational tool, one can create a spreadsheet for recording article names and the key characteristics of the work from the methods and results sections. The particular characteristics of interest will be determined by the review article topic, and further tailored as one’s review topic is progressively refined throughout the writing process. For instance, the intention to compile information on certain techniques can be elaborated to include the equipment model, usage parameters, and associated processing methods.

In addition to providing an effective organizational tool for the current effort of writing a review article, this spreadsheet can serve as a valuable personal resource for the trainee’s future scientific endeavors, as one can easily consult these summaries of precedent work to guide one’s own experimental plans and understanding of the current state of the field. Once assembled, the trainee can even continue to update this spreadsheet with new entries after the current review article is finalized, as an efficient mechanism for maintaining and processing the latest knowledge about one’s thesis topic. Furthermore, this spreadsheet can be adapted into one or multiple tables for the review article, in order to provide a comprehensive summary of the work in the field, which may serve as a resource of information beneficial to the readers planning their own initiatives based on these precedents.

While the articles’ content can be organized using the described spreadsheet, the downloaded files of the articles themselves should also be gathered in a systematic manner to allow ease of repeated access during the writing process. The trainee may establish a literature library using a literature collection program such as Papers or Mendeley^®, or by a thoughtful labeling system in one’s own computer files. Additionally, a citation software such as EndNote® or Zotero’ is beneficial for writing any manuscript such that reference numbers are automatically reordered upon the addition of a new source, and these tools are especially indispensable for the modern undertaking of writing review articles.

Decisions about and access to these various systems can be crucially facilitated by research librarians associated with the authors’ institution. These information science specialists provide customized guidance on approaching the literature and managing the yielded material.⁸

How: Literature Survey and Draft Skeleton

With these tools established, one next proceeds to conducting a survey of the literature yielded from the chosen search terms. The trainee’s first pass should consist of reading the abstracts and examining the figures of the papers. One can begin to designate these papers as “first-, second-, or third-priority” based on their degree of relevance to the chosen review topic as well as a preliminary assessment of their importance to the field. For beginning researchers, the number of citations and journal impact factor may assist with this judgment.

After performing this survey for at least the first few pages of search results, and after discussing one’s general impressions of the review article’s expected scope and goals with the co-authors and research advisor, composing a “draft skeleton” can facilitate the trainee’s selections of key features of the review article, such as:

• The topic, audience, and type of review⁹

• Search criteria for literature databases

• Potential title for the article

• Initial abstract of the article

• Outline of sections with two to four subtopics

This type of document can also be created for other writings such as primary research articles.

How: Begin the Draft

To begin the initial draft, the trainee may choose five to ten first-priority papers from the survey of article abstracts. As a strategy available for any writing application which is particularly useful for review articles, one can take the approach of quickly—even incompletely—noting one’s cursory ideas for content first. Such starting text may consist of phrases representing the most important points from the article’s abstract, with the expectation that these thoughts will be reorganized and synthesized into full sentences with added transitions at a later time, according to the chosen paper style. For Style I, these initial concepts may include details of the methodology and results, or for Style II, the phrases may encompass the “take-home” message of the work. If the trainee wishes to record this foundational material at an accelerated pace, one may add direct quotations—with care to mark them for later replacement, such as by coloring the text—in order to incorporate the content temporarily into the draft.

Next, one can categorize themes from the literature to build the structure of the review. For example, there may be a few crucial challenges to overcome or discoveries to make in order to enable the next generation of advances for the field. After forming these categories and considering the topics in one’s draft skeleton, section headings can be introduced into the draft document, which the author can use to navigate the article as content is added from each reviewed primary manuscript. As these categories expand and mature, one can repeatedly return to and update the draft skeleton and abstract.

How: Expansion of the Draft

Building from this foundation, the trainee can then fully read and annotate the primary publications according to the established criteria of the chosen topic. One may find it helpful to print and physically write on the compositions, or it may better suit one’s organizational style to use electronic versions. In either format, the trainee can annotate the document by writing about notable findings in the margins, or by color-coding the content according to the anticipated sub-topic category within the review.

After the five to ten first-priority papers have been added in this manner and have established the structure of the review, one can identify and incorporate second- and third-priority papers. Once the range of content to discuss from the reviewed articles has been thus elucidated, one can add general information into each sub-topic’s section. To write the introductory section, one can retrace each interpretation of articles in the body and compose a corresponding background explanation of substance the reader would need to understand. As each layer of information is added, one can preserve the draft version by saving it with a file name containing the draft’s number and description (e.g. “v1 Phrases”).

How: Editing and Finalizing the Draft

The editing stage of writing a review article presents a special challenge to concerns of scientific integrity. The trainee must apply caution while weaving the original authors’ ideas into the review article’s narrative, by ensuring that the authors’ words and writing style have been sufficiently changed while maintaining accuracy of the concept’s presentation. This task may be difficult because the original author’s language may already be in its most succinct and comprehensive form. One must be aware and self-suspicious of unknowingly using the source’s language. For example, the trainee might have written a paraphrased interpretation into the initial draft using one’s own language, then independently reworded the content during editing of a later draft. However, it is possible to change the content back to its original language inadvertently. This highly important concern is easy to breach accidentally. Therefore, the trainee must frequently re-check the source article to compare the writing expressions, such as by using “find” functions to check for an exact word in the original manuscript’s electronic document. For particularly lengthy review articles, software such as iThenticate^® or Unicheck^™ can be used to verify the integrity of one’s editing process and resulting article content.^10,11

At this stage of completion, the trainee can also consider possible relevant figures to include, such as the number of papers published on the topic per year to show trends of increasing importance. After long periods of exchanging feedback with one’s co-authors and advisor, the trainee may need to repeat the literature search using the recorded search terms. Such an update may also be necessary during the reviewing process undergone with the chosen journal for submission.

How: Maximizing the Benefit

In addition to the value the review article will feasibly provide to the community, there are simple actions a trainee can perform to maximize the personal benefit from the review writing process. For instance, one may compile any ideas that arise for one’s own future work while reading the seminal articles in the field. A trainee may also find it worthwhile to keep a record of reviewed methodologies such as internal methods of validation which one can include to strengthen experimental planning and subsequent primary manuscript content. These notions of future work or ubiquitous laboratory approaches can be discussed in the conclusion of the present review article, while also being incorporated into one’s personal plans for research endeavors.

Surveying the literature of one’s thesis topic also provides the opportunity for the trainee to become familiar with the corresponding authors and institutions which constitute the prominent groups in the field. This understanding can be acquired by including the first and corresponding authors of the tabulated publications in the spreadsheet.

Where: Publication Opportunities

Invited reviews offered to one’s thesis advisor constitute opportunities for undergoing and composing a literature review, often with some preliminary direction of the review article’s topic. Meanwhile, specific journals for review articles are available in many different fields when seeking publication for a self-generated topic.

Conclusions

Facing a multitude of articles a trainee must survey in order to conduct a literature review, the process of performing and composing a literature review can be approached in a methodical manner. Most importantly, these strategies can address the challenge of organizing these findings into an effective form for others’ usage. This standard task within research training can be undertaken to yield maximum value and benefit for the trainee and the community whose work the manuscript will summarize, reflect upon, justify, and enlighten.