How to review literature.

I have been teaching research methodology and statistics for some 15 years now and have a good feel for the issues that are usually problematic for new researchers, whether they are clinicians or students. Reviewing the literature is a common problem area. Novice researchers often hear the term used and nod wisely, assuming that the ability to do this effectively will (maybe by osmosis) emerge once they start to read. This does not happen. What does happen is that the pile of articles accumulated gets larger by the day and simply adds to the confusion and apparent enormity of the task.

Fear not, clarification is at hand! One of the main problems with reviewing literature arises as a result of not understanding how the research process works; hence, the real purpose of reviewing the literature is not abundantly clear. Many people starting out in research find themselves faced with the task of reviewing literature, often because it seems a gentle way to start in research or because someone else inflicts it upon them. It is not an exercise in its own right, but a precursor to a better understanding of the field you wish to explore.

What is the Literature Review?

A literature review is just a classification and evaluation of what scholars and researchers have written on a topic. Literature reviews then can be organized according to a guiding concept, such as a research objective, thesis or central problem.

An analogy I often use is that it's rather like me asking yon to bake a particular type of cake and bring it in next week so that I could enter it into a competition. Most people would need some guidance. Their first stop would be a cookbook (or, more likely, several to compare types of cakes, ingredients required, length of time to prepare and cook). This is your literature review. You have a task to accomplish and questions to answer; thus, you find the most up-to-date, current information to see how others have done it, what they found, why they found it, how it relates to the question and whether it worked. You can now tackle your cake baking better informed, and the likelihood of producing a prize-winning specimen is greatly improved.

A literature review should set the scene for addressing a particular research question and should identify what is current in the field. It also allows a researcher to refine the research question based on the experiences of others. For example, you may find that a particular method is problematic, or you may get some ideas for how to do things better, as well as how not to do them.

The objective of a literature review is not to rack up points by listing as many articles as possible. It is to demonstrate your intellectual ability to recognize relevant information, synthesize and evaluate it according to the guidelines and the concept you have determined for yourself. It is not simply what literature exists, but also includes your informed evaluation of the literature.

Organizing the Literature Review

When beginning a literature review, most people hit their first hurdle when they realize an opinion is required. How can you know whether this article is any good or not? Without some guidance, it can be difficult, as is the case for any acquired skill. First, you need a prescribed system to boost your confidence, and then you need to practice.

An effective process for reviewing literature involves 2 key skills: information seeking and critical appraisal. Information seeking is the ability to search the literature efficiently to identify a set of potentially useful articles. Critical appraisal is the ability to identify which studies are unbiased and valid.

How you organize your review also is fundamentally important because the reader wants more than just a descriptive list of articles and books. It is always a bad sign when every paragraph of your review begins with the names of researchers.

Organize your review into useful, informative sections that present themes or identify trends. A literature review should not just summarize what you read, but also should present a conceptually organized synthesis of the results of your search. It must organize information and relate it to the thesis or research question you are developing and synthesize results into a summary of what is and is not known. It should identify controversy when it appears in the literature and develop questions for further research.

To help with the process, ask yourself the following questions about the overall review:

* What do I want to know? First, it is essential that you clearly understand the specific research question that you want the literature review to answer. Too many times I have seen researchers begin a project without having a clearly defined question, and six months later they still are not sure what they want to know.

* What type of literature review is this? Is my review based on theory, methodology, policy, quantitative research or qualitative research? The type of review you want to do influences the type of material that you need to review.

* What is the scope of my literature review? Has your search been wide enough to ensure that you found all the relevant material, yet narrow enough to exclude irrelevant material?

* Is there a specific relationship between the literature I've chosen to review and the problem I've formulated? It is imperative that each article relate to the specific question or problem you've identified.

* Have I critically analyzed the literature? Double-check to ensure that your review is more than a list of articles and summaries. Discussing the strengths and weaknesses of the cited material can be helpful, as can citing and discussing studies contrary to your perspective.

* Will the reader find my literature review relevant, appropriate and useful?

You should be able to answer all of these questions--some before you start your review and some on completion. In the meantime, ask yourself the following questions for each article that you include in your review:

* Has the author clearly articulated a central problem or issue?

* Is its significance (scope, severity, relevance) discussed?

* What are the strengths and limitations of the way the author has formulated the problem or issue?

* Could the problem have been approached more effectively from another perspective?

* Has the author evaluated the literature relevant to the problem or issue?

* Does the author include literature with opposing opinions?

* How accurate, valid and reliable are the measurements used in the methods section?

* Is the method sufficiently detailed to be replicable?

* Is the analysis of the data accurate and relevant to the research question?

* Are the author's conclusions valid and based upon reported data and analysis?

* Does this article help me better understand the central problem or issue?

* In what ways is the article useful for practice?

* What are the article's strengths and limitations?

* How does this article relate to the question I am developing?

Practicalities and Logistics

Most articles are available electronically and, therefore, easy to access online. Numerous search engines and databases are available; your selection will depend on your research area. It is possible in most instances to download an article directly into a reference manager program such as Endnote. This makes life much easier when writing your review because you can insert citations directly from your database and adjust the referencing style to suit the journal for which you are writing. However, you should check with your proposed journal whether it can accommodate automatic referencing programs because these sometimes interfere with the publication process.

How you select statements of specific interest is very much an individual choice. You may highlight these (manually or electronically) within the text of an article you've saved or "write as you read," which some people prefer. The best way to overcome the hurdle of what to write first is to put your fingers on the keyboard and start writing. The alternative is to accumulate ever-increasing piles of articles and keep counting them and sorting them into different (and ever-changing) stacks.

You will have noticed that each article brings its own references, which can be a useful resource. However, it is not acceptable to "cite a citation." In other words, do not cite a reference from an article when you have not read the actual paper. If Brown cited a reference from Scutt, you must read Scutt's paper if you use the reference in your article.

When reviewing articles in a particular field, the same names often recur. This is quite usual as researchers establish their reputation and their publishing records increase. It can help to familiarize yourself with the "big names" in a field, and many journals have e-mail alerts when new work is published on a particular topic.

Be brave! You have to start somewhere and have a practice run. Some people are naturally adept at this type of writing, but most people need practice and constructive feedback to refine their technique. Writing for review purposes is probably quite different from anything you've done before. The good news is that it's quite easy to correct writing style early on before bad habits set in, so seek advice early in the process.