A formal literature review is an evidence-based, in-depth analysis of a subject. There are many reasons for writing one and these will influence the length and style of your review, but in essence, a literature review is a critical appraisal of the current collective knowledge on a subject. Rather than just being an exhaustive list of all that has been published, a literature review should be an informative, personal but unbiased synopsis of the information, providing a balanced view that includes conflicting findings and inconsistencies, as well as established and current thinking.

A literature review differs from a systematic review, which addresses a specific clinical question by combining the results of multiple clinical trials (an article on this topic will follow as part of this series of publications). A formal literature review is also an extension of the information gathering you might do to get a personal insight to the background of a topic and requires more than a quick scan of the literature and a few summary bullet points.

Conducting a literature review is essential for developing a research idea, to consolidate what is already known about a subject and to enable you to identify any knowledge gaps and how your research could contribute to further understanding. This will help you develop hypotheses and to frame your research question; see the article by Anastasiadis et al. for further reading.

Once you’ve carried out a piece of research, a literature review is also crucial for evaluating your data and determining their relevance and clinical utility. Research data without context can be meaningless. A literature review will enable you to identify other research that supports or corroborates your findings as well as results that differ, enabling you to position your research in the field.

The dissemination of your research findings, whether by publication in a peer-reviewed paper or by oral presentation, will use the information gathered for a literature review, thus providing reference points for your new data and helping to identify and deliver the potential impact of your research.