 This is an introduction to the concept of systematic literature reviews and meta-analyses. What do you think of when you are asked to conduct a literature review? Your answer will probably vary depending on your past experiences with literature reviews through class projects as a precursor to future research or as an effort in and of itself. Literature reviews may take many forms and use different methodologies depending on the purpose of your review and or the question you aim to address. Approaches may be selective where authors are just looking for some resources to illustrate a point while other methodologies require an exhaustive search and comprehensive set of information. Reviews also vary with regard to the extent to which authors assess the quality and or risk of bias of each included reference. There are other considerations too, but these two continuums will be helpful to conceptualize the landscape of literature reviews. The approach we are likely to think of when we first hear the term literature review probably falls into the category of traditional reviews. These tend to be descriptive overviews or topic summaries, sometimes presented as a means to provide background to a larger work and sometimes as a standalone review providing trends, updates, common practice, or a broader overview of a topic. Reviews that fall into this category also vary with regard to structure. In some cases, the approach an author takes to find, select, and review material is not explained at all whereas other approaches might fall into a loosely defined category of structured reviews. Systematic reviews on the other hand are highly structured, clearly defined, and aim to be comprehensive and account for bias and or quality of a material that is included in the review as well as the bias and or quality of the review itself. It's easy to confuse the concept of a structured review with a systematic review as the terms are so similar. However, the term systematic review refers to a very specific procedure that requires authors to adhere to published protocols and reporting guidelines. The systematic review approach aims to answer a specific question or set of questions by collecting, evaluating, and synthesizing all available relevant information. The result is a qualitative discussion of existing information about a topic, how the references do or do not speak to one another, gaps in the field, trends across research, and how available evidence may inform actions or decisions. Systematic reviews may also include a quantitative synthesis, often using the statistical approach called a meta-analysis. In short, meta-analyses take the findings from several studies to create a new statistic. This new analysis is based on the combined samples of included studies and is therefore more powerful than the results of the individual studies it comprises. Finally, a cornerstone of the systematic review is transparency and replicability. In other words, the review should be documented and reported with enough detail that another research team can accurately replicate the approach. Because of these characteristics, the systematic review and or meta-analysis is considered the pinnacle of quality when it comes to evidence for decision-making. Thus, despite the fact that systematic reviews are reviews of primary research and or other information, they provide a unique and significant contribution to the field. Therefore, a systematic review is considered original research in and of itself and is typically pursued and published as a standalone project. As you may have guessed, the systematic review is resource-intensive, requiring a large time commitment and a full team of individuals with specific expertise related to each stage of the review. Generally speaking, you should plan to spend at least one year working with at least two other individuals if you choose to pursue your own systematic review. We'll discuss these requirements in more detail throughout this series. Pursuing a systematic review is a great opportunity for your team to strengthen their understanding of a research area and to assess methods in your field. Likewise, these publications tend to be highly cited and provide a strong research record that can help when you're applying for grants. You might find that a systematic review approach doesn't fit your research question or current resource conditions, but there are other kinds of comprehensive reviews that you may consider. For example, we use scoping reviews to map or illustrate the field of information related to a comparatively broader question And restricted reviews, or rapid reviews, is a term for systematic review with some kind of constraint such as a tight deadline, a restricted search, or not having access to a full team. So, looking at the literature review landscape, you can see how different types of reviews might fall upon the matrix. Likewise, you've probably noticed that the range within each type is broad, as there is a lot of variation between and within each category. Choosing the right approach for your question, objectives, and capacity is important. In this series, we'll be focusing only on the systematic review and meta-analysis. However, the tools and approaches we cover are valuable for any review type. If you are interested in exploring any of the other review types that exist, please check out the additional reading for this video and or ask a librarian for help. You can also check out the resources accompanying this video to learn more about the support and services from the Evidence Synthesis Services team at the University Libraries at Virginia Tech.