Subject and Course Guides: Advanced Reviews: What are Advanced Reviews?

Advanced Reviews Defined

Advanced Review is a term used by UNL Libraries to categorize review methods that are conducted systematically and are part of the Evidence Synthesis umbrella of research methods. Evidence Synthesis is a group of methods primarily focused on the analysis of secondary data and marked by the principles of transparency, reproducibility, replicability, and bias reduction. At its most basic level, evidence synthesis is just what it sounds like, a synthesis of the existing evidence on a topic. Many different research methods fall under this umbrella including full Advanced Reviews, like systematic reviews and scoping reviews, as well as many methods for data synthesis that fall outside of our particular scope. See more in the graphic below.

In the literature and across disciplines, 'evidence synthesis' and 'systematic review' are sometimes used interchangeably. However, for greater clarity and precision, we use the term systematic review to mean a specific type of evidence synthesis review that follows set standards and guidelines. Please refer to our Systematic Reviews guide for more information on this type of review.

Introduction to Advanced Reviews
A brief blog post that defines advanced reviews and situates them within their development in the evidence synthesis literature.

Advanced reviews and evidence synthesis

Advanced reviews fall within a broader category of evidence synthesis. Evidence synthesis includes advanced review frameworks, like systematic reviews, scoping reviews, and qualitative evidence syntheses, and individual synthesis methods that can be used within these frameworks. These include quantitative synthesis methods including meta-analyses and content analyses, and qualitative synthesis methods, including meta-aggregations, meta-syntheses, meta-narratives, concept analyses, thematic syntheses, and meta-ethnographies.

View and download full size image (PDF)

Evidence Synthesis: What is it and why do we need it?

Video produced by Evidence Synthesis Ireland

Evidence synthesis research guides for graduate students

Evidence Synthesis Guide 1: Understanding Evidence Synthesis [How-to Guide]
Learn more about evidence synthesis from my guides in Sage Research Methods.
After reading this How-to Guide, students should be able to
• understand the definition, purpose, characteristics, and principles of evidence synthesis methodologies;
• understand the history and development of synthesis methods such as meta-analyses and review frameworks such as systematic reviews and scoping reviews;
• understand why these methods were developed and the important part they play in the research ecosystem; and
• identify research projects for which evidence synthesis methods are most appropriate.
Evidence Synthesis Guide 2: How to Decide Which Evidence Synthesis Type Is Right for You [How-to Guide]
After reading this How-to Guide, students should be able to
• identify the different types of ES frameworks and synthesis methods and understand the differences between them;
• increase transparency, replicability, and reproducibility and minimize bias within their own research;
• better understand how to use their research aims to identify the most appropriate review framework and/or synthesis method for their project;
• identify the essential differences between different ES synthesis methods, including the data types they are designed to analyze; and
• understand rapid reviews and living systematic reviews as developing approaches to conducting a systematic review under specific conditions.

Tips for conducting an advanced review

Identify a target journal before you begin your review. If you know where you want to publish, you can follow their requirements from the very beginning.
Find published reviews on a similar topic to your own and identify what guidelines they used for their review to help inform your own decision making.
The key to a publishable review is good planning and organization from the very beginning. It is helpful to meet with a librarian before you begin your review to learn more about the resources and strategies available to help you get and stay organized through the process.
You will inevitably save yourself time and many headaches throughout the process by documenting everything! Decide to add or remove a key term from your search strategy? Document that you did and why. Which person performed each step in the process? What decisions were made along the way? You may not need these notes, but it is much better to have them and not need them than it is to need them and not have them during peer review of your article.

Time and resource considerations

Be sure to be realistic about the amount of time it will take to conduct a thorough review. Advanced reviews are much more time and resource-intensive than traditional literature reviews and require a multi-person research team, usually 3 or more to meet guidelines and best practices. Advanced reviews may also require the participation of a librarian and a statistician or other specialist in data analysis. These review methods were developed out of a need to provide the highest level of evidence for evidence-based clinical practice, policy-making, and future research. They adapt the scientific method for review to incorporate research integrity and validity into the process. Not every research question is best addressed by an advanced review. Before embarking on an advanced review, it's important to clearly identify your reasons, match your reasons with the most appropriate review method, and fine tune a research question or questions that can feasibly be answered by your chosen methodology.

PredicTER tool
This tool will help you get an idea of the timeline for conducting a review. While it is based on a systematic review timeline specifically, it is applicable more generally to all advanced reviews.
Timeline visualization
View our own timeline visualization, created by Gabe Bruguier

How do Advanced Reviews Differ from a Traditional Literature Review?

This table is a further aid in comparing the aims of a traditional literature review with a systematic review.

	Traditional Literature Review	Advanced Reviews
Review Question/Topic	Topics may be broad in scope; the goal of the review may be to place one's own research within the existing body of knowledge, or to gather information that supports a particular viewpoint.	Starts with a well-defined research question to be answered by the review. Reviews are conducted with the aim of finding all existing evidence in an unbiased, transparent, and reproducible way.
Searching for Studies	Searches may be ad hoc and based on what the author is already familiar with. Searches are not exhaustive or fully comprehensive.	Attempts are made to find all existing published and unpublished literature on the research question. The process is well-documented and reported.
Study Selection	Often lack clear reasons for why studies were included or excluded from the review.	Reasons for including or excluding studies are explicit and informed by the research question.
Assessing the Quality of Included Studies	Often do not consider study quality or potential biases in study design.	Systematically assesses risk of bias of individual studies and overall quality of the evidence, including sources of heterogeneity between study results.
Synthesis of Existing Research	Conclusions are more qualitative and may not be based on study quality.	Bases conclusion on quality of the studies and provide recommendations for practice or to address knowledge gaps.