A systematic review is a rigorous and structured method of synthesizing existing research evidence on a specific question or topic. Unlike traditional literature reviews, which may be narrative or selective, systematic reviews follow a transparent, replicable process to identify, evaluate, and summarize all relevant studies, minimizing bias and ensuring comprehensive coverage of the available evidence.
The process usually starts with a well-defined research question, then moves on to creating a clear plan or protocol. This outlines what kinds of studies will be included or excluded, how the research will be searched for, and how the relevant data will be collected and analyzed.
Researchers then conduct thorough searches across multiple databases and sources to identify studies that meet the criteria. Each study is assessed for quality and relevance before findings are synthesized, either narratively or through statistical techniques like meta-analysis.
What are the Key Features of a Systematic Review? #
Key features of a systematic review include:
- Predefined protocol: Systematic review ensures consistency and reduces bias.
- Comprehensive search: It covers published and sometimes unpublished studies.
- Critical appraisal: It evaluates the validity and reliability of each study.
- Evidence synthesis: It summarizes findings to answer the research question.
What are the Benefits of a Systematic Review? #
Some major benefits of systematic review are:
- It supports evidence-based decision-making.
- It identifies any gaps in existing research.
- It provides a solid foundation for policy or practice recommendations.
What are the Limitations of a Systematic Review? #
Like any other method, a systematic review also has certain limitations:
- It is time-and resource-intensive.
- The findings are only as strong as the quality of included studies.
A systematic review is, thus, a valuable method for bringing clarity and credibility to complex research questions by drawing on a wide body of existing evidence in a methodical and transparent way.
List of recommended resources #
For a broad overview #
Systematic Review | Definition, Example & Guide
This article by Shaun Turney on Scribbr gives an overview of systematic reviews, comparing it to other kinds of reviews such as meta-analysis, literature review and scoping review. The article also explains when to conduct a systematic review along with providing a step-by-step example of a systematic review for better understanding.
This video by Cochrane gives a succinct explanation of why systematic reviews are important and how they are done. It also includes an explanation of how the effects of interventions are compared in order to provide evidence.
For in-depth understanding #
This paper gives an in-depth understanding of systematic reviews providing a 24-step guide on how to perform a systematic review and meta-analysis of observational studies and clinical trials.
Methodological Guidance Paper: The Art and Science of Quality Systematic Reviews
This article by Patricia A. Alexander highlights key challenges that authors may face when conducting a systematic review, from formulating a meaningful research question to transparently documenting the search process and analyzing data patterns. It also offers practical suggestions to improve the quality and relevance of systematic reviews for educational research, practice, and policy.
Case study #
This systematic review aims to complement the existing evidence on the effectiveness of cash transfer programmes in improving schooling outcomes and help inform the debate surrounding the design of cash transfer programmes.
Interventions to Prevent or Reduce Violence Against Women and Girls : A Systematic Review of Reviews
This paper presents a systematic review of reviews, offering a comprehensive synthesis of existing evidence on interventions aimed at preventing violence against women and girls (VAWG). It explores a wide range of geographical settings, various forms of violence, and the diverse strategies employed to address and reduce VAWG globally.
