A systematic review answers a defined research question by collecting and summarising all empirical evidence that fits pre-specified eligibility criteria.
A meta-analysis is the use of statistical methods to summarise the results of these studies.
Systematic reviews, just like other research articles, can be of varying quality. They are a significant piece of work (the Centre for Reviews and Dissemination at York estimates that a team will take 9-24 months), and to be useful to other researchers and practitioners they should have:
clearly stated objectives with pre-defined eligibility criteria for studies
explicit, reproducible methodology
a systematic search that attempts to identify all studies
assessment of the validity of the findings of the included studies (e.g. risk of bias)
systematic presentation, and synthesis, of the characteristics and findings of the included studies
Stages to conducting a Systematic Review
Conducting a systematic review at the master's level typically involves the following stages:
1. Topic Selection: Identify a research question or topic of interest that requires a comprehensive review of existing literature.
2. Protocol Development: Develop a clear and detailed protocol outlining the research question, search strategy, inclusion/exclusion criteria, and methods for data extraction and analysis. Ensure each stage is both reliable and valid
Literature Search: Conduct a systematic search of relevant databases, gray literature, and other sources to identify all potentially relevant studies.
Study Selection: Screen the retrieved articles based on predetermined inclusion/exclusion criteria to select studies that meet the research question's criteria.
Data Extraction: Extract relevant data from the selected studies using a standardized data extraction form, including study characteristics, participant demographics, interventions, outcomes, and study quality assessment.
Quality Assessment: Evaluate the methodological quality and risk of bias of the included studies using appropriate tools and frameworks.
Data Synthesis: Analyze and synthesize the data from the included studies, using statistical methods or qualitative analysis techniques, to answer the research question.
8. Results Presentation: Present the findings in a structured and organized manner, including tables, figures, and narrative descriptions. Summarize the main findings, patterns, and trends observed across the studies.
9. Interpretation and Discussion: Discuss the implications of the findings, address limitations, and explore potential biases or sources of heterogeneity. Compare the results with existing evidence and theories, and draw conclusions.
10. Conclusion and Recommendations: Summarize the main findings and their implications. Provide recommendations for future research, clinical practice, or policy development based on the review's outcomes.
11. Reporting: Prepare a comprehensive report or thesis that adheres to the guidelines and standards of systematic reviews, such as PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses).
It's important to note that these stages may vary slightly depending on the specific requirements of the master's program or the nature of the research topic.
References:
Moller AM, Myles PS. What makes a good systematic review and meta-analysis? BJA. 2016. 117(4):428-430.