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Published on: November 27, 2019
Practical guidance for using multiple data sources in systematic reviews and meta-analyses (with examples from the
Evan Mayo-Wilson1, Tianjing Li1, Nicole Fusco1
1Department of Epidemiology, Johns Hopkins University Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD, 21205, USA.
Systematic reviews can be improved by carefully selecting and linking multiple data sources. Following a prespecified protocol for data extraction and outcome assessment reduces bias and research waste.
Area of Science:
- Medical research methodology
- Evidence-based medicine
Background:
- Systematic reviews synthesize evidence from multiple studies.
- Trial data can be reported across various sources (e.g., journal articles, conference abstracts).
- Differences in data sources can influence systematic review outcomes.
Purpose of the Study:
- To provide practical guidance for effectively using multiple data sources in systematic reviews.
- To enhance the reliability and reduce bias in systematic review findings.
Main Methods:
- Developed recommendations based on the Multiple Data Sources in Systematic Reviews (MUDS) study experience and prior evidence.
- Proposed a six-point practical guidance framework for managing multiple data sources.
Main Results:
- Recommended specifying data sources beforehand.
- Advised linking individual trials across multiple sources using modified PRISMA flowcharts.
- Stressed following prespecified protocols for data extraction, outcome definition, and handling discrepancies.
- Emphasized identifying included data sources and assessing potential influence on results.
- Suggested data sharing to reduce bias and research waste.
Conclusions:
- Systematic use of multiple data sources, guided by a clear protocol, is crucial for robust systematic reviews.
- Adherence to the proposed guidance can improve the accuracy and efficiency of evidence synthesis.
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