Interactive Spreadsheet for pairwise Corrected Covered Area for ‎assessment of Overlap of systematic reviews: A tool for Evidence-based ‎medicine

Interactive Spreadsheet for pairwise Corrected Covered Area for ‎assessment of Overlap of systematic reviews: A tool for Evidence-based ‎medicine


  • Pouyan keshavarz ‎1-‎ MSc of Medical Journalism, Medical Journalism Department, Shiraz University of Medical ‎Science.


Evidence-Based Medicine, Systematic Reviews, Overlapping Sources of Information, Corrected Covered Area


Evidence-based medicine is the main essence of clinical decision-making, particularly in the field of emergency medicine. Most important decisions in medicine are guided by aggregated data from systematic reviews and meta-analyses or guidelines. But, the number of systematic reviews has increased exponentially and to synthesize high-quality evidence with precision, umbrella reviews have merged. One critical aspect of umbrella reviews is assessing the overlap between studies included in different systematic reviews. An essential facet within umbrella reviews entails the rigorous assessment of the convergence among studies incorporated across different systematic reviews with similar objectives. Corrected covered area (CCA) is a method developed for assessing the amount of overlap between the systematic reviews that are included in an umbrella review. As assessing the CCA within multiple studies is a challenging assignment, here we have provided a free interactive tool to help researchers to calculate total CCA and pairwise CCA between the studies.


Funding:  None.

Data availability: Spreadsheet and online Python app are available at UiEM.  

Conflicts of interest: None.

Author contributions: PK contributed to all stages of the work.

Acknowledgments: The AI tool of ChatGPT was used for grammatical revisions and all AI written text is supervised by the human author.

Ethical considerations: Not applicable.

Supplementary file 1: CCA calculation spreadsheet

Note: The file should be redownloaded for new projects. Sample data is available in the file. The researcher should replace their own data in the file. 



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How to Cite

keshavarz, P. (2023). Interactive Spreadsheet for pairwise Corrected Covered Area for ‎assessment of Overlap of systematic reviews: A tool for Evidence-based ‎medicine. Updates in Emergency Medicine, 3(1). Retrieved from



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