Abstract
Accurate data extraction and their synthesis form the basis of appropriate conclusions of a systematic review. Systematic reviewers should extract ALL data relevant to the review question, not just the outcome data. Data to be extracted include baseline characteristics of study participants, information related to study methodology and outcomes and other relevant information. If published articles have given the results using figures instead of actual numbers, specialised software that convert images to pixel values may be utilised to obtain the actual data values. Tools such as Plot Digitizer, WebPlotDigitizer, Engauge, Dexter, Ycasd and GetData Graph Digitizer can be used for this purpose. When unable to extract data from available reports or to seek clarifications, the reviewers could contact the original investigators. Data extraction should be performed using pre-piloted forms independently by at least two reviewers to ensure accuracy. A high level of diligence is required to minimise errors during the stage of data extraction.
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Moon, K., Rao, S. (2021). Data Extraction from Included Studies. In: Patole, S. (eds) Principles and Practice of Systematic Reviews and Meta-Analysis. Springer, Cham. https://doi.org/10.1007/978-3-030-71921-0_6
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DOI: https://doi.org/10.1007/978-3-030-71921-0_6
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