During this stage, pieces of data will be extracted from the full-text of studies that have met your inclusion criteria.
Determining the data to be collected will be based on your research question and should be specified in the protocol.
Potential elements to be extracted may include: participant demographics, study design and methodology, results, citation information, etc. and is typically presented as a Table of Evidence.
The steps in data extraction are:
Depending on review type, a critical appraisal of studies found to meet inclusion criteria is to be conducted.
Critical appraisal is the process of systematically evaluating the validity of research and its relevance to specific clinical situations.
There are tools, checklists, and other resources to assist with this stage of the project and should be specified in the protocol.
After critical appraisal/quality assessment is performed, tabulate and summarize the results.
Once you have selected the most reliable and relevant studies, you will need to combine all the findings of the individual studies using textual or statistical methods. The purpose of the synthesis is to answer your research question.
Synthesis involves pooling the extracted data from the included studies and summarizing the findings based on the overall strength of the evidence and consistency of observed effects.
Depending on your review type and objectives, forms of synthesis may include one or more of the following:
The synthesis method should be identified in your protocol.
A Synthesis Matrix or Table of Evidence can be used to organize your findings by themes.
NYU Libraries provide a sample review matrix template that can be copied and edited via google sheets.
