In summary, the methods section of both the protocol and the review should detail:
The data categories that are to be collected;
How verification of extracted data from each report will be verified (e.g. extraction by two review authors, independently);
Whether data extraction is undertaken by content area experts, methodologists, or both;
Piloting, training and existence of coding instructions for the data collection form;
How data are extracted from multiple reports of the same study;
How disagreements are handled if more than one author extracts data from each report.