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; and
how disagreements are handled if more than one author extracts data from each report.