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7.6.1  Introduction

In most Cochrane reviews, the primary source of information about each study is published reports of studies, usually in the form of journal articles. One of the most important and time-consuming parts of a systematic review is extracting data from such reports. The data collection form will usually be designed with data extraction in mind.


Electronic searches for text can provide a useful aid to locating information within a report, for example using search facilities in PDF viewers, internet browsers and word processing software. Text searching should not be considered a replacement for reading the report, however, since information may be presented using variable terminology.