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7.3.1  What are data?

For the purposes of this chapter, we define ‘data’ to be any information about (or deriving from) a study, including details of methods, participants, setting, context, interventions, outcomes, results, publications and investigators. Review authors should plan in advance what data will be required for their systematic review, and develop a strategy for obtaining them. The following sections review the types of information that should be sought, and these are summarized in Table 7.3.a. Section 7.4 reviews the main sources of the data.