Table 1.

Examples of data sources for meta-analyses

Summary or aggregate level data			Individual patient level data
Published literature	Registries	Clinical study reports
Publications, available through publication databases, provide aggregate results, including effect estimates, measures of precision, or adverse event counts observed in treatment arms and comparator arms	Registries are online databases that report information about timing, design, and results of clinical trials (eg, ClinicalTrials.gov). Results reported on registries often include summary effect estimates or adverse event counts	Clinical study reports are detailed documents that describe design and results of clinical trials. Full reports include efficacy and safety data, but do provide patient specific information	Raw data from individual participants in clinical trials