Contains quality-assessed abstracts of systematic reviews, including a summary of the review and a critical appraisal of its overall quality. The Cochrane Central Register of Controlled Trials (CENTRAL). Is a database that contains details of articles of Controlled trials and other studies of healthcare interventions from bibliographic databases (majorly MEDLINE and EMBASE), and other published and unpublished sources that are difficult to access.[3] The Cochrane Methodology Register (Methodology Register).