How to evaluate and improve the quality and credibility of an outcomes database: validation and feedback study on the UK Cardiac Surgery Experience.

Objectives: To assess the quality and completeness of a database of clinical outcomes after cardiac surgery and to determine whether a process of validation, monitoring, and feedback could improve the quality of the database.

Design: Stratified sampling of retrospective data followed by prospective re-sampling of database after intervention of monitoring, validation, and feedback.

Setting: Ten tertiary care cardiac surgery centres in the United Kingdom.