Addition of an error correction facility to a functioning data management system

The National Institute of Neurological and Communicative Disorders and Stroke conducted the Stroke Data Bank, a prospectively collected database, in collaboration with investigators from four clinical centers. A distributed data entry system was originally designed to permit data entry and editing using microcomputers. As data collection progressed, it became evident that the editing system was inadequate. A central data editing component was added to the system, with responsibility for error correction remaining at the clinical centers. This report summarizes the design of the error correction facility and demonstrates the feasibility of its late implementation.