Verification of information in a large medical database using linkages with external databases.

Efforts to utilize Uniform Hospital Discharge Data Sets (UHDDS) for epidemiological studies have been hampered by the limitations of those databases. The purpose of this paper is to illustrate that linking to external databases can provide the verification necessary to overcome many of those limitations. This method has dramatically altered study design at the Connecticut Hospital Research and Education Foundation and has provided an efficient method for specifying data collection weaknesses within the resident databases.