Enhancement of Clinical Data Repository by Linkage to State Mortality Files

We report a method and preliminary results for merging state mortality data into a hospital Clinical Data Repository (CDR). A broadly inclusive set of potential matches for our CDR patient population was obtained from the state Death Registry at the Virginia Center for Health Statistics (VCHS). For each possible match, a total weighted score was calculated according to the level of agreement between seven identifiers. The scoring method was validated by consideration of that population of CDR patients known to have died in the hospital. We conclude that the method represents a practical way to enhance hospital data with important outcomes information. Background The CDR at the University of Virginia Health System is a retrospective data repository comprising linked inpatient data (7 years), outpatient data (4 years), physician billings (7 years), and laboratory results (5 years). Hospital databases like the CDR are only able to record in-hospital death and are otherwise missing patient mortality data required by clinicians for health research purposes. Previous work indicates that accurate linkage of hospital data to vital statistics files is feasible'. Thus, by establishing a transferable operational protocol, we linked the CDR with mortality information from the statewide death registry at the VCHS.