Statistical Modeling for Errors in Record Linkage Applied to SEER Cancer Registry Data

Record linkage joins together two or more sources. The product of record linkage is a file with one record per individual containing all the information about the individual from the multiple files. The problem is difficult when a unique identification key is not available, there are errors in some variables, some data are missing, and files are large. Probabilistic record linkage computes a probability that records from on different files pertain to a single individual. Some true links are given low probabilities of matching, whereas some non links are given high probabilities. Errors in linkage designations can cause bias in analyses based on the composite data base. The SEER cancer registries contain information on breast cancer cases in their registry areas. A diagnostic test based on the Oncotype DX assay, performed by Genomic Health, Inc. (GHI), is often performed for certain types of breast cancers. Record linkage using personal identifiable information was conducted to associate Oncotype DC assay results with SEER cancer registry information. The software Link Plus was used to generate a score describing the similarity of records and to identify the apparent best match of SEER cancer registry individuals to the GHI database. Clerical review was used to check samples of likely matches, possible matches, and unlikely matches. Models are proposed for jointly modeling the record linkage process and subsequent statistical analysis in this and other applications.