The EpiLink Record Linkage Software

Summary

Objectives: Record linkage, the process of bringing together separately compiled but related records from different databases, is essential in many areas of biomedical research. We developed a record linkage program (EpiLink), which employs a simple mathematical approach. We describe the program and present results obtained testing it in a linkage task.

Methods: EpiLink was designed to be flexible with user-friendly settings to tailor linkage and operating parameters to specific linkage tasks, and employ deterministic, probabilistic or sequential deterministic-probabilistic linkage strategies as required. The user can also standardize data format, examine linkage results and accept or discard them. We used EpiLink to link a subset of cases of the Lombardy Cancer Registry (20,724 records) with the Social Security file of the population (1,021,846 records) covered by the registry. The linkage strategy was deterministic, followed by several probabilistic linkage steps.

Results: Manual inspection of the results showed that EpiLink achieved 98.8% specificity and 96.5% sensitivity.

Conclusions: EpiLink is a practical and accurate means of linking records from different databases that can be used by non-statisticians and is efficient in terms of human and financial resources.

Keywords

Cancer registry - record linkage - computer program - follow-up methods

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