Building a successful enterprise master patient index: a case study.

To ensure success in building an enterprise master patient index (MPI), an understanding of the complexities of the internal duplicate files and the overlap population is essential. Merging multiple MPIs is complicated and requires time and a commitment to accuracy. Most organizations underestimate the importance of the following ground rules for building an enterprise MPI: Internal duplicates need to be corrected; linking patient files with a statistical weighting algorithm is far superior to using rigid criteria; there are more overlap patient files than an organization usually perceives; an imprecise and incomplete base of demographic data will multiply the error rate for the enterprise; preliminary data analysis is critical to avoid linkage problems during conversion; and accurate data collection and monitoring are imperative for ongoing data integrity. The article discusses the major steps involved in creating an enterprise MPI and recommends solutions to common problems encountered during conversion.