Abstract: A system is provided for merging hospital database records and assuring real-time patient field updates during registration processes. A find tool identifies potential duplicate records, data overlays and duplicate guarantor numbers within a master patient index (MPI) or enterprise master patient index (EMPI) database of a hospital database. After the data is scored, a merge tool merges the data and gives the user the ability to review potential duplicate records online and decide on an operation to be performed thereon. A guard tool complements the merge tool as a means for preventing duplicate records and data overlays during the registration process. The user can continue with the new registration or choose an existing record from the duplicate matching screen as the data is inputted, thereby keeping the current inputs clean in “real-time.