What should a registrar access to check if a patient has been seen at a hospital previously?

A registrar should access the master patient (person) index to check if a patient has been seen at a hospital previously. The master patient index is a comprehensive database that stores essential information regarding each patient, including unique identifiers, demographics, and historical visit details. This index allows registrars to easily determine if a patient has had past encounters with the hospital’s healthcare services, facilitating accurate patient identification and record-keeping.

This option stands out as the most relevant tool, as it is specifically designed to maintain records of all patients in the system. By using the master patient index, a registrar can avoid potential duplication of records and ensure they are referencing the correct patient history, which is critical for providing continuity of care. Other records such as appointment history, billing records, or clinical notes may provide fragmented information, but they do not serve the comprehensive purpose of identifying past patient interactions across the healthcare system as effectively as the master patient index does.