Patient (or person) master index (PMI) data quality activities in public, acute healthcare facilities in the state of Victoria, Australia were evaluated in terms of health information management-information technology best practice including data standards and practice guidelines. The findings indicate that, whilst data quality and linkage activities are undertaken, many are limited in scope or effectiveness. In view of published evidence that: (i) duplicate patient files pose significant risks by reducing information available for clinical decision-making; and (ii) quality and clinical risk management require, as a measurable outcome, continuous monitoring of duplicate files, improvements to PMI data quality practices are recommended.