Online detection of potential duplicate medications and changes of physician behavior for outpatients visiting multiple hospitals using national health insurance smart cards in Taiwan

Objectives: Doctor shopping (or hospital shopping), which means changing doctors (or hospitals) without professional referral for the same or similar illness conditions, is common in Hong Kong, Taiwan and Japan. Due to the lack of infrastructure for sharing health information and medication history among hospitals, doctor-shopping patients are more likely to receive duplicate medications and suffer adverse drug reactions. The Bureau of National Health Insurance (BNHI) adopted smart cards (or NHI-IC cards) as health cards in Taiwan. With their NHI-IC cards, patients can freely access different medical institutions. Because an NHI-IC card carries information about a patient's prescribed medications received from different hospitals nationwide, we used this system to address the problem of duplicate medications for outpatients visiting multiple hospitals.

Methods: A computerized physician order entry (CPOE) system was enhanced with the capability of accessing NHI-IC cards and providing alerts to physicians when the system detects potential duplicate medications at the time of prescribing. Physician responses to the alerts were also collected to analyze changes in physicians' behavior. Chi-square tests and two-sided z-tests with Bonferroni adjustments for multiple comparisons were used to assess statistical significance of differences in actions taken by physicians over the three months.

Results: The enhanced CPOE system for outpatient services was implemented and installed at the Pediatric and Urology Departments of Taipei Medical University Wan-Fang Hospital in March 2007. The "Change Log" that recorded physician behavior was activated during a 3-month study period from April to June 2007. In 67.93% of patient visits, the physicians read patient NHI-IC cards, and in 16.76% of the reads, the NHI-IC card contained at least one prescribed medication that was taken by the patient. Among the prescriptions issued by physicians, on average, there were 2.36% prescriptions containing at least one medication that might be duplicative to the prior prescriptions stored in NHI-IC cards. The rate of potential duplicate medication alerts for the Pediatric Department was higher than that for the Urology Department (2.78% versus 1.67%). However, the rate of revisions to prescriptions was higher in the Urology Department than the Pediatric Department. Overall, the rate of physicians reviewing and revising their prescriptions was 29.25%; the rate of physicians reviewing without revising their prescriptions was 43.62%; the rate of physicians turning off the alert screens right after the screens popped up (overridden) was 27.13%. Thus, physicians accepted alerts to review their prescriptions with patients in most situations (72.87%). Moreover, over the study period, the rate of total revisions made to prescriptions increased and the "overridden" rate decreased.

Conclusions: Our approach enhances the capability of CPOE systems using NHI-IC cards as a nationwide infrastructure to provide more complete patient health information and medication history sharing among hospitals in Taiwan. Thus, our system can provide a better prescribing tool to help physicians detect potential duplicate medications for frequent doctor-shopping patients and hence enhance patient safety across hospital boundaries. However, the effectiveness of detecting duplicate medications with our approach is very much dependent on the completeness of NHI-IC cards, which in turn primarily depends on physician use of the cards when prescribing.