Association of Hospital Characteristics and Diagnosis With the Repeat Use of CT and MRI: A Nationwide Population-Based Study in an Asian Country

OBJECTIVE. The objective of our study was to assess the association of hospital characteristics and diagnosis with repeated utilization of CT and MRI using the nationwide population-based Taiwan National Health Insurance database. MATERIALS AND METHODS. All CT and MR examinations for all health care services-including inpatient, outpatient, and emergency services-performed during 2004 and 2005 were identified. Logistic regression using generalized estimating equations was used for multivariate analysis to explore the relationships between hospital characteristics, diagnosis, and the use of CT and MRI repeated within 90 days. RESULTS. A total of 2,152,292 patients underwent CT and MR examinations during the study period, and 21.5% of those patients underwent repeat scanning within 90 days. The medical center had the highest rate of repeat scanning (24.9%) followed by the regional hospital (20.4%) and community hospital (13%). Repeat CT or MRI was most commonly performed of patients with a malignancy (31.8%), a neurologic disorder (24.0%), or a brain or spinal injury (25.3%). CONCLUSION. Our study shows that repeat use of CT and MRI within 90 days is high and is related to both diagnosis and hospital characteristics. Although the Taiwanese experience might not apply to all countries, this knowledge should aid in the review of health care policies so that guidelines for repeat scanning may be tailored to the different levels of hospitals (medical centers, 25%; regional hospital, 20%; community hospital, 13%) and to different diseases (malignant neoplasms, 32%; neurologic disorders and brain, neck, or spinal injury, 25%; other entities, 20%) to achieve maximum efficiency within a limited health care budget.