MRI utilization model: results of a validation study

In 1989, the American Hospital Association (AHA) conducted a survey to assess the predictive accuracy of the second generation Magnetic Resonance Imaging (MRI) Utilization Model. Of the 172 hospitals that had purchased the AHA model in 1987, 101 (59%) responded to the survey. Half of those responding were not offering MRI services yet, 10% had decided not to offer MRI services or were undecided, and 15% were operating services for less than four months. Our results are based on a sample of 21 hospitals. The major findings of this study are: 1. The "Current Year DRG Projection" is a good predictor of early utilization of MRI. 2. The "ICD-9-CM Projection" and the "1990 DRG Projection" are indicators of full utilization of MRI or steady state. Hospitals that have more experience with the technology and an educated referral base of physicians are achieving these projections. The "ICD-9-CM Projection" could be considered a more conservative projection of full utilization and the "1990 DRG Projection" a more aggressive full utilization projection. 3. Computed tomography (CT) usage has not changed much at the current stage of MRI utilization. Applications for use of CT have expanded. 4. An emerging area for MRI is the study of the extremities. The average volume of MRI studies of the extremities performed by hospitals in our sample was about 11% of the total MRI scan volume, but the range extended from a low of 1% to a high of 20%.