Trends in Utilization Rates of the Various Imaging Modalities in Emergency Departments: Nationwide Medicare Data From 2000 to 2008

doi:10.1016/j.jacr.2011.04.004

Journal of the American College of Radiology

Volume 8, Issue 10, October 2011, Pages 706-709

https://doi.org/10.1016/j.jacr.2011.04.004 Get rights and content

Purpose

To study utilization trends in the various imaging modalities in emergency departments (EDs) over a recent multiyear period.

Methods

The nationwide Medicare Part B databases for 2000 to 2008 were queried. Medicare's location codes were used to identify imaging examinations done on ED patients. All diagnostic imaging Current Procedural Terminology^® codes were grouped by modality. For each code, the database provides procedure volume; utilization rates per 1,000 beneficiaries were then calculated. Medicare's physician specialty codes were used to determine provider specialty. Utilization trends were studied between 2000 and 2008.

Results

The overall utilization rate per 1,000 beneficiaries for all imaging in EDs increased from 281.0 in 2000 to 450.4 in 2008 (+60%). The radiography utilization rate rose from 227.3 in 2000 to 294.3 in 2008 (+29%, 67 accrued new studies per 1,000). The CT rate rose from 40.0 in 2000 to 130.7 in 2008 (+227%, 90.7 accrued new studies per 1,000). The ultrasound rate rose from 9.6 in 2000 to 18.7 in 2008 (+95%, 9.1 accrued new studies per 1,000). Other modalities had much lower utilization. In 2000, CT constituted 14% of all ED imaging, but by 2008, it constituted 29%. In 2008, radiologists performed 96% of all ED imaging examinations.

Conclusions

The rate of utilization of imaging is increasing in EDs. Growth is by far the most pronounced in CT, in terms of both the growth rate itself and the actual number of accrued new studies per 1,000 beneficiaries. Radiologists strongly predominate as the physicians of record for all ED imaging.

Section snippets

Methods

The data source was the Medicare Part B Physician/Supplier Procedure Summary Master Files for 2000 through 2008. The files contain information on all medical services provided to the Medicare fee-for-service population (34.98 million in 2008). For each code in the fourth edition of the Current Procedural Terminology^® (CPT^®) manual, the files indicate the annual procedure volume, the specialties of the physician providers, and the locations (or places of service) where the procedures were

Results

Figure 1 shows the trend in the overall utilization rate of NDI in EDs in the Medicare fee-for-service population from 2000 to 2008. The rate per 1,000 beneficiaries showed a steady upward progression from 281.0 in 2000 to 450.4 in 2008 (+60%), for a compound annual growth rate (CAGR) of 6.1%.

Figure 2 breaks down utilization data into the 3 major ED modality categories: radiography, CT, and ultrasound. Radiographic examinations were the most commonly performed, increasing from a rate of 227.3

Discussion

Our data demonstrate fairly rapid and consistent growth of total NDI in EDs between 2000 and 2008. Because the numbers refer to rates per 1,000 beneficiaries, the trends are independent of volume changes that might result from an increase in the number of beneficiaries. Growth occurred in all 3 of the major modalities (radiography, CT, and ultrasound). However, growth in CT was considerably more rapid than in either radiography or ultrasound during the period under study, in terms of both the

Conclusions

The rate of utilization of NDI in EDs is steadily increasing. The increase is most pronounced in CT, which is being used at a much higher rate than ultrasound and a far higher rate than MRI. The share of ED imaging attributable to CT doubled from 2000 to 2008. Radiologists strongly predominate in ED CT, radiography, and noncardiac ultrasound. Although this fact is encouraging for radiologists, it is likely that hospitals will begin to expect them to work more closely with ED physicians in the

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: This study was supported in part by a grant from the American College of Radiology (Reston, Va).

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Original articleTrends in Utilization Rates of the Various Imaging Modalities in Emergency Departments: Nationwide Medicare Data From 2000 to 2008

Purpose

Methods

Results

Conclusions

Section snippets

Methods

Results

Discussion

Conclusions

J Am Coll Radiol

Health insurers and medical-imaging policy—a work in progress

N Engl J Med

Annual number of visits to hospital emergency departments: United States, 1992-2005National Hospital Ambulatory Medical Care Survey

Increasing utilization of computed tomography in the adult emergency department, 2000-2005

Emerg Radiol

Original article
Trends in Utilization Rates of the Various Imaging Modalities in Emergency Departments: Nationwide Medicare Data From 2000 to 2008