National specialty trends in billable diagnostic ultrasound in the ED: analysis of Medicare claims data

doi:10.1016/j.ajem.2014.09.002

The American Journal of Emergency Medicine

Volume 32, Issue 12, December 2014, Pages 1470-1475

https://doi.org/10.1016/j.ajem.2014.09.002 Get rights and content

Abstract

Objective

To assess recent national specialty trends in the use of diagnostic ultrasound (US) services in the Emergency Department (ED) setting.

Methods

We searched aggregated 1998-2012 Medicare Part B Master Files for ED diagnostic US studies, excluding cardiac and ophthalmic examinations. Studies were classified by body part and interpreting specialty. Subsequent analysis was performed for higher-volume services rendered by emergency physicians for which discrete codes were present longitudinally for complete vs limited examinations. National trends were analyzed.

Results

From 1998 to 2012, paid ED US studies interpreted by radiologists, emergency physicians, and all other physicians increased by 332% (from 221 712 to 735 858 examinations), 4454% (from 561 to 24 992), and 251% (from 26 961 to 67 787), respectively. The fraction of ED US examinations interpreted remained around 90% for radiologists, increased from 0.2% to 3% for emergency physicians, and decreased from 11% to 8% for other physicians. The fraction of complete abdominal and complete retroperitoneal studies interpreted by emergency physicians remained less than 1% from 1998 through 2012. However, emergency physicians experienced disproportionate growth in limited examinations (from 1% to 9% for abdominal studies and from < 1% to 20% for retroperitoneal studies). Likewise, the fraction of (typically targeted) chest studies interpreted by emergency physicians increased from less than 1% to 63%.

Conclusion

From 1998 to 2012, there was substantial growth in ED US studies for Medicare beneficiaries interpreted by radiologists and emergency physicians alike. For more commonly performed services distinguishable as complete vs limited in nature, growth in services by emergency physicians was most dramatic for less complex services.

Introduction

Ultrasonography in the emergency department (ED) setting offers tremendous potential benefit for patient care. For numerous conditions, compared with other imaging modalities, ultrasound can provide a rapid and accurate diagnosis at lower cost and without radiation exposure [1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12]. In addition, the appropriate application of ultrasound in the ED setting can decrease length of stay and improve patient satisfaction [13], [14], [15], [16]. In at least some centers, when emergency physicians directly perform and interpret ultrasound examinations, they achieve faster examination times and increased imaging access at off-hours when radiology-performed ultrasound may not be available [5], [17], [18], [19], [20], [21]. To this end, emergency physicians have been actively promoting the expansion of ultrasound services by the specialty by incorporating basic ultrasonography training into residency programs, creating dedicated emergency ultrasound fellowships, and allocating funds toward the acquisition of ultrasound equipment [22], [19], [23], [24], [25], [20], [26], [21]. Because of these ongoing and aligned efforts, ultrasonography performed by emergency physicians is likely to exhibit continued growth [27], [28], [29], [26].

Although the use of ultrasound by emergency physicians has expanded, overall ultrasound use in the ED setting across all specialties has undergone substantial growth as well [30]. Relative changes in the performance of ED ultrasound by emergency vs other physician specialties remain unknown, particularly with regard to paid services. This knowledge gap could be critically important in fully understanding changes in care delivery and appropriate physician compensation. If the growth in ultrasonography by emergency physicians is less than that by other specialties, then current specialty expansion efforts may in fact not be having their intended effect. On the other hand, if growth in ultrasound by emergency physicians is outpacing growth by other specialties, then a more precise knowledge of the specific ultrasound examinations with the greatest growth (and growth potential) could be useful in better understanding the nuances of these successful expansion efforts. Such information is important for guiding decisions regarding the optimal allocation of clinical and education-related resources.

Given the above considerations, our aim was to assess national specialty trends in diagnostic ultrasound services in the ED setting from 1998 to 2012, using Medicare Part B data to identify paid services. Analyses were performed for various categories of ultrasound examinations, as well as for select individual complexity-differentiatable ultrasound examinations performed at a relatively higher volume. Our intent was to provide insights into the volume of ED ultrasound examinations interpreted and billed by different specialties over time, and identify potential shifts in the distribution of certain examinations between such specialties during the study period.

Section snippets

Study design

This was a retrospective descriptive study using annual Medicare Physician Supplier Procedure Summary (PSPS) Master Files from 1998 through 2012, which were obtained from the Center for Medicare & Medicaid Services. These designated Public Use Files contain no patient-specific data. Accordingly, this study has been deemed to not represent human subject research and was deemed review-exempt by our institutional review board.

Physician Supplier Procedure Summary files contain aggregated Medicare

Results

Table 1 shows trends in ED ultrasound use overall and by different specialties during the study period. The total number of paid ultrasound examinations performed in the ED setting on Medicare Part B beneficiaries increased by 332% from 1998 to 2012 (from 249 234 to 828 637 examinations, respectively). During this time, the number of paid studies interpreted by radiologists increased by 332% (from 221 712 to 735 858 examinations); by emergency physicians, 4454% (from 561 to 24 992

Discussion

Between 1998 and 2012, there was substantial growth (by > 300%) in paid ultrasound examinations performed in the ED setting on Medicare fee-for-service beneficiaries. This growth was observed across all body areas evaluated for radiologists, emergency physicians, and other specialists alike. Thus, the growth cannot be attributed to changes in patterns of care by any single specialty but likely reflects broader trends in the role of ultrasonography in acute patient evaluation and management in

Limitations

A primary limitation of this study is its derivation from an administrative Medicare claims data set that focuses exclusively on a Medicare fee-for-service population. We acknowledge that trends may be different within the general population of non-Medicare patients being cared for in the ED setting. However, similar data sets pertaining to the privately insured population are generally proprietary and not publicly available for analysis. Such data sources represent opportunities for future

Conclusion

From 1998 to 2012, there was substantial growth in ultrasound use in the ED setting among Medicare fee-for-service beneficiaries. There were also specialty shifts in examination complexity during this period, with emergency physicians showing greatest growth in less complex abdominal and less complex retroperitoneal studies and what we believe are less complex chest studies, whereas nonemergency nonradiology physicians showed the greatest growth in vascular studies. Although the relative

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^☆☆: Conflicts of interest: None.

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Original ContributionNational specialty trends in billable diagnostic ultrasound in the ED: analysis of Medicare claims data☆,☆☆

Abstract

Objective

Methods

Results

Conclusion

Introduction

Section snippets

Study design

Results

Discussion

Limitations

Conclusion

J Am Coll Surg

Am J Emerg Med

Am J Emerg Med

Ann Emerg Med

Am J Emerg Med

Ann Emerg Med

J Am Coll Radiol

J Am Coll Radiol

J Am Coll Radiol

Use of pelvic computed tomography and sonography in women of reproductive age in the emergency department

J Ultrasound Med

Utilization of FAST (Focused Assessment with Sonography for Trauma) in 1999: results of a survey of North American trauma centers

Am Surg

Bedside emergency department ultrasonography availability and use for blunt abdominal trauma in Canadian pediatric centres

CJEM

Bedside pediatric emergency evaluation through ultrasonography

Pediatr Radiol

Use of ultrasound and surgery in adults with acute scrotal pain

ANZ J Surg

Fewer unnecessary appendectomies following ultrasonography and CT

Ned Tijdschr Geneeskd

Prospective analysis of the effect of physician experience with the FAST examination in reducing the use of CT scans

Emerg Med Australas

Diagnostic value of ultrasonography in the evaluation of blunt abdominal trauma

Diagn Interv Radiol

Original Contribution
National specialty trends in billable diagnostic ultrasound in the ED: analysis of Medicare claims data☆,☆☆