Trends in Medicare Part B Imaging Volumes, 2003–2010

In looking at aggregate procedure counts in Medicare Part B medical imaging over the past eight years, the drama that unfolded between 2003 and 2010 is nowhere to be seen. Both rapid escalation in the imaging growth rate and a subsequent, nearly equivalent decline in volumes are lost in a compound annual growth rate (CAGR) of –0.9% over eight years. That’s according to a new analysis of the Medicare Physician/ Supplier Procedure Summary annual master files, 2003 to 2010, performed by the newly established Harvey L. Neiman Health Policy Institute (HPI). The HPI provided three tables based on partially scrubbed Medicare Part B data for 2003 through 2010. Imaging-service unit counts, by imaging modality, performed by radiologists and nonradiologists, were presented for the office setting (Table 1) and for all places of service (Table 2). Also provided was a breakdown of radiologists’ and nonradiologists’ shares of imaging in office; inpatient hospital; and hospital outpatient, emergency-department, or other settings (Table 3). Radiology Business Journal compared the imaging-service units of radiologists and nonradiologists to arrive at the growth rate for 2003 through 2007, when imaging hit its peak number of units in this population (Table 4). We also looked at the percentage change in units between 2007 and 2010, a period during which the number of imaging procedures performed in this population declined by 15% (Table 5), as well as the change in the same period in the office setting only (Table 6). We then looked at the changes in the site of service between 2003 and 2010 (see figure).

Table 1. Service Units, Office, by Modality
Table 2. Service Units, All Settings, by Modality

A few cautionary notes about the data, lest readers be inclined to draw more than is warranted from the numbers: Imaging counts, in IDTF settings, are included in the nonradiologist imaging category. CMS counts IDTF imaging not as a place of service, but as a specialty—and due to the inability to separate radiologist-owned IDTFs from other IDTFs, IDTF imaging is included in the nonradiologist counts. What would appear to be a dramatic decline in nuclear imaging from 2009 to 2010 and a smaller (but significant) decline in mammography are both the results of a CMS decision to bundle certain myocardial-imaging and mammography codes. Spike and Decline Over the eight-year span of 2003 through 2010, volumes dropped slightly in 2004 and then hit their peak in 2007 (Table 2), the year that the DRA reductions were fully implemented. Medicare paid for a total of 218,826,552 units of medical imaging in 2007, after which imaging volumes steadily declined by 15% over the next three years (Table 5). The decline was even more pronounced in the office setting (Table 6), where imaging volumes declined by 25% between 2007 and 2010. Danny Hughes, PhD, research director and senior research fellow at the HPI, says, “It’s a fresh story, but it’s also an old story. No one who deals with these data is surprised anymore that imaging has slowed down; in 2007, you had a marked drop-off in imaging.”

Table 3. Service Units, by Place of Service and Modality

Hughes says that the HPI will be issuing its first policy brief addressing this and providing in-depth analysis. He attributes a small part of the decline to the DRA and other health policies—and a more significant portion to technology maturation. “There was a period, in the early 2000s, where you really had a ramping up,” he notes, adding that high-end technology has begun to diffuse. “Once you have the latest and greatest in these technologies, and the technologies are fully diffused, utilization adjusts to account for these new technologies and their use—then, it plateaus,” he says. Hughes is not projecting further declines, and he anticipates that volumes will plateau (except, perhaps, in rural areas, where access to imaging centers and technology is currently limited). Long and Short Views The broad trend in imaging-volume reductions over eight years (Tables 1–3) indicates that volumes for imaging performed by radiologists appear to have declined slightly more than those for imaging performed by nonradiologists in the office setting, but less than for nonradiologist-performed imaging in all settings. When viewed over the past three years, however, the drop in volumes has taken a greater toll on nonradiologist-performed imaging, and that’s true in all settings. In the office setting, radiologist-performed imaging declined 19% from 2007 through 2010; nonradiologist-performed imaging declined 28% (Table 6). In all settings (including hospital inpatient, outpatient, and emergency-department settings), radiologist-performed imaging declined 6% between 2007 and 2010; nonradiologist-performed imaging declined by 27%, suggesting that some self-referral might have had its incentives reduced or reversed by payor policies put in place since 2006. A portion of the decline also can be attributed to CMS policy decisions that required the bundling of certain codes. “This is, perhaps, not a mainstream talking point yet,” Hughes says, “but anyone working with these data for the past three years is aware of it, and it is just now rolling out in the peer-reviewed literature.” While the overall eight-year trend for all modalities shows a –0.9% annual growth rate from 2003 to 2010, some individual modalities registered single-digit annual growth rates, despite the steep declines of the past three years: CT grew 5.2% annually and MRI grew 4.4% per year (Table 2). These two high-tech modalities show higher eight-year CAGRs in the office setting: For CT, the CAGR was 8.9% annually for 2003 through 2010, and MRI had a 4.8% CAGR over the same period, offering a scent of the meteoric growth that initiated CMS scrutiny (Table 1). Growth rates for nonradiologist-performed imaging in both modalities and both settings were higher than growth rates for radiologist-performed imaging in CT and MRI. Place of Service A trend that is more interesting to observe over the eight-year span is the shift in place of service (Table 3 and figure). In 2003, 39.3% of imaging done by all physicians was office based; 26.67% was performed in the inpatient hospital setting; and 34% was delivered in an outpatient, emergency-department, or other setting.

Table 4. 2003–2007 Change in Service Units, All Settings, by Modality
Table 5. 2007–2010 Change in Service Units, All Settings, by Modality

By 2010, volumes in both office-based and inpatient hospital-based imaging had eroded, but the category of hospital outpatient, emergency-department, and other setting picked up share. In 2010, 35.8% of imaging performed by all physicians took place in the office setting; 23.4% of imaging occurred in the hospital inpatient setting; and 40.7% of imaging was performed in a hospital outpatient, emergency-department, or other setting. Office-based imaging peaked at 40.5% in 2007, the same year that overall imaging volumes hit their highest level (Table 3). Hospital inpatient imaging volumes peaked in 2004, at 28%, and appear to have been declining fairly steadily ever since. While volume for the hospital outpatient, emergency-department, or other setting has been flat or posting incremental increases since 2003 (when it accounted for a 34% share of imaging), it took off in 2007, peaking in 2010 with a 40.7% share. A number of factors could be driving this migration: The onset of the worst economic contraction since World War II might have played a role, as the unemployed population lost health benefits and more people sought care in emergency departments. Declines in hospital inpatient imaging volumes could be attributed partly to payors’ efforts to direct imaging to lower-cost outpatient sites and partly to deferred care. Office-based imaging volumes might have declined with the onset of the DRA, when the reimbursement environment became very challenging. The hospital inpatient and outpatient, emergency-department, or other settings were the dominant places of service for the radiologist both at the beginning of the period examined and at the end; however, the outpatient, emergency-department, or other setting grew in importance for radiologists over time. In 2003, 25.3% of all radiologist interpretations were provided in the office setting; 31.9% were done in the hospital inpatient setting; and 42.8% were done in the outpatient, emergency-department, or other setting (Table 3). In 2010, the breakdown was 21.4% office; 29.4% hospital inpatient; and 49.2% outpatient, emergency-department, or other. By far, the dominant place of service for nonradiologists was the office setting, which accounted for 61% of nonradiologist-interpreted imaging in 2003 and 62% in 2010 (Table 3). The Economic Downturn Hughes is reluctant to discuss the role that the economy might have played in the imaging downturn, pending the outcome of a separate line of research that the HPI is conducting across a broad range of medical services and delivery sites. “Overall, the number of procedures peaked in 2007,” Hughes says. “Some have increased, some have decreased, but considering the aggregate figures, we can’t really attribute the broad decline in imaging at this time to the economy.”

Table 6. 2007–2010 Change in Service Units, Office, by Modality
Figure. Share of Medicare Part B count of assigned service units, 2003 and 2010.

He continues, “For the most part, it is largely due to market saturation, technology maturation, DRA changes, and other regulatory changes that have caused imaging to shift. Preliminary data suggest that some of it is really just a shift from office-based to hospital-based imaging. That is something that bears greater scrutiny and something about which I won’t speak with authority until I have completed those studies.” Nonetheless, the data speak for themselves: The overall number of imaging procedures peaked in 2007 and has been on a steep downward slide since then. Both the office and the hospital-inpatient settings have lost share to the outpatient, emergency-department, or other setting. All of this brings up a question: Why does radiology remain in the crosshairs as a target for reimbursement reductions? “For a brief period of time, radiology grew at a much faster rate than many other services,” Hughes notes. “We also are a very tiny share of overall expenditures— now, with much slower growth—while other services are growing much more quickly.”