Ground Ambulance Industry Trends, 2017-2020

Section 50203(b) of the Bipartisan Budget Act of 2018 amended section 1834(1)(17)(A) of the Social Security Act to require the Centers for Medicare & Medicaid Services (CMS) to collect cost, revenue, utilization, and other information from representative samples of ground ambulance organizations. To meet this requirement, CMS developed the Medicare Ground Ambulance Data Collection System (GADCS) and used a stratified sampling approach to select four representative cohorts of organizations covering nearly all of the over 10,000 organizations that bill Medicare annually. CMS’ sampling approach aimed to ensure that the selected organizations were representative across four key organizational characteristics: (1) enrollment as a Medicare provider versus supplier, (2) ownership category, (3) service area population density, and (4) volume of Medicare ground ambulance transports. CMS selected the first two annual GADCS cohorts using Medicare fee-for-service claims and enrollment data from 2017 and 2018, respectively, and the third and fourth annual cohorts using data from 2020. As a result of the coronavirus disease 2019 (COVID-19) public health emergency, CMS delayed some GADCS selection, data collection, and reporting timelines to allow ground ambulance organizations to focus on their operations and patient care. The later GADCS data collection and reporting timelines raise important questions regarding the extent to which GADCS cohorts, which were selected using historical data, generalize to more recent cohorts of organizations.

To explore whether ground ambulance organizations have changed over time, including through the COVID-19 pandemic, we examined trends in transport volume (i.e., the number of ground ambulance transports paid for by Traditional [fee-for-service] Medicare) and the characteristics of organizations billing Medicare for ground ambulance services from 2017 through 2022. These analyses of changes in ground ambulance organizations over time focused on the four characteristics included in CMS’ sampling approach. Of these four organizational characteristics, transport volume may be the most likely to change over time. A prior analysis of Medicare fee-for-service claims found a gradual reduction in transport volume between 2017 and 2019 and a substantial decline from late 2019 through 2020, coinciding with the onset of the COVID-19 pandemic. Utilization of health care services generally declined across most service categories, including emergency department visits, inpatient stays, and ambulatory care, over the same early-pandemic period. (Although other studies show utilization has returned to near prepandemic levels for many categories of health care services, little is known about the postpandemic recovery for Medicare ground ambulance services.)

For this analysis, we combined Medicare fee-for-service claims data; CMS’ Medicare Provider Enrollment, Chain, and Ownership System data; and Medicare enrollment data. The analysis presented here focuses on 2017 through 2022. Our analytic approach also explored how Medicare Advantage (MA) enrollment growth over time could affect the volume of Traditional Medicare ground ambulance transports. Furthermore, we assessed which International Classification of Diseases, Tenth Revision, Clinical Modification diagnosis codes were most frequently reported with Medicare fee-for-service claims for ground ambulance transports and explored how these lists of diagnosis codes changed between 2017 and 2022. Finally, we examined the share of transports that were to or from an end-stage renal disease (ESRD) facility for each year. We found that the volume of Traditional Medicare transports declined considerably over time, from more than 14.6 million transports in 2017 to fewer than 10.8 million in 2022. Although the largest portion of the decrease in overall transport volume occurred during the start of the COVID-19 pandemic in 2020, this trend continued in 2021 and 2022, even as health care use in other sectors returned to nearly prepandemic levels. The other organizational characteristics remained fairly consistent over time, although there were slight changes in the distribution of ground ambulance organizations across ownership type categories, with decreasing proportions of non-profit and increasing proportions of government organizations. We found that adjusting for county-level changes in the percentage of Medicare beneficiaries enrolled in Traditional Medicare (as opposed to MA plans) from 2017 to 2022 explained roughly two-thirds of observed declines in Traditional Medicare ground ambulance transports over the same period. We also found a sharp decline in the share of Traditional Medicare ground ambulance transports to or from ESRD facilities over time. This share remained fairly steady (around 16 percent) from 2017 through 2021. However, we found a sharp decrease in 2022, with only 9.5 percent of all transports being to or from an ESRD facility. The recent expansion of MA eligibility to include newly enrolling beneficiaries with ESRD (as part of the 21st Century Cures Act) may have contributed to this decrease in 2022.

In sum, this analysis found only slight changes in ground ambulance organizational characteristics from 2017 to 2022, with the exception of a long-term, gradual decline in Traditional Medicare transport volume. Analyses using GADCS data could consider implementing such methodological approaches as weighting to account for this trend when describing results in terms that are most relevant to the current population of Medicare ground ambulance organizations.