Hospital outpatient department billing is a poor indicator of primary care practice integration with hospital systems

OBJECTIVE

To test the reliability of Medicare claims in measuring vertical integration. We assess the accuracy of a commonly used measure of integration, primary care physician (PCP) practices billing Medicare as a hospital outpatient department (HOPD) in claims.

DATA SOURCES AND STUDY SETTING

Medicare fee-for-service claims, IQVIA, and CPC+ practice surveys for this study.

STUDY DESIGN

We compare measures of integration from Medicare claims to self-reported indicators of integration from IQVIA and a survey of CPC+ participating practice sites.

DATA COLLECTION/EXTRACTION METHODS

We measure integration by using site-of-service billing in the 100% sample of Medicare Carrier claims from 2017-2020. In the IQVIA SK&A (2017-2018), OneKey (2019-2020), and practice survey data (2017-2019), we use self-reported responses to measure integration.

PRINCIPAL FINDINGS

We find that currently most PCP practices sites that report themselves as being integrated with a health system do not bill as an HOPD. In 2017, 11% of CPC+ practices were identified as being vertically integrated in claims, while the equivalent numbers in SK&A and surveys were 52% and 54% integration, respectively. A t-test found that both datasets significantly differed from claims (Survey: 41.3%-45.1%; SK&A: 45.3%-51.1%); this gap persists in 2018-2019.

CONCLUSION

Measuring physician-hospital vertical integration accurately is integral to determining consolidation. The overwhelming majority of PCP practice sites not billing as an HOPD may reflect Medicare regulatory changes that have reduced the financial incentives for doing so. These findings have implications for researchers that study the growth in PCP-hospital integration in health care markets.

Spending per Medicare Beneficiary Is Higher in Hospital-Owned Small- and Medium-Sized Physician Practices

OBJECTIVE

To examine the relationship of physician versus hospital ownership of small- and medium-sized practices with spending and utilization of care.

DATA SOURCE/STUDY SETTING/DATA COLLECTION

Survey data for 1,045 primary care-based practices of 1-19 physicians linked to Medicare claims data for 2008 for 282,372 beneficiaries attributed to the 3,010 physicians in these practices.

STUDY DESIGN

We used generalized linear models to estimate the associations between practice characteristics and outcomes (emergency department visits, index admissions, readmissions, and spending).

PRINCIPAL FINDINGS

Beneficiaries linked to hospital-owned practices had 7.3 percent more emergency department visits and 6.4 percent higher total spending compared to beneficiaries linked to physician-owned practices.

CONCLUSIONS

Physician practices are increasingly being purchased by hospitals. This may result in higher total spending on care.