Achieving equity in Medicare disproportionate share payments to rural hospitals: an assessment of the financial impact of recent and proposed changes to the disproportionate share hospital payment formula.

Historically, the Medicare Disproportionate Share Hospital (DSH) payment program has been less favorable to rural hospitals: eligibility thresholds were higher and the payment adjustment was smaller for rural than for urban hospitals. Although the Medicare, Medicaid, and SCHIP Benefit Improvement and Protection Act (BIPA) of 2000 established a uniform low-income threshold and increased the magnitude of the adjustment for certain small and rural hospitals as a means to promote payment equity, the DSH distribution formula continues to vary by location. This study examines how the DSH revisions mandated under BIPA are likely to affect rural hospitals' financial performance and simulates the financial impact of implementing a uniform DSH payment adjustment. Using data from the 1998 Medicare cost report and impact files, this study found that two-thirds of both rural and urban hospitals would have qualified for DSH payments following BIPA compared with only one-fifth of rural hospitals and one-half of urban hospitals prior to BIPA. Although the impact of BIPA revisions on rural hospitals' total margins were found to be modest, the financial impact of a uniform payment adjustment would be somewhat greater: rural hospitals' average total margins would have increased by 1.6 percentage points. Importantly, 20% of rural hospitals with negative total margins would have been "in the black" if rural and urban hospitals were reimbursed using the same DSH formula. These findings suggest that elimination of rural and urban disparities in DSH payment could strengthen the rural health care safety net.