Higher Medicaid-to-Medicare reimbursement ratios (MMRR) are linked to increased likelihood of Medicaid patients receiving CT, MR, ultrasound, and x-ray imaging, researchers have reported.
The study results suggest that increases in MMRRs could translate into improved imaging access for Medicaid patients, wrote a team led by Eric Christensen, PhD, of the Harvey L. Neiman Health Policy Institute in Reston, VA. The findings were published December 18 in the Journal of the American College of Radiology.
"Imaging more broadly offers significant value to patients, providers, and health care systems when used appropriately through disease prevention, detection, diagnosis, prognosis, and in the delivery and monitoring of precise, minimally invasive treatment," the group explained. "Hence, the potentially beneficial aspects of increased Medicaid reimbursement, although not [necessarily] specific to imaging, are broad-based."
Medicare reimbursement levels are set by individual states, and they vary across the U.S., but "no study has examined the relationship between Medicaid reimbursement and utilization of imaging," the team wrote.
To address this knowledge gap, Christensen and colleagues conducted a study that assessed associations between diagnostic imaging use with the state-level professional payment MMRR, computing these ratios by imaging modality. They estimated the likelihood of an individual having imaging as well as the average number of imaging studies performed, setting gender-modality combinations and controlling for patient characteristics. The research included data from 4.9 million Medicaid patients.
The group found the following:
| Analysis of effect of Medicaid-to-Medicare reimbursement ratio (MMRR) on imaging use | |
|---|---|
| Modality | Median MMRR |
| CT | 0.82 |
| MR | 0.87 |
| Nuclear medicine | 0.76 |
| Ultrasound | 0.85 |
| X-ray or fluoroscopy | 0.82 |
It also reported that the probability of an individual having imaging was 25.9% at the 75th percentile of the MMRR distribution compared with the 25th percentile for CT, 25.9% higher for MR, 21.4% higher for ultrasound, and 31.8% higher for x-ray.
Why do these results matter? Because below-cost reimbursement may "diminish provider acceptance of Medicaid patients, resulting in worsening access differences," according to the researchers.
"The results of this study empirically show the magnitude of this reimbursement-utilization trade-off for imaging, which is that Medicaid patients in states at the third quartile of the MMRR distribution have a probability of receiving imaging that is at least 21% more than those at the first quartile of the MMRR distribution for all modalities except nuclear medicine," they concluded. "Hence, the results show that the MMRR is important because having Medicaid coverage is not synonymous with equal access to care."
The complete study can be found here.
