From Use of VA and Medicare services by dually eligible veterans with psychiatric problems, by Carey et al. and based on FY1999 data:
Results suggest a distinction between aged and disabled veterans in choice of sector for outpatient care. The distance from a VA [Veterans Health Service] outpatient medical or MH [mental health] facility did not make a difference in the allocation of expenditures between VA and Medicare for aged veterans. However, distance from a VA outpatient medical or MH facility did matter for disabled veterans, perhaps because they relied much more heavily on VA than on Medicare for MH/SA [mental health/substance abuse] services than did the aged veterans. Among all veterans, the disabled had 3.9 times more VA than Medicare MH/SA expenditures, compared with 1.4 times for the aged. The failure of our results to indicate significant associations between geographic proximity to VA outpatient services and choice of sector by aged veterans may be due to the relatively small portion of medical expenditures that is accounted for by outpatient care, particularly for the elderly. Total VA and Medicare expenditures may be dominated more by costly inpatient care in this group, even for MH/SA services, if elderly veterans have more comorbidities than younger veterans and are more likely to be treated for MH/SA problems at a VA inpatient facility.
This is interesting because it suggests the extent to which MH/SA VA patients use non-VA care (in this case Medicare) differs by age. That matters because, by pooling VA, Medicare, and Medicaid data, we can typically see all the care a patient enrolled in both VA and Medicare (and possibly Medicaid) receives. By contrast, we typically do not have access to private health plan data for non-elderly VA patients who are not on Medicare. Consequently, we don’t know as much about non-VA care for them. It sure would be convenient to presume that patterns of non-VA use for the Medicare-VA duals are similar to those who are not on Medicare. But these results suggest that may not be a good assumption, at least circa 1999 and for MH/SA diagnosed patients.
Do you see the contortions one has to go through due to lack of access to private health plan data? This is a major concern that those who would prefer a more (or fully) private insurance system rarely address.