Medicare is the single largest purchaser of laboratory testing in the United States, yet test results associated with Medicare laboratory claims have historically not been available.
The purpose of this study was to describe both the linkage of laboratory results data to Medicare claims and the completeness of these results data. In a subgroup of beneficiaries initiating angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, we also demonstrate the generalizability of Medicare beneficiaries with laboratory values compared with those without laboratory values. We end with a discussion of the limitations and potential uses of these linked data.
We obtained information about laboratory orders and results for all Medicare fee-for-service beneficiaries in 10 eastern states who had outpatient laboratory tests conducted by a large national laboratory services vendor in 2011. Using a combination of direct identifiers and patient demographic characteristics, we linked patients in these laboratory data to Medicare beneficiaries, enabling us to associate test results with existing claims.
Nearly all patients in the laboratory data were able to be linked to Medicare beneficiaries. There were over 2 million distinct beneficiaries with nearly 125 million specific test results in the laboratory data. For specific tests ordered in an outpatient or office setting in these 10 states, between 5% and 15% of them had linked laboratory data. Medicare beneficiaries initiating angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers who had laboratory results data had similar patient characteristics to those without results data.
This novel linkage of laboratory results data to Medicare claims creates unprecedented opportunities for conducting comparative effectiveness research related to patient safety and quality.
*Duke Clinical Research Institute
†Department of Medicine
‡Center for the Study of Aging and Human Development, Duke University School of Medicine, Durham, NC
§Center for Health Services Research in Primary Care
∥Geriatrics Research, Education and Clinical Center
¶Ambulatory Care Service, Durham Veterans Affairs Medical Center, Durham, NC
This research was funded by Robert Wood Johnson Foundation’s Health Care Financing and Organization Initiative (#70922) and the Centers for Medicare and Medicaid Services. This work was also supported by the Office of Research and Development, Health Services Research and Development Service, Department of Veterans Affairs, and M.L.M. was also supported by a Research Career Scientist Award from the Department of Veterans Affairs (RCS 10-391).
The views expressed in this article are those of the authors and do not necessarily reflect the position or policy of Duke University or the Department of Veteran Affairs.
The authors declare no conflict of interest.
Reprints: Bradley G. Hammill, DrPH, Duke Clinical Research Institute, P.O. Box 17969, Durham, NC 27715. E-mail: firstname.lastname@example.org.