Researchers at Research Foundation Have Reported New Data on Medicare and Medicaid (Controlling confounding of treatment effects in administrative…

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Researchers at Research Foundation Have Reported New Data on Medicare and Medicaid (Controlling confounding of treatment effects in administrative data in the presence of time-varying baseline confounders)

By a News Reporter-Staff News Editor at Insurance Weekly News -- A new study on Medicare and Medicaid is now available. According to news reporting originating from Minneapolis, Minnesota, by VerticalNews correspondents, research stated, "Confounding, a concern in nonexperimental research using administrative claims, is nearly ubiquitous in claims-based pharmacoepidemiology studies. A fixed-length look-back window for assessing comorbidity from claims is common, but it may be advantageous to use all historical claims."

Our news editors obtained a quote from the research from Research Foundation, "We assessed how the strength of association between a baseline-identified condition and subsequent mortality varied by when the condition was measured and investigated methods to control for confounding. For Medicare beneficiaries undergoing maintenance hemodialysis on 1 January 2008 (n=222 343), we searched all Medicare claims, 1 January 2001 to 31 December 2007, for four conditions representing chronic and acute diseases, and classified claims by number of months preceding the index date. We used proportional hazard models to estimate the association between time of condition and subsequent mortality. We simulated a confounded comorbidity-exposure relationship and investigated an alternative method of adjustment when the association between the condition and mortality varied by proximity to follow-up start. The magnitude of the mortality hazard ratio estimates for each condition investigated decreased toward unity as time increased between index date and most recent manifestation of the condition. Simulation showed more biased estimates of exposure-outcome associations if proximity to follow-up start was not considered. Using all-available claims information during a baseline period, we found that for all conditions investigated, the association between a comorbid condition and subsequent mortality varied considerably depending on when the condition was measured."

According to the news editors, the research concluded: "Improved confounding control may be achieved by considering the timing of claims relative to follow-up start."

For more information on this research see: Controlling confounding of treatment effects in administrative data in the presence of time-varying baseline confounders. Pharmacoepidemiology and Drug Safety, 2015;25(3):269-77. (Wiley-Blackwell - www.wiley.com/; Pharmacoepidemiology and Drug Safety - onlinelibrary.wiley.com/journal/10.1002/(ISSN)1099-1557)

The news editors report that additional information may be obtained by contacting D.T. Gilbertson, Chronic Disease Research Group, Minneapolis Medical Research Foundation, Minneapolis, MN, United States. Additional authors for this research include B.D. Bradbury, J.B. Wetmore, E.D. Weinhandl, K.L. Monda, J. Liu, M.A. Brookhart, S.K. Gustafson, T. Roberts, A.J. Collins and K.J Rothman.

Keywords for this news article include: Minnesota, Minneapolis, Epidemiology, United States, Health Policy, Drugs and Therapies, Medicare and Medicaid, North and Central America.