Medicare's national coverage determinations in diagnostic radiology: examining evidence and setting limits.

Objective: To systematically review and summarize the Center for Medicare and Medicaid Services (CMS) national coverage determination (NCDs) pertaining diagnostic imaging technologies from 1999 through 2010.

Methods: All NCDs pertaining to diagnostic imaging were identified from the Tufts Medical Center NCD database. The variables under study included the quality of the clinical evidence and the final coverage determination.

Regression analysis on the variation in efficiency frontiers for prevention stage of HIV/AIDS.

Objectives: To investigate how the cost effectiveness of preventing HIV/AIDS varies across possible efficiency frontiers (EFs) by taking into account potentially relevant external factors, such as prevention stage, and how the EFs can be characterized using regression analysis given uncertainty of the QALY-cost estimates.

Methods: We reviewed cost-effectiveness estimates for the prevention and treatment of HIV/AIDS published from 2002-2007 and catalogued in the Tufts Medical Center Cost-Effectiveness Analysis (CEA) Registry. We constructed efficiency frontier (EF) curves by plotting QALYs against costs, using methods used by the Institute for Quality and Efficiency in Health Care (IQWiG) in Germany.

Medicare's national coverage decisions for technologies, 1999-2007.

An analysis of Medicare national coverage decisions (NCDs) from 1999 through 2007 reveals that the Centers for Medicare and Medicaid Services (CMS) considers the available evidence as no better than fair for most of the technologies considered. Still, the CMS issues favorable decisions in 60 percent of the cases it takes on, although almost always with conditions placed on coverage. Since enactment of the 2003 Medicare Modernization Act, which legislated maximum review times for NCDs, the CMS has eliminated "long duration" decisions (more than one year) and has issued several "coverage with evidence development" decisions, which promise flexibility but also carry implementation challenges.