Introduction to mathematic analysis

vii+359hlm.;23c

Introduction to mathematical analysis

viii, 359 hlm. :il. ;22 cm

Association of the US Department of Justice Investigation of Implantable Cardioverter-Defibrillators and Devices Not Meeting the Medicare National Coverage Determination, 2007-2015

Importance The US Department of Justice (DOJ) conducted an investigation into implantable cardioverter-defibrillators (ICDs) not meeting the Centers for Medicare & Medicaid Services National Coverage Determination (NCD) criteria. Objective To examine changes in the proportion of initial primary prevention ICDs that did not meet NCD criteria following the announcement of the DOJ investigation at hospitals that reached settlements (settlement hospitals) and those that did not (nonsettlement hospitals). Design, Setting, and Participants Multicenter, longitudinal, serial cross-sectional analysis of 300 151 initial primary prevention ICDs among Medicare beneficiaries from January 1, 2007, through December 31, 2015, at 1809 US hospitals in the National Cardiovascular Data Registry (NCDR) ICD Registry, of which 452 hospitals (with 99 591 primary prevention ICDs) reached settlements with the DOJ. Exposures The DOJ investigation announcement in 2010. Main Outcomes and Measures Proportion of initial primary prevention ICDs not meeting NCD criteria. Results In January 2007, the proportion of initial ICDs not meeting NCD criteria was 25.8% (95% CI, 24.7% to 26.8%) at settlement hospitals and 22.8% (95% CI, 22.1% to 23.5%) at nonsettlement hospitals (P < .001). Over the study period, there was a 62.7% (95% CI, 59.2% to 66.1%) relative decrease and 16.1% (95% CI, 14.8% to 17.5%) absolute decrease in the proportion of ICDs not meeting NCD criteria at settlement hospitals compared with a 53.2% (95% CI, 50.4% to 56.0%) relative decrease and 12.1% (95% CI, 11.2% to 13.0%) absolute decrease in proportion at nonsettlement hospitals (P < .001 for both; P for interaction < .001). Trends significantly differed between hospital groups only in the period following the announcement of the DOJ investigation (January 2010-June 2011), with larger and more rapid decreases at settlement hospitals (P for interaction = .01). Over the study period, there was a 32.8% (95% CI, 29.9% to 35.7%) relative decrease and a 1703 ICDs (95% CI, 1520 to 1886) absolute decrease in the volume of primary prevention ICDs implanted at settlement hospitals compared with a 17.4% (95% CI, 14.8% to 20.0%) relative decrease and a 1495 ICDs (95% CI, 1249 to 1741) absolute decrease in volume at nonsettlement hospitals (P < .001 for both; P for interaction < .001), with more modest decreases or slight increases in secondary prevention ICD volume. These patterns were similar when examining ICD utilization among non–Medicare beneficiaries. Conclusions and Relevance From 2007 through 2015, the volume of primary prevention implantable cardioverter-defibrillators and the proportion of devices not meeting the Centers for Medicare & Medicaid Services National Coverage Determination criteria decreased at all hospitals with substantially larger decreases at hospitals that reached settlements in the US Department of Justice investigation. These patterns extended to implantable cardioverter-defibrillators placed in non–Medicare beneficiaries, which were not the focus of the US Department of Justice investigation