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LEADERSHIP

Dr. Lee Lucas and analysts Scottie Siewers and Lori Haffner have extensive experience using large claim-based databases to address a variety of research questions. The research team at CORE has collaborated on much of the groundbreaking work done by the Dartmouth Institute of Health Policy and Clinical Practice on regional variations in healthcare utilization and outcomes, including the Dartmouth Atlas of Healthcare. The research team has particular expertise in cardiovascular disease and prevention. Dr. David Clark is an expert on trauma, both in his roles as a trauma surgeon and as an investigator of trauma outcomes. He has served as the Director of the Trauma Services and Trauma and Surgical Care Departments at Maine Medical Center. He has held several leadership positions at the American College of Surgeons and served as the Chairman of the Maine EMS Trauma Advisory Committee. He is a lead faculty at the Harvard Injury Control Research Center at the Harvard School of Public Health.

CARDIOVASCULAR DISEASE

PROJECTS (Current and completed in the past 3 years)

New Cardiac Programs: Patients, Outcomes, Access

Recent years has seen a dramatic increase in the number of hospitals providing coronary artery bypass surgery (CABG) services. However the number of CABG procedures performed is on the decline. Volume is a well established correlate of quality. Although new programs may improve access they may also compromise quality. This ongoing RO1 grant funded by the National Heart, Lung and Blood Institute uses national Medicare claims data over a ten year period to look at the impact of opening new cardiac surgery programs on regions, patients and their outcomes. Specific questions of interest include how new programs gain expertise; by selecting low risk patients, less complicated procedures or by recruiting experienced surgeons. How quickly do new programs behave like long standing programs in terms of volume and patient outcomes? At the population level, what is the impact of new CABG capacity; are new programs located in competitive markets, and are existing rates of CABG redistributed between old and new programs or is there an overall increase in population based rates of CABG? Information about the performance of new programs could inform policy makers, regulators, and hospital administrators as to how to achieve efficient, high quality care and inform patients making the decision about when and where to have their procedure.


Dartmouth Atlas of Cardiovascular Healthcare

CORE collaborated with the Center for the Evaluative Clinical Sciences at Dartmouth Medical School to create a Dartmouth Atlas of Cardiovascular Healthcare, the first specialty specific volume in the Dartmouth Atlas series. Supported by grants from the American College of Cardiology and the Society of Thoracic Surgeons and based on research for the American Federation for Aging Research and the Robert Wood Johnson Foundation, the atlas uses national Medicare data to describe utilization and resource distribution geographically and to highlight specific issues related to quality of care and drivers of demand. The atlas provided a first comprehensive look at outpatient diagnostic testing patterns, drivers of more invasive procedures, surgery and downstream costs. It also developed utilization based measures of the cardiovascular surgery and cardiology workforce, measured capacity through per capita catheterization laboratories, and created a new unit of geography to reflect local catheterization referral patterns. Although the original atlas was based on data from 1996, work is ongoing for an updated atlas using current data and that will be web-published and issue focused.


Open Compared to Endovascular Repair for Abdominal Aortic Aneurysms

As a part of the Dartmouth Atlas Project, CORE assisted in an examination of the impact of the introduction of endovascular abdominal aortic aneurysm (AAA) repair on utilization and outcomes. Using national Medicare claims data, utilization rates of traditional open repair and new endovascular repair were observed revealing substitution by the newer technology and moderate regional variation in overall repair rates. Medicare data are also being used to examine short and long-term morbidity and mortality with open compared to endovascular repair in the ‘real world’ to see if the advantage of the new technology can be seen outside of the clinical trial setting. These analyses will add valuable information about the dissemination and effectiveness in the community setting of a trial proven efficacious treatment.


Documentation of Ischemia Prior to Elective Percutaneous Coronary Intervention

Guidelines call for documenting the extent and severity of ischemia with stress testing to determine the need for percutaneous coronary intervention (PCI) in patients with stable coronary artery disease. Failure to follow guidelines suggests that interventions may be performed that are risky, costly and ineffective.

In collaboration with the University of California, San Francisco and Darmouth-Hitchcock Medical Center, CORE participated in an analysis using national Medicare claims data to assess use of stress testing to document ischemia before performing elective PCI. These important results have clear policy implications for improving the efficient delivery of healthcare.


Pathways to Revascularization

Coronary revascularization is a classic shared decision making problem; for most patients there is no difference in extension of life or prevention of heart attack however there are differences in the control of chest pain. The critical question is at what point on the path from diagnosis to intervention should shared decision-making be supported. Funded by the Foundation for Informed Medical Decision Making, this project uses Medicare claims data to create population based rates of testing and intervention rates as well as perform a cohort analysis to describe the multiple pathways that elderly patients follow on their way to a coronary artery revascularization procedure. By understanding the correlates between testing and intervention and the pathways between diagnosis and treatment, this analysis informs who could benefit from shared decision making and when.


Changes in Utilization of Carotid Revascularization

New approaches for carotid revascularization, including carotid angioplasty and stenting, may augment or supplant traditional carotid endarterectomy. In collaboration with Dartmouth-Hitchcock Medical Center and funded by a grant from the Hitchcock Foundation, CORE assisted in this analysis of utilization patterns for carotid revascularization using national Medicare claims data from 1998-2004. This important analysis sets the stage for understanding whether this new technology is supplanting traditional surgery or being offered to patients who would have been treated medically and what patient factors will allow patients and providers to make informed choices in carotid revascularization.


Testing the Utility of Medicare Claims for Post-Market Surveillance

Obtaining long-term outcomes following placement of high-risk medical devices could be more complete and cost-effective if administrative dataset of medical claims could be used. CORE, in collaboration with Dartmouth and Abbott Vascular Solutions, participated in a pilot study to assess whether Medicare claims can be used for post-marketing surveillance. This project linked the clinical data in the manufacturer’s registry (ARCHeR) of patients who received a carotid artery stent to Medicare claims data to test the ability of the Medicare claims against the gold standard of the registry to identify outcomes of interest.


SELECTED PUBLICATIONS (Since 2000)

TRAUMA AND INJURY

PROJECTS (Current and completed in the past 3 years)

David Clark has been the principal investigator for multiple grant funded projects looking at healthcare delivery among the elderly. Most recently an RO1 grant funded by AHRQ assessed the strengths and limitations of two pre-existing databases; the American College of Surgeons National Trauma Data Bank (NTDB) and the National Inpatient Sample to predict hospital outcomes in injured elderly patients. This project also uses multilevel modeling techniques to estimate and compare hospital performance in the management of injured patients and recommends more informative reporting methods. An RO3 grant also funded by AHRQ applied previously developed modeling methodology to predict hospital length of stay for seriously injured patients using the NTDB.


Prior to that, two R49 projects were funded by the Center for Disease Control (CDC). One was a “major project” subcontract of the Harvard Injury Control Research Center and used Medicare claims data to describe outcomes of elderly patients hospitalized after injury, focusing on regional and inter-hospital variations in factors related to quality of care. The second project implemented newly available software for probabilistic record linkage to combine inpatient, outpatient, ambulance and death certificate data for injured patients in Maine.

SELECTED PUBLICATIONS (since 2000)

HEALTHCARE DELIVERY

PROJECTS (Completed in the past 3 years)

Causes and Consequences of Health Care Intensity

Tremendous regional variation in healthcare utilization and spending are well established. This variation is largely due to differences in intensity; that is, differences in the way similar patients are treated. CORE participated in a 5 year PO1 grant funded by the National Institute of Aging to explore the causes and consequences of regional variation in intensity with the ultimate aim of improving the health and well-being of patients and the financial health of Medicare, and to address health disparities across socioeconomic groups.


CORE participated as the principle investigator and analytic team for a project focused on the causes of variation in intensity using the example of coronary artery disease (CAD). In this analysis, the causes of interest were the factors that drive physician decision making and the consequences of these decisions on intensity. Specifically, using national Medicare claims data we determined what factors, at the patient, physician, hospital and region level, influence physician decision-making in the intensity of initial diagnostic testing and subsequent testing and treatment for CAD. These analyses provide vital information about the forces leading to variations in physician decision making informing policy and clinical interventions to improve equity and clinical effectiveness.


CORE also assisted in the analysis of another project of this P01 which focused on the consequences of regional differences in health care intensity using the detection and treatment of prostate cancer as an example. Specifically, this project used national Medicare claims data to study the impact of increased surveillance intensity on disease specific quality of life measured as treatment free survival. These analyses provide vital information about the potential quality of life impact of more intensive screening and the degree to which patient preference for screening is aligned with care patterns.


Is More Actually Better? The Implications of Increasing Capacity in Health Care

The amount and kind of healthcare used by US residents differs substantially from region to region. Convincing evidence that populations residing in areas of greater capacity receive no significant health benefits from their greater use of services could have important implications for Medicare administration and reform. However the prevailing assumption is that more health care is uniformly beneficial and that variations reflect real difference in health care needs. CORE participated in this RO1 funded by the Robert Wood Johnson Foundation (RWJ) to describe how differences in health system capacity influence the delivery of care and affect outcomes. National Medicare claims data were used to research the hypothesis that greater capacity leads to the treatment of the “marginal patient” (who would not have been diagnosed or treated in a lower capacity system) and will not lead to improved health outcomes.

Benefits of Regionalizing Surgery for Medicare Patients

The long-recognized association between higher procedure volume and lower operative mortality has generated interest in regionalizing high-risk surgical procedures. However, there is concern that regionalization could reduce access and continuity of care. This RO1 grant funded by the Agency for Healthcare Research and Quality (AHRQ) aimed to inform policy makers how patients would be affected by regionalization of high risk surgery. Specifically, this project used national Medicare data to describe the relationship between hospital and surgeon volume and outcome with ten high risk surgical procedures and assessed the implications of alternative approaches to regionalization including requiring minimum volume standards, creating centers of excellence, and restricting regionalization to metropolitan areas.

SELECTED PUBLICATIONS (since 2000)