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New Medical Devices: Invention, Development, and Use (1988)

Chapter: Federal Support of Medical Device Innovation

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Suggested Citation:"Federal Support of Medical Device Innovation." National Academy of Engineering and Institute of Medicine. 1988. New Medical Devices: Invention, Development, and Use. Washington, DC: The National Academies Press. doi: 10.17226/1099.
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Suggested Citation:"Federal Support of Medical Device Innovation." National Academy of Engineering and Institute of Medicine. 1988. New Medical Devices: Invention, Development, and Use. Washington, DC: The National Academies Press. doi: 10.17226/1099.
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Suggested Citation:"Federal Support of Medical Device Innovation." National Academy of Engineering and Institute of Medicine. 1988. New Medical Devices: Invention, Development, and Use. Washington, DC: The National Academies Press. doi: 10.17226/1099.
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Suggested Citation:"Federal Support of Medical Device Innovation." National Academy of Engineering and Institute of Medicine. 1988. New Medical Devices: Invention, Development, and Use. Washington, DC: The National Academies Press. doi: 10.17226/1099.
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Suggested Citation:"Federal Support of Medical Device Innovation." National Academy of Engineering and Institute of Medicine. 1988. New Medical Devices: Invention, Development, and Use. Washington, DC: The National Academies Press. doi: 10.17226/1099.
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Suggested Citation:"Federal Support of Medical Device Innovation." National Academy of Engineering and Institute of Medicine. 1988. New Medical Devices: Invention, Development, and Use. Washington, DC: The National Academies Press. doi: 10.17226/1099.
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Suggested Citation:"Federal Support of Medical Device Innovation." National Academy of Engineering and Institute of Medicine. 1988. New Medical Devices: Invention, Development, and Use. Washington, DC: The National Academies Press. doi: 10.17226/1099.
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Suggested Citation:"Federal Support of Medical Device Innovation." National Academy of Engineering and Institute of Medicine. 1988. New Medical Devices: Invention, Development, and Use. Washington, DC: The National Academies Press. doi: 10.17226/1099.
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Suggested Citation:"Federal Support of Medical Device Innovation." National Academy of Engineering and Institute of Medicine. 1988. New Medical Devices: Invention, Development, and Use. Washington, DC: The National Academies Press. doi: 10.17226/1099.
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Suggested Citation:"Federal Support of Medical Device Innovation." National Academy of Engineering and Institute of Medicine. 1988. New Medical Devices: Invention, Development, and Use. Washington, DC: The National Academies Press. doi: 10.17226/1099.
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Suggested Citation:"Federal Support of Medical Device Innovation." National Academy of Engineering and Institute of Medicine. 1988. New Medical Devices: Invention, Development, and Use. Washington, DC: The National Academies Press. doi: 10.17226/1099.
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Federal Support of Medical Device Innovation LEO J. THOMAS, JR. Every year, more than 80,000 Americans suffer permanently dis- abling but nonfatal injuries to the brain or spinal column. Many victims are young, just beginning their lives, and have much to offer society. It is estimated that direct and indirect costs of each of these disabling injuries is at least $100,000. The total cost to society adds up to an estimated $75 billion to $100 billion a year. Reducing the costs of individuals disabled by injury is but one way that medical device innovation can benefit society. Development of new medical devices also offers hope to individuals suffering from arthritis, emphysema, heart disease, cancer, blindness, deafness, kidney malfunction, back pain, sleeping disorders, and a host of other health-related conditions. Support for such innovation is in part a function of the partnership between private enterprise and the federal government, where each funds areas of research it is best qualified to support. Development of new medical devices depends on the broad base of biomedical knowl- edge—most of which is developed by public funds. In 1986 the Commission on Engineering and Technical Systems of the National Research Council ordered a study to evaluate the state of engineering research in the United States. One of the seven areas studied was bioengineering. In its final report (National Research Council, 1987, p. 88) the Bio- engineering Research Panel highlighted eight areas in biomedicine that would benefit from further research. The areas are (1) systems phys- iology and modeling, (2) neural prostheses for human rehabilitation, 51

52 CURRENT TRENDS (3) biomechanics, (4) biomaterials, (5) biosensors, (6) metabolic im- aging, (7) minimally invasive procedures, and (8) artificial organs. In several areas the application is already commercially attractive and some of the research support will come from private industry. In other areas, more basic knowledge needs to accumulate before commercial investment is likely. These areas would particularly benefit from public support of research. SYSTE MS PHYSIOLOGY AND M ODELIN G Research in systems physiology and modeling derives from the modern engineer's need to describe complex systems by mathematical models. Such models can provide insight into the behavior of the system and can lead to experimentation that enhances our understand- ing of the system. Living organisms are extremely complex systems. For example, a mature red blood cell performs some 2,000 biochemical reactions. And this is less complex than cells that are growing or dividing or cells that perform excretory or contracting functions. Integrating knowledge from cell biology, biochemistry, and physiology enables us to under- stand the living organism as a complex system and to predict the impact of man-made devices and remedies on the system. Knowledge of physiology, particularly as expressed in models, has wide application in bioengineering. For example, Robert W. Mann has been conducting research on the human hip joint for several years. He has found that, although reported frictional coefficients in synovial joints are very low, a computer model of the human hip joint in sim- ulated walking predicted a temperature rise within the joint of several degrees Celsius (Tepic et al., 1984~. Dr. Mann confirmed this prediction with physical experiments on intact human hips dynamically loaded and articulated as in walking (Tepic et al., 1985), and demonstrated that heat shock proteins can be induced by the temperature increases predicted by the model (Madreperla et al., 1985~. Recently, Dr. Mann published the results of in viva pressure measurements in the human hip joint (Hodge et al., 1986~. A pressure- instrumented hip prosthesis monitored the pressure at 10 locations within the joint socket 253 times a second as the patient walked Results of such research help us understand initiation and progression of degenerative joint disease. This research has important implications for development of future prosthetic devices and for slowing or preventing the course of disease and thus for the several million people in the United States alone who suffer from degenerative hip disorders such as arthritis or avascular neurosis. Interestingly, support for Dr.

FEDE~L SUPPORT OF MEDICAL DEVICE INNOVATION 53 Mann's research did not come from the National Science Foundation (NSF) or the National Institutes of Health (NIH); it came mostly from the Department of Education. NEURAL PROSTHESES FOR HUMAN REHABILITATION The development of neural prostheses for human rehabilitation holds promise for victims of trauma, congenital defects, and acquired diseases such as cancer. More than 12 percent of Americans have some degree of physical disability, and each year more than 80,000 Americans sustain permanently disabling but nonfatal injuries to the brain or spinal column. A new class of neural prostheses using integrated circuits is now in the early stages of development. Coupled with stable, biocompatible electrodes, these circuits can connect directly to the central and peripheral nervous systems. Inventions involving these devices, such as ear implants to bring sound to the neurologically deaf, offer great promise for improving the quality of life for some disabled individuals. We are already seeing evidence that functional movement and bladder control can be restored to those who have suffered a stroke or spinal cord injury. In the future, we can anticipate development of devices that will give the blind a semblance of vision through electrical stimulation of the occipital center of the brain. We may even be able to restore functional movement and bladder control to those who have suffered a stroke or spinal cord injury. BIOMECHANICS Biomechanics deals with the response of living matter to physical forces. Such research has value in explaining and reducing both trauma as occurs in accidents and sports and long-term deteriora- tion which causes low back pain and osteoarthritis. Biomechanics research can lead to the prevention of injuries. Injuries are the fourth leading cause of death in the United States and the leading cause of death for people age 1 through 44. In 1983 the National Center for Health Statistics estimated that there are 4.1 million preretirement years of life lost because of injuries in the United States per year. By contrast, 1.7 million years were lost to cancer and 2.1 million years to heart disease and stroke. However, only $112 million was spent for research on injury, whereas $998 million went to cancer research and $624 million to research on heart disease and stroke (National Research Council and Institute of Medicine, 19851. Injury in America: A Continuing Public Health Problem, published

54 CURRENT TRENDS in 1985 by the Institute of Medicine and the Committee on Trauma Research, Commission on Life Sciences, National Research Council (National Research Council and Institute of Medicine, 1985), suggests that the first step in understanding injury biomechanics is to understand how injuries occur. Yet, for most injuries this information is not available. Research is needed on the measurement of biomechanical responses, prevention of second injury to an injured area, determination of human tolerances to impact, and assessment of safety technology. A thorough understanding of the neuromuscular control system will lead to improved artificial limbs and robotics, and perhaps to ambu- latory systems for those disabled by injury. Biomechanics research, through an improved understanding of the interaction between blood flow and blood vessel walls, can help reduce the incidence of heart disease, atherosclerosis, and stroke—the leading causes of death in the United States. Research on the biomechanics of the spinal column may help prevent certain types of back pain, studies of stresses in the lung can be used to treat emphysema victims, and biomechanics research on joints may help reduce arthritis joint degradation or assist in the development of permanent joint replacements. BIOMATERIALS Another priority for biomedical research is in the area of biomaterials. New opportunities to synthesize materials derive from the availability of polymers and macromolecules that, in addition to having specific engineering properties, can be designed to be compatible with the human body. For example, biomedical engineers are conducting basic research on the interactions between biological molecules and cells in various environments. Because of the complexity of the interactions, however, much basic research is still needed. BIOSENSORS Biosensors are devices that convert biological information into an electronic signal that can be used for diagnosis or therapy. Research on biosensors leads to earlier disease detection and helps scientists better understand the body's natural sensors and actuators. Micro- machining technology adapted from the microelectronics industry can lead to the development of smaller, more reliable, and more repro- ducible sensors. Chemical sensors suitable for use in laboratory and in viva monitoring also require further research.

FEDERAL SUPPORT OF MEDICAL DEVICE INNOVATION 55 Research is necessary to make biosensors compatible with the human body and with signal processing systems. The goal is to produce minimally invasive sensors that permit diagnostic and therapeutic monitoring of a patient. The monitoring could be done at the patient's home and the information sent electronically to a hospital computer ~ . for review. METABOLIC IMAGING Metabolic imaging offers safe, powerful ways to see inside the body and includes such techniques as positron emission tomography (PET), magnetic resonance imaging (MRI), x-ray computed tomography, and ultrasound. In addition to physical information, biochemical informa- tion about natural substances and metabolites can now be obtained by some of these techniques. This field is highly dependent upon basic research on the physical and biochemical properties of body tissues and on integrative systems analysis. MRI offers a good example of how federal funding for medical device innovation has affected the evolution of a technology and influenced the development of a medical device industry. In the early 1970s it was recognized that MRI could provide advantages over ionizing radiation by using radiowaves and powerful magnetic fields. It had the additional potential of providing excellent soft tissue contrast. These advantages would lead to the earlier detection of diseases and noninvasive, accurate pathologic diagnoses. Balancing the potential advantages were some real barriers, including the high cost of magnetic resonance imagers and the difficult logistics of installation. MRI also required more physician time than alternative metabolic imagers, and its efficacy in clinical medicine compared to other imagers was unclear. In this ambiguous situation, federal support of innovation in MRI was particularly important. For more than a decade, NIH supported research on MRI, biomedical application of MRI parameters, and biomedical application of magnetic resonance spectroscopy. For sev- eral years NIH had an active intramural program of research support for MRI applications. In addition, the National Cancer Institute funded programs to explore the use of MRI in studying the metabolism of normal and malignant cells and the effects of drugs on cell metabolism. The National Heart, Lung, and Blood Institute also funded several MRI-related extramural grants. In addition, the National Science Foundation supported a pioneering research effort on MRI at the University of California, Berkeley. The effect of all this federal support over the decade of the 1970s

56 CURRENT TRENDS was to provide a foundation that permitted industry to fund research on MRI applications. Today MRI is well accepted in the medical industry. Several manufacturers offer the machine for sale on a routine basis, ways are being found to cut the time required to produce an image, and costs are being managed so that MRI provides a good value for many situations. MINIMALLY INVASIVE PROCEDURES Minimally invasive procedures either replace or preclude the need for major surgery. For example, treatment for obstructed arteries usually involves open heart surgery and replacement of the obstructed arteries with segments of veins transplanted from other parts of the body. A relatively new alternative to surgery is percutaneous transluminal coronary angioplasty. In this minimally invasive procedure, a catheter is threaded into the restricted vessel from an artery in the leg or arm and a small balloon at the end of the catheter is gently inflated to eliminate blockage without weakening or tearing the vessel. Angioplasty is an excellent example of a new technology with social and economic benefits. It not only reduces discomfort and recovery time for patients but it is also less expensive. At present, approximately 250,000 cardiac bypasses are performed annually. At a cost of about $16,000 each, the total annual cost exceeds $4 billion (National Research Council, 1987, p. 9S). Angioplasty costs about half that amount, and other minimally invasive procedures carry similar savings. Angioplasty was developed with private funding by industry and is an example of the benefits that can accrue when private industry can justify the cost of research and development. In this case, there was a clear market for the catheters used in the procedure. That market amounted to $4 million in the early 1980s; in 1986 it had grown to $175 million, and is expected to reach $490 million in 1991. It is important to keep in mind, however, that angioplasty would not have been developed if imaging techniques had not been available to permit the physician to see and maneuver the catheter. We therefore find that advances in one medical technology may lead to advances in others. Today, for example, the medical practitioner can perform percutaneous transluminal coronary angioplasty and other procedures such as lithotrypsy because relatively low-strength radiation can be used to see inside the human body.

FEDE~L SUPPORT OF MEDICAL DEVICE INNOVATION ARTIFICIAL ORGANS 57 The final area of biomedical research emphasized by the Bioengi- neering Research Panel is artificial organs. Replacement of organs is in its infancy, and transplants and synthetic organs currently have limited effectiveness. The artificial heart program is exceedingly ex- pensive, but other artificial organs—such as implanted insulin-produc- ing cells for diabetics—may be less costly. In the future, multidisci- plinary efforts combining biochemical and biomedical engineering should lead to synthetic systems capable of replacing natural, multi- functional organs in human beings. As these new technologies develop, careful attention needs to be paid to the costs and benefits associated with introduction of new technologies and new medical devices. Such attention will encourage the effective and efficient use of new medical technologies and discourage costly and wasteful practices. The enormous potential social benefit that would result from im- proving patient care and quality of life through research and devel- opment in these eight areas of bioengineering research is obvious. But there are also secondary social benefits the potential of new tech- nologies to improve the economic strength of the nation by creating jobs and having a favorable impact on the balance of trade. Many of these new medical technologies may at first seem expensive, but productivity improvements can be foreseen. For example, a report of the Office of Technology Assessment (U.S. Congress, Office of Technology Assessment, 1984, p. 32) recalls that "in the mid-1950s and 1960s . . . a medical technologist could test a patient's blood for excess glucose manually, accomplishing six tests per hour. By 1983 one medical technologist, supervising the work of one machine, could turn out 1,800 individual tests per hour. But there was virtually no capital equipment in the mid-19SOs instance, and about $400,000 in capital equipment in the 1983 case." And the process is continuing: Inexpensive devices have recently become available that permit dia- betics to monitor their glucose levels at home, adjusting their therapy according to the results. FEDERAL SUPPORT FOR BIOMEDICAL ENGINEERING RESEARCH The effectiveness of steady, concentrated federal funding in devel- oping medical technologies is illustrated by the roles of the National Institutes of Health, the Veterans Administration, and the Public Health Service in supporting the development of dialysis techniques for use in treating end-stage renal disease (ESRD), or kidney failure.

58 CURRENT TRENDS NIH funded early research on maintenance dialysis and on trans- plantation of kidneys. Annual funding for research on kidney and urinary tract disease at NIH increased from $47 million in 1976 to $90 million in 1982. These funds contributed significantly to the develop- ment of hollow-fiber dialyzers, the efficient enhancement of flat-plate dialyzers, the introduction of "single-needle" dialyzers, the determi- nation of dietary protein levels for dialysis patients, the establishment of a national registry of patients on dialysis, the development of absorbents for uremic wastes, the development of a portable artificial kidney, the prevention and treatment of chronic bone pain and bone fractures in patients, the treatment of chronic anemia in patients, and the development of the concept of hemofiltration. Other federal policies were also crucial to the development of dialysis technology. In the early 1970s, the federal government decided that dialysis would be reimbursed by government medical programs. With this assurance, and the foundation provided by publicly funded re- search, private funding of dialysis research increased and devices for this market were developed. Before that assurance, manufacturers had considered this an orphan device fieldstone with insufficient market potential to justify the private expense of developing products. Today, kidney dialysis is a thriving business. At present, U.S. support for fundamental research in biomedical engineering is relatively small and scattered throughout the federal government. Because biomedical engineering is a multidisciplinary activity, it does not often conform to traditional boundaries of policy issues and research programs. Biomedical engineering, therefore, may lack the organizational focus that oncology, for example, finds in the National Cancer Institute. Federal support for biomedical engineering research is spread across a number of agencies: the National Science Foundation, the National Institutes of Health, the National Bureau of Standards, the Departments of Energy (DOE) and Education, and the Veterans Administration, among others. In addition, support for biomedical engineering research frequently is spread among different units within agencies. It is difficult to find reliable estimates for federal expenditures supporting biomedical engineering research. For example, the NSF Engineering Directorate funded programs in biochemical and biomass engineering research, biotechnology, and aid to the handicapped at a combined $9.4 million in fiscal year 1985. In addition, NSF provided funds for bioengineering research through its Industry-University Cooperative Research Project. NSF support for biochemical and biomedical engineering may have totaled $12 million in fiscal year

FEDERAL SUPPORT OF MEDICAL DEVICE INNOVATION 59 1985. The biomedical engineering portion of this $12 million, however, was relatively small. An analysis of NIH, NSF, and DOE grants active in early 1983 indicated that funds totaling nearly $50 million supported research on diagnostic imaging. This support was scattered through various insti- tutes and agencies and covered a wide variety of subjects. The National Institutes of Health, the principal agency of the U.S. government for support of biomedical research, has an overall budget of $5.5 billion per year. This research investment provides a rich source of new scientific knowledge that creates opportunities for the development of new medical devices. However, investment in the fundamental areas of biomedical engineering constitutes only about 1 percent of the NIH budget. At NIH, few engineers are represented on groups that award extramural grants. NIH's Intramural Research Program funds $660 million of research by in-house investigators each year; only $1 1 million of this budget goes to the Biomedical Engineering and Instrumentation Branch. Less than 5 percent of the 5,000 people with advanced degrees who conduct research at NIH are bioengineers or are from a bioengineering-related discipline. Because of increased competition for limited research resources, government agencies involved in biomedical engineering research have begun to shift from a philosophy in which research grants were seen as instruments for investment to one in which grants are considered a means to procure a product. Such research may not be best accom- plished in government and university laboratories, and a promising alternative has been developed. In the early 1980s, the federal govern- ment established the Small Business Innovation Research (SBIR) program. In fiscal year 1983, NIH expended $7.3 million in the SBIR program. An analysis conducted by the Office of Technology Assess- ment showed that approximately 40 percent of NIH's Small Business Innovation Research awards supported medical device applications (U.S. Congress, Office of Technology Assessment, 1984, p. 861. High-risk bioengineering research projects fundamental research that may significantly benefit society but carries a large risk of failure- are important, but such projects are not often funded by federal agencies. One way to remedy this is for each agency to earmark funds for high-risk research. The NSF has already established such a program. Alternatively, awards can be given to investigators based on their research histories. Such awards may provide successful researchers with the opportunity to conduct high-risk research. Federal funding of biomedical engineering research also supports education and training of young biomedical engineers. Over the past

60 CURRENT TRENDS decade, biomedical engineering students have represented less than 2 percent of all engineering students in both master's and doctoral degree programs. During this time, there has been a decline in the number of doctoral students and an increase in the number of students enrolled in terminal master's degree programs in biomedical engineering. The decline of Ph.D. students may reflect a loss of students to medical schools or other fields that have better research funding. There is a clear need to train more young Ph.D.-level engineers who understand the major principles of biology, medicine, and other relevant scientific disciplines. Advanced-degree engineering students may not be choosing biomed- ical engineering because career opportunities are unclear. As public and private support of research and development in biomedical engi- neering becomes stronger, career opportunities would become evident, bringing talented students into the field. CONCLUSION Numerous research opportunities exist in at least eight biomedical engineering fields, promising significant social and economic benefits. But private industry will do only part of the necessary work. Federal support for basic Bioengineering research must continue to provide a knowledge base that medical device manufacturers can use to make decisions about developing and marketing new technologies. Federal support for Bioengineering research is scattered among agencies, insufficient to fund many worthwhile projects, and not well coordinated. A mechanism should be created to review and coordinate federal programs which support Bioengineering research. The Bioen- gineering Research Panel recently recommended that coordination of research programs in biomedical engineering could be improved through creation of an interagency body that has the support of senior administrators in each participating agency (National Research Council, 1987, p. 109). It may also be worthwhile for NIH to establish an interdisciplinary center for biomedical research that would be similar in concept to the NSF's Engineering Research Centers. The Bioengineering Research Panel also recommended that individuals who rank grant proposals and award research funds in NIH and NSF consider funding projects that, although they have great potential for significant results, might also have a high risk of failure. Finally, the Bioengineering Research Panel suggested that there be a permanent advisory body to assess biomedical engineering research

FEDERAL SUPPORT OF MEDICAL DEVICE INNOVATION 61 opportunities and needs, review relevant agency projects, and identify new and changing program Leeds. In closing, I would like to remind readers not to lose sight of the great commercial potential in biomedical engineering. The overall U.S. market for biomedical engineering devices and systems in 1987 is estimated to be over $20 billion, and parts of that market are growing at annual rates ranging from 10 to 25 percent. New opportunities in the eight areas of biomedical engineering could add considerably to that market. For the sake of basic research that could alleviate human suffering and reduce the costs of medical care, and for the potentially large commercial markets for products resulting from such research, I hope to see increased cooperation among federal agencies funding basic bioengineer~ng research and between those agencies and the medical devices industry. REFERENCES Hodge, W. A., R. S. Fijan, K. L. Carlson, R. G. Burgess, W. H. Harris, and R. W. Mann. 1986. Contact pressures in the human hip joint measured in viva. Proceedings of the National Academy of Sciences USA 83(May):2879-2883. Madreperla, S. A., B. Louwerenburg, R. W. Mann, C. A. Towle, H. J. Mankin, and B. V. Treadwell. 1985. Induction of heat-shock protein synthesis in chondrocytes at physiological temperatures. Journal of Orthopaedic Research 3:3~35. National Research Council. 1987. Directions in Engineering Research: An Assessment of Opportunities and Needs. Engineering Research Board. Washington, D.C.: National Academy Press. National Research Council and Institute of Medicine. 1985. Injury in America: A Continuing Public Health Problem. Committee on Trauma Research, Commission on Life Sciences. Washington, D.C.: National Academy Press. Tepic, S., T. Macirowski, and R. W. Mann. 1984. Simulation of mechanical factors in human hip articular cartilage during walking. Pp. 834-839 in Summer Computer Simulation Conference, Boston, Mass., July 2~27, 1984. La Jolla, Calif.: Society for Computer Simulation. Tepic, S., T. Macirowski, and R. W. Mann. 1985. Experimental temperature rise in human hip joint in vitro in simulated walking. Journal of Orthopaedic Research 3:51 520. U.S. Congress, Office of Technology Assessment. 1984. Federal Policies and the Medical Device Industry OTA-H-229 (October). Washington, D.C.

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In the past 50 years the development of a wide range of medical devices has improved the quality of people's lives and revolutionized the prevention and treatment of disease, but it also has contributed to the high cost of health care. Issues that shape the invention of new medical devices and affect their introduction and use are explored in this volume. The authors examine the role of federal support, the decision-making process behind private funding, the need for reforms in regulation and product liability, the effects of the medical payment system, and other critical topics relevant to the development of new devices.

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