The diffusion of the computed tomography (CT) scanner in the United States

The Effect of Physician and Hospital Market Structure on Medical Technology Diffusion

OBJECTIVE

To examine the influence of physician and hospital market structures on medical technology diffusion, studying the diffusion of drug-eluting stents (DESs), which became available in April 2003.

DATA SOURCES/STUDY SETTING

Medicare claims linked to physician demographic data from the American Medical Association and to hospital characteristics from the American Hospital Association Survey.

STUDY DESIGN

Retrospective claims data analyses.

DATA COLLECTION/EXTRACTION METHODS

All fee-for-service Medicare beneficiaries who received a percutaneous coronary intervention (PCI) with a cardiac stent in 2003 or 2004. Each PCI record was joined to characteristics on the patient, the procedure, the cardiologist, and the hospital where the PCI was delivered. We accounted for the endogeneity of physician and hospital market structure using exogenous variation in the distances between patient, physician, and hospital locations. We estimated multivariate linear probability models that related the use of a DES in the PCI on market structure while controlling for patient, physician, and hospital characteristics.

PRINCIPAL FINDINGS

DESs diffused faster in markets where cardiology practices faced more competition. Conversely, we found no evidence that the structure of the hospital market mattered.

CONCLUSIONS

Competitive pressure to maintain or expand PCI volume shares compelled cardiologists to adopt DESs more quickly.

The Adoption of Innovations by Provider Organizations in Health Care

Innovations in health care account for some of the most dramatic improvements in population health outcomes in the developed world as well as for a nontrivial proportion of growth in expenditures. Provider organizations are the adopters of many of these innovations, and understanding the factors that inhibit or facilitate their diffusion to and possible disengagement from these organizations is important in addressing cost, quality, and access issues. Given the importance of these issues, the purpose of this article is to (1) create a comprehensive census of studies examining the adoption of and disengagement from innovations in health care provider organizations; (2) organize these studies into an inductively derived classification scheme; (3) assess the studies' strengths and weaknesses; and (4) reflect on the implications of our review for future research.

Evaluation of preoperative model surgery and the use of a maxillary sinus surgical template in sinus floor augmentation surgery

Maxillary sinus augmentation is an accepted technique for dental implant placement in presence of insufficient maxillary bone. There are various techniques in the literature, either by crestal or lateral approach in maxillary sinus augmentation that have high percentage of success, while all have complications. Schneiderian membrane perforation is the most common complication encountered during surgery. The aim of this study was to evaluate the benefits of preoperative model surgery and the ease of use of a maxillary sinus surgical template (MSST) during maxillary sinus augmentation surgery with a lateral approach. Ten patients included in the study needed rehabilitation of a partially or totally edentulous maxilla with an implant-supported fixed prosthesis and requiring sinus augmentation. A questionnaire was asked to performing surgeons, and study results showed the use of an MSST was found to be effective in terms of adaptation (62.5%), window preparation (87.5%), ease of elevation (95.9%), ease of grafting (95.9%), reduction of perforation risk (91.7%), and achieving immobility during the procedure (62.5%); however, the use of an MSST was also found to prolong the surgical procedure (100%) and restrict the view of the surgical area (79.2%). Maxillary sinus augmentation appears to be a useful tool for locating an appropriate entrance to the sinus cavity, allowing for safe elevation of the sinus membrane and effectively grafting the sinus floor.

Time series analysis of use patterns for common invasive technologies in critically ill patients

PURPOSE

Critically ill patients are frequently managed with invasive technologies as part of their medical care. Little is known about use patterns. We examined use trends for invasive technologies used in critically ill patients.

MATERIALS AND METHODS

Using time series analysis and data on 26 989 patients from 3 medical-surgical intensive care units (ICUs) (n = 18 224) and 1 surgical ICU (n = 8765) between January 1, 1999, and January 1, 2007, we measured changes in the proportion of patients receiving the 4 most frequently used invasive technologies used in critically ill patients.

RESULTS

The 4 most common invasive technologies used in critically ill patients during the study period were arterial lines (71%), endotracheal intubations (61%), central venous catheters (51%), and pulmonary artery catheters (18%). The proportion of ICU patients who received pulmonary artery catheters decreased from 25% in 1999 to 8% in 2006 (P < .001). Use of central venous catheters increased from 39% to 46% (P < .001). After adjusting for baseline characteristics, patients admitted in 2006 were 4 times less likely to receive a pulmonary artery catheter (odds ratio, 0.28; 95% confidence interval, 0.24-0.33), but 42% (odds ratio, 1.42; 95% confidence interval, 1.27-1.58) more likely to receive a central venous catheter than patients admitted in 1999. No significant changes were observed for intubations and arterial lines.

CONCLUSIONS

The use of invasive technologies in critically ill patients is changing and may have important implications for resource use, clinician education, and patient care. Initiatives should be considered for ensuring clinician competency during technology transitions.

The Diffusion of New Imaging Technologies: A Molecular Imaging Prospective

Molecular imaging is a complex of technologies that will diffuse into clinical practice over the next 10 to 20 years. Because of characteristics of both the technology and the environment, molecular imaging has the potential to be disruptive to conventional radiology practice. Environmental influences, including scientific and clinical characteristics of the technology, the interests of commercial firms, competition among radiologists and with other specialists, and regulation and reimbursement decision making will influence both the pace of diffusion and the eventual success of various molecular imaging technologies. Molecular imaging poses both threats and exciting opportunities for radiologists. Radiologists must decide how they wish to cope with the advent of molecular imaging, choosing for the present among ignoring its potential, attempting to fit molecular imaging into current practice models, or morphing how they practice to accommodate molecular imaging as a part of radiologic practice.

Managed care and technology adoption in health care: evidence from magnetic resonance imaging

This paper empirically examines the relationship between HMO market share and the diffusion of magnetic resonance imaging (MRI) equipment. Across markets, increases in HMO market share are associated with slower diffusion of MRI into hospitals between 1983 and 1993, and with substantially lower overall MRI availability in the mid- and later 1990s. High managed care areas also had markedly lower rates of MRI procedure use. These results suggest that technology adoption in health care can respond to changes in financial and other incentives associated with managed care, which may have implications for health care costs and patient welfare.

Managed care and technology diffusion: the case of MRI

A growing body of evidence suggests that managed care can reduce overall health care costs but provides little insight into how this could happen. One possibility is that managed care influences the adoption of new medical technologies. In examining the relationship between health maintenance organization (HMO) activity and market-level availability and use of magnetic resonance imaging (MRI), we find that high HMO market share is associated with low levels of MRI availability and use. This suggests that managed care may be able to reduce health care costs by influencing the adoption and use of new medical equipment and technologies.

Comparison of additive and multiplicative models of regional variation in the decline of stroke mortality in the United States

BACKGROUND AND PURPOSE

Although previous studies have shown that geographic variation in the decline of stroke mortality rates may be an important contributor to the changing geographic distribution of stroke mortality in the United States, some concern has been raised that this phenomenon may be model dependent. This study examines the geographic variation in the decline of stroke mortality rates in the United States with the use of both additive and multiplicative models.

METHODS

National Center for Health Statistics and Bureau of the Census data were used to assess regional-level temporal trends of underlying-cause stroke mortality rates in the United States for 1979 through 1989. Both additive and multiplicative models were fit to the data.

RESULTS

Underlying-cause stroke mortality rates have declined fairly steadily in all regions of the United States and for all race-sex groups, although there was significant regional variation in the rate of decline during the period 1979 through 1989. The South, which initially had the highest rates, had the most rapid decline for all race-sex groups when either additive or multiplicative models were used.

CONCLUSIONS

From 1979 through 1989 there was significant geographic variation in the rate of decline of stroke mortality rates, with the most rapid rates of decline in the South. As a result, there has been a decrease in interregional variation in stroke mortality rates.

Diffusion of laparoscopic cholecystectomy in Canada

Patterns of the diffusion of laparoscopic cholecystectomy in Canadian hospitals were determined by a telephone survey of 153 randomly selected hospitals over two years. Results were analyzed by region, hospital size, and type of hospital. Laparoscopic cholecystectomy has diffused very quickly compared with other technologies, before any comprehensive evaluation to consider its potential impact could take place.

Decline in autopsies for deaths attributed to cerebrovascular disease

BACKGROUND AND PURPOSE

United States national autopsy rates have declined in recent years. In the present study, changes in autopsy rates for deaths due to stroke are examined and compared with changes in autopsy rates for all deaths.

METHODS

National Center for Health Statistics data on United States national autopsy rates were examined for the years 1955, 1958, and 1972-1988.

RESULTS

Since at least 1955, nonstroke deaths were more than twice as likely to be autopsied as deaths due to cerebrovascular disease. The annual autopsy frequency for all deaths, for deaths due to stroke, and for deaths due to each stroke subtype declined precipitously after 1972. Since 1982, less than 5 percent of deaths attributed to stroke have been documented by autopsy. Information obtained at autopsy was frequently ignored in the determination of cause of death on the death certificate.

CONCLUSIONS

Careful consideration of the value of autopsy for education, research, and quality assurance is urgently needed. Unless the present problems in obtaining, processing, disseminating, and using autopsy data are adequately addressed, the autopsy rate will continue to decline.

The initial impact of computed tomography on mortality attributed to brain tumor

The exponential growth in the number of computed tomography scanners in the United States between 1975 and 1977 was associated with a transient increase (11.9 and 14.4% for men and women, respectively) in annual crude mortality rates for primary malignant brain tumor from 1976 through 1978. This transient increase in mortality appears to have been an artifactual epiphenomenon associated with the introduction of a new technology.

Technological innovation and the winning-combination phenomenon. The case of the extracorporeal lithotriptor

There are situations where, for many reasons, an innovation considered revolutionary in several respects is widely accepted by those whose ways of doing things are transformed by it. The innovation represents a “winning combination” in that it combines such attractive elements that each party, for its own reasons, will desire its adoption and work toward that common goal. In France, and particularly in the Assistance Publique de Paris and in the Hospices Civils de Lyon, such has been the case with the German-made Dornier extracorporeal lithotriptor, an innovation that makes it possible to destroy kidney stones without surgery.

Substitution of magnetic resonance imaging for computed tomography. An exploratory study

Despite the importance of understanding factors related to physician adoption and use of diagnostic technologies, relatively few studies have been published. Results of a two-year study of the adoption of magnetic resonance imaging (MRI) and its substitution for computed tomography scanning (CT) are presented. The literature on physician adoption and use of technology is used to provide a framework for this study. Differences in adoption and substitution among medical specialties, early versus late adopters, and high versus low users of MRI are examined. Results show that neurologists and internists more rapidly adopt MRI and substitute it for CT than do orthopedists and other surgical specialists. Referral of higher numbers of patients is the best predictor of more rapid substitution. Physicians who were late adopters more quickly substituted MRI for CT. The cost and social implications of empirical versus "ideal" substitution rates are discussed along with how various regulatory, technology assessment, and financial strategies influence substitution. The role of individual physicians, radiologists, and specialty societies in determining substitution rates is also discussed.

The diffusion of magnetic resonance imaging scanners in a changing U.S. health care environment

Technological aspects and early clinical experiences are arousing great enthusiasm over magnetic resonance imaging (MRI). However, influences such as regulation, reimbursement, and increasing competition also are playing important roles in determining the diffusion of this new technology. Of these considerations, competition among providers seems the most important. Competition related to MRI is manifested as direct competition over MRI services, using MRI to improve a provider's strategic position and competition among specialties. In making decisions concerning MRI acquisition and operation, providers are drawing upon their experiences with computed tomography (CT) to help them determine when would be the best time for acquisition, how to decide whether acquisition is appropriate, and how best to acquire, operate, and market the technology.

Medical technology and health expenditure: an economic review and a proposal

This paper is an evaluative survey of the economic literature on the relationship between technology and/or innovation and health expenditures. Various types of analysis viz. econometric modelling; three residual approaches; the cost-of-illness approach; and the literature on supplier interests are contrasted, and the results presented. The paper concludes with a discussion of the policy and planning implications, and a simple, and conventional, proposal is made that could unambiguously determine this relationship in the case of process innovations.

The diffusion of medical technology: a "prisoner's dilemma" trap?

Medical technology diffusion and its effect on the modern hospital and on the rising costs of medical care is an issue which receives considerable attention from economists and policy analysts. In this paper a different approach is used to understand this phenomenon. We present the decision of a single hospital, whether or not to adopt an advanced technology system, using the concept of a noncooperative, nonzero sum game. Such presentation provides us with more insight on the conflict in which hospitals find themselves; the "catch" which pushes them to purchase more and more sophisticated and expensive technology in the hope that they will be able to successfully compete with other hospitals. The situation is further complicated by the existence of another "hidden" player--society, whose goals may differ from those of any individual hospital and even from the collective interests of the hospital sector. Possible conflicts that may exist and suggested solutions for each participant are presented and their policy implication are discussed.

The wide distribution of CT scanners in Japan

Computerized tomography (CT) scanners have been widely distributed throughout Japan since 1975, with the total number reaching 2120 in December 1982. This figure is larger than that of all European countries. Furthermore, the number of CT scanners per million population, Japan exceeds the United States. An investigation to explain the reasons for this rapid increase of CT in Japan with comparisons between Japan and the United States is presented. Uniquely 'Japanese' characteristics may explain the diffusion of CT as follows: the government has no explicit policy to control the adoption of CT. CT has been widely distributed, not only to the large public hospitals, but also, to smaller private hospitals. CT is frequently adopted without assigning additional skilled personnel. Japanese manufacturers have produced low-price CT in addition to developing an active marketing campaign.

Policies toward medical technology: an international review

Rapidly rising medical care costs have become an important political issue in industrialized countries during the past decade. Attempts to control the growth in expenditures have focused on the contribution of medical technology to costs. All industrialized countries have begun to experiment with the kinds of mechanisms necessary to effect changes in development, diffusion, and use of medical technologies. This paper describes government policies toward: 1) research and development, 2) evaluation, 3) safety and efficacy regulation, and 4) investment in and use of medical technologies. To clarify how these policies work in practice, policies toward CT scanners, renal dialysis, and coronary bypass surgery are examined. Rapid changes in policies and laws in different countries are attempts to find effective policy mechanisms, but also reflect the difficulties of choosing a realistic policy objective. Until recently, most countries have focused on promoting the development and adoption of new technologies, or increasing the efficiency of their production and use. A few governments have begun to question and test the benefits of medical technologies as an aid to decision making. Finally, with the growing realization that every kind of care that is beneficial cannot be provided, some countries have begun to consider limiting the diffusion of technologies to a level that strikes a balance between the benefits to be gained and the costs of achieving them.