The rising costs of health care and interest in the evaluation of health services and systems have sparked an increased need for technology assessment. A variety of available methods of assessment are described in the Institute of Medicine's book Assessing Medical Technologies (1). Although such methods as the randomized controlled trial (RCT) are widely accepted and used, obtaining information by such methods often takes a considerable amount of time, expense, and sophistication in study design. These costs suggest that a broader range of methods for collecting information about health care technologies should be considered. A vast resource of data collected on patients, ranging from a provider's practice records to national data sets, might be useful for technology assessment if it could be properly appraised.

A search of literature using the Connecticut Tumor Registry (CTR) for technology assessment produced eight articles. These articles represent a small but apparently increasing percentage (2%) of total CTR publications. By keeping pace with the development and dissemination of medical technologies, the population-based CTR has been useful for assessing them, especially their adverse effects.

The Surveillance, Epidemiology, and End Results (SEER) cancer registry contributed to technology assessment by providing population-based samples for detailed case-control studies, by serving as the control group in comparisons with various experimental groups, by allowing an assessment of selection bias in clinical trials, and by facilitating evaluations of classification and coding systems.

This review of publications based on data from the Veterans Affairs Normative Aging Study identified four articles that were considered assessments of health care technologies. Three evaluated methods for research on body composition, the fourth studied ventricular size in patients with presenile dementia. Several additional articles are discussed that provided data on baseline values or risk factors for disease that might be useful in generating hypotheses to be tested in later assessments of technologies.

Of the 52 studies emanating from the Veterans Affairs Dental Longitudinal Study, 6 were identified as technology assessments. Three of these studies evaluated dental radiographs used for the diagnosis of oral lesions. Two studies compared alternative technologies for the replacement of missing teeth, and one reported the effects of NSAIDs on alveolar bone loss. Four additional articles are discussed that provide data that will be useful in future assessments of dental technologies.

To assess the role of observational data bases in technology assessment, we examined 26 articles from the Framingham Heart Study that evaluated a technology, therapy, or predictive instrument. These assessments were grouped into four categories: (a) the study of a technology voluntarily in use by the cohort, (b) the application of an external technology to members of the cohort, (c) the use of the Framingham results to evaluate an unrelated assessment, and (d) the use of the results to validate predictive instruments from other studies. Factors that contribute to the ability of the study to assess voluntary and external technologies include long-term follow-up, a stable cohort, and storage of such nonnumeric data as cardiograms and blood samples. Framingham results have been used to determine outcome measures in later studies. Although the Framingham Study was not designed to assess a technology, we found that large-scale, observational data bases can and do contribute to technology assessment.

The majority of the 26 technology assessment articles from the Coronary Artery Surgery Study (CASS) follow the original purpose of the registry and evaluate the therapeutic capabilities of coronary artery bypass graft surgery. However, these registry data have also been used to identify risk factors for cardiovascular disease, to test diagnostic technologies, and to evaluate technological processes. Consideration of quality of life issues and the availability of cost data provide valuable additions to the continued use of the CASS for technology assessment.

We reviewed the 18 disease-specific evaluations that used the data base of the International Bone Marrow Transplant Registry to determine the effectiveness of alternative strategies for bone marrow transplant. We identify 17 treatment variables that physicians can control and report the associations between these variables and five clinical endpoints: stable engraftment, graft-versus-host disease, development of interstitial pneumonia, relapse, and disease-free survival. We also suggest policies to promote active participation in establishing and operating a registry.

In this concluding article, we summarize the major ways that seven registries and data sets have been used for technology assessment in the published literature. The registries fell into three groups according to the original purpose of the registry. Within each group, we note the types of contributions that researchers using the registries made to technology assessment.

This study assesses the nature, use, and quality of large administrative data bases available in different countries for technology assessment in health care. Using postal questionnaires, data were collected describing 91 data bases from 15 countries. Current uses are promising, but more efforts are needed if the full potential of administrative data files is to be tapped.

An economic evaluation was undertaken concurrently with a randomized trial comparing a Caregiver Support Program (CSP) with existing conventional community nursing care for those caring for elderly relatives at home. The differences in resource consumption were compared with changes in caregiver quality of life, as measured by the Caregiver Quality of Life Instrument (CQLI). A 20% difference from baseline in the CQLI favored the experimental (CSP) group, although this did not reach conventional levels of statistical significance. A comparison of improvement in quality of life with costs implies an incremental cost per quality-adjusted life year gained of Canadian $20,000 for the CSP, which compares favorably with other health care interventions. Further, larger studies are required to confirm this result.

The present study compares the cost of antitumor therapy and adverse cardiovascular effects during the first year of treatment with oral estrogens, nonoral estrogens, or surgical castration in patients with prostatic cancer. We found a much higher cost for patients treated with orchidectomy and oral estrogens than for patients treated with nonoral estrogens. Twenty-five percent of the patients treated with oral estrogen suffered cardiovascular complications, compared to none of the patients treated by orchidectomy or nonoral estrogens. The initial cost of orchidectomy as compared to nonoral estrogen treatment was shown not to be balanced within the expected survival time of patients with advanced prostatic cancer. Furthermore, surgical castration causes psychological trauma to the patient. We recommend parenteral estrogen therapy as a low-cost therapeutic regimen in patients with prostatic cancer.

Statistical analyses that involve regression methods often encounter data in which some observations have substantial influence. This article presents a nontechnical discussion of influence and of two techniques, based on leaving out each individual observation in turn, for diagnosing influential data. An example illustrates the techniques in an analysis of recurrence rates in endoscopic treatment of bleeding peptic ulcers.