The cost-effectiveness of a medical intervention at the population level may deviate from that reported for evaluations at the patient level. It is important for researchers and decision makers to know about the relevance of externalities, phasing-in effects, treatment effectiveness in the community, capacity issues, and different time perspectives in the evaluation of an intervention.

A model for quality assessment of heart transplantation that combines a scientific method for studying the recipients' quality of life and a basis for a method of clinical work by nurses and other health care professionals is discussed. Besides its use as a research method, this model also may serve as an instrument for documenting patients' biopsychosocial status, including coping capacity, and for evaluating nursing interventions.

In less than four years, the techniques of gene transfer have been taken from the laboratory and translated into numerous clinical trials. Although gene therapy was initially designed for the molecular repair of monogenic deficiency diseases, most of the current studies of gene therapy are targeting cancer.

Adaptive immunity requires both specific recognition of an antigen and its translation into appropriate lymphocyte responses. This paper reviews the striking differences in B- and T-lymphocyte antigen recognition, details the pathways for conversion of protein antigens into peptide–major histocompatibility complex molecule ligands for T-cell receptors, and summarizes the roles of costimulatory signals in lymphocyte activation. This information is used to suggest new approaches for the rational design of vaccines.

It is now established that the mucosal immune system is a separate entity and is regulated in a different fashion than that in peripheral lymphoid tissues (the systemic immune system). In this brief review, five selected areas within the field of mucosal immunity are discussed in the context of the goals for vaccines for the Children's Vaccine Initiative.

The influences of four principal types of decision makers on the acquisition of magnetic resonance imagers were measured in hospitals in Southern California, Oregon, and Washington. We propose that of the decision makers assessed, physicians had the most influence on the acquisition of magnetic resonance imagers.

We determined the distribution and sophistication of obstetric technologies in all 80 maternity hospitals in the state of Washington and examined the effect of rural or urban location, birth volume, and physician staffing on technological intensity. Although smaller and more rural hospitals refer most premature and low-birth-weight infants to regional referral centers, sophisticated prenatal and intrapartum technologies are available in the majority of even the smallest and most remote rural units. Rural hospitals have slightly lower obstetrical intervention rates than do their urban counterparts, but the differences are not great.

This paper presents the framework for a one-semester course to give physicians a better understanding of the core concepts of technology assessment, using medical instrumentation technology as a vehicle to stimulate the discussion of technology assessment and its applications. An assessment matrix has been developed as an organizational tool to identify issues in assessment to be addressed under each topic and to identify those issues that are of key importance to particular technologies. At the end of the class, the physician-student should be able to identify major types of medical instrumentation and the instrument's principal application(s), to identify the techniques of technology assessment, and to analyze the economic, ethical, and legal issues that are applicable to instrumentation.

This pilot study is the first known attempt to test the willingness-to-pay or willingness-to-accept (WTP/WTA) method of assessment on a community-based primary prevention program against cardiovas cular disease. The results indicate that the population's perceived WTA outweighs the program's costs by at least three to one. However, the methodological problems of using the WTP/WTA method in community-based programs are far from solved, and further research in this area is required.

The costs included in economic evaluations of health care vary from study to study. Based on the theory of cost-benefit analysis, the costs that should be included in an economic evaluation are those not already included in the measurement of willingness to pay (net willingness to pay above any treatment costs paid by the individual) in a cost-benefit analysis or in the easurement of effectiveness in a cost-effectiveness analysis. These costs can be defined as the onsumption externality of the treatment (the change in production minus consumption for those included in the treatment program). For a full economic evaluation, the consequences for those included in the treatment program and a caring externality (altruism) should also be added.

Adjuvants increase cell-mediated and humoral immune responses to specific antigens. Used with recombinant viral antigens, they can elicit the production of T lymphocytes that lyse target cells, expressing the antigen in a genetically restricted fashion. Adjuvants can augment the production of interferon-gamma, thereby favoring the production of protective antibody isotopes, such as immuno-globulin G2a in the mouse. Modern adjuvants display the efficacy of Freund's complete adjuvant without its side effects. One such adjuvant is Syntex adjuvant formulation, a synthetic analogue of muramyl dipeptide in a microfluidized squalane/squalene-in-water emulsion. Monophosphoryl lipid A in a similar lipid emulsion is also effective. Immune-stimulating complexes of saponin and antigens elicit potent cell-mediated and humoral responses. A purified saponin component has adjuvant activity with reduced side effects; liposomes also can have adjuvant activity. Administering antigens in adjuvants can overcome low responsiveness in very young and old experimental animals and in those that are genetically low responders. Adjuvants are likely components of a new generation of recombinant and subunit vaccines.

The costs and benefits of vaccinating troops on United Nations tours in Yugoslavia against hepatitis A were compared. The marginal cost of one case of hepatitis A avoided by vaccination was calculated and compared with the marginal cost of achieving the same outcome by passive immunization. The cost-benefit ratio (medium estimate) for troops at low risk of contracting hepatitis A was 0.01 and for those at high risk was 0.03.

Vaccinating troops against hepatitis A for a single deployment appears to be an inefficient procedure, especially in troops at low risk. However, in professional troops from countries of low hepatitis A endemicity who are likely to be involved in several operational deployments, vaccination becomes more efficient the more times the same troops are deployed.

This study describes the operation of an in-home alarm system in seven Swedish municipalities. Statistics on the diffusion of this technology, its costs, and the characteristics of its use are reported. Alarms were triggered by 60% of the users. Mean annual costs per recipient varied from SEK 1,985 to SEK 8,215, mainly reflecting different patterns of use.

The direct and indirect costs of acute myeloid leukemia were estimated for Sweden in 1989. The calculated total cost was SEK 460 million. Nearly half of the costs, or 1.7 million per patient diagnosed, were indirect costs due to premature mortality. Direct costs of relapses and indirect costs of mortality represent costs due to the absence of completely curable therapy. They also represent potential cost savings that could be ootained after introduction of new treatment options in the future.

Two strategies for vaccine-delivery systems, both relying on concepts of controlled-release technology, are described in this review. The first strategy involves using biodegradable polymer microspheres for parenteral and oral delivery of antigens. The other strategy combines two technologies, the encapsulation of antigen within liposomes and liposome encapsulation in hydrogels, to protect them from a rapid degradation in vivo. Both strategies have shown promise in terms of increasing the immunogenicity of poorly immunogenic peptides and protein vaccines. The microencapsulation process, antigen stability, mechanism of antigen release, and optimal release kinetics for vaccine delivery are reviewed, and the strengths and weaknesses of each approach are discussed.

Several different live attenuated vaccine vectors currently are under development. These vaccines are composed of living viruses or bacteria that are innocuous to the host but can replicate in host tissues and induce immune responses. The genes encoding foreign antigens can be inserted into these vectors to produce multivalent vaccines that promise to induce immunity to more than one target disease after the administration of a single dose of vaccine.

Clinical judgment is increasingly being challenged by the need for randomized clinical trials. The 1987 National Cancer Institute mandate—that the Community Clinical Oncology Program (CCOP) accrue patients to cancer control protocols—provided an opportunity to examine the factors that affect accrual performance. An analysis of 52 CCOPs and their research bases participating in the program found that the availability of protocols, involvement with research base activities, a demonstrated link to community physicians (particularly those physicians, such as surgeons, who had access to patients), and the use of personal contacts to inform non-CCOP physicians about CCOP activities were important facilitating factors for accruing patients to cancer prevention and control trials.

We describe the effects on costs, working patterns, and clinical behavior of installing a DAX “discretionary” biochemistry analyzer. Use of the new analyzer encouraged doctors to be more specific in requesting biochemical tests, which substantially reduced the number of tests requested and slightly reduced overall costs. Doctors preferred being able to order tests in this more specific way.