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Biomedical subjects

S Birch

Publications and source records attributed to S Birch.

At least 73 records · Page 4Linked to original sources
PubMed1993

Guidelines for the adoption of new technologies: a prescription for uncontrolled growth in expenditures and how to avoid the problem.

The guidelines proposed by Laupacis and associates do not stem from economic theory and are a prescription for uncontrolled growth in health care expenditure. In particular, cost-effectiveness ratios provide information relevant to allocation decisions only in very special circumstances that do not usually apply in practice. When two interventions are compared a positive cost-effectiveness ratio (the common case) can tell us, at best, what additional costs will be incurred to generate the additional outcomes. From an economic perspective the information required to determine the attractiveness of a new technology is different: the source of the additional resource requirements must be identified and the opportunity cost of their redeployment estimated. Because the cost-effectiveness ratio (cost/-QALY) is sensitive to the method chosen to calculate QALYs, guidelines that do not specify (or justify) the appropriate method for calculating outcomes are unlikely to produce comparable results (or common yardsticks). In a health care system such as Canada's in which there is always pressure to introduce more effective technology, even if it is more costly, there is a risk of using such noncomparable data to justify adoption of particular technologies. The method of technology evaluation proposed by us is consistent with the stated goal of maximizing the community's health-related well-being for a given level of resources allocated to health care and ensures that new technologies are adopted only if this adoption represents an improvement in resource allocation.

Canada↗
PubMed1993

Equitable access to health care: methodological extensions to the analysis of physician utilization in Canada.

In this paper we analyse the distribution of family physician use in Canada to explore whether the stated goal of reasonable access to care has been achieved. We test hypotheses to see whether (a) variations in incidence and quantity of use are independent of need for care as proxied by self-assessed health status and (b) any observed relationship between variations in use and need is independent of other population characteristics. Previous research has conceptual, statistical and data limitations which bring into question the validity of the findings. These limitations are addressed by using more appropriate data, a conditional model for service utilization and correction for self-selectivity of users in the statistical analysis. Variations in need are identified as important and significant in explaining variations in both incidence and quantity of use with the estimated relationship between use and need being positive. Other population characteristics were found to be important and significant in explaining variations in use although household income is not among them. The relationship between use and need is associated with other variables including education, social support and region of residence. These findings suggest that analyses of utilization based on simple multivariate techniques and aggregate data can produce a picture of utilization that conceals important, policy relevant relationships while revealing other relationships that are essentially artifacts of inappropriate aggregation in ways which provide a false sense of achievement.

Adolescent↗
PubMed1993

Economics, health and health economics: HYEs (healthy-years equivalent) versus QALYs (quality-adjusted live-year)

This paper responds to Culyer and Wagstaff's (CW) and Buckingham's (B) arguments. We refute their claim about the equivalence of HYEs and QALYs; they fail to distinguish between choice under uncertainty and under certainty. CW assume that all individuals have a specific form of utility function, which yields their conclusion of equivalence. B's arguments confuse the measurement technique and the utility theory from which it stems; his argument about the normative superiority of the QALY construct is inconsistent with economic thinking. The HYE, by being compatible with the principles of economics, is superior to the QALY for economic evaluations of health care interventions.

Canada↗
PubMed1993

Searching for a common currency: critical appraisal of the scientific basis underlying European harmonization of the measurement of health related quality of life (EuroQol)

The EuroQol has recently been proposed as a measure of health-related quality of life based on individuals' valuations of health states. The derived values would be used in assessing cost-effectiveness and establishing priorities across a wide range of health-care activities. In this paper we identify some of the limitations of the EuroQol in its role as a particular method for deriving the more generic QALYs. More specifically we explore the implications of using the EuroQol as a measure of individuals' and communities' valuation of health outcomes. We show that the EuroQol suffers from several major limitations and thus cannot be relied upon to provide a valid measure to be used in economic appraisals or studies concerned with establishing priorities as proposed by its proponents. An alternative approach is identified and discussed.

Europe↗
PubMed1993

Ozone exposure inhibits cardiac protein synthesis in the mouse.

Ozone is a major environmental oxidant pollutant. Following ozone inhalation, there are a number of marked pulmonary responses depending on the extent and duration of exposure. Recently it has been established that ozone exposure may also result in cardiac injury. In this study we show that exposure of mice to 800 ppb ozone for as little as 6 h results in a 16% decrease in cardiac protein synthesis rates (p < .02). The fall in protein synthesis is due primarily to a reduced rate of ribosomal efficiency (40%) in the hearts of ozone-exposed mice. This change in cardiac protein metabolism is accompanied by increased levels of two markers of tissue injury: edema and protein carbonyl content. It is unlikely, however, that these observations represent a direct action of ozone on the heart, but rather an indirect effect, possibly mediated by lipid peroxidation products generated in the lung.

Animals↗
PubMed1993

Is reasonable access what we want? Implications of, and challenges to, current Canadian policy on equity in health care.

Considerations of equity in the context of health care systems are often related closely to the presence or level of prices incurred by users of health care services. Some politicians and commentators have suggested that the removal of user charges under the Canadian health care system has led to equal access to care. But it is not clear that the equity principle inferred from these claims corresponds to the equity goals of current Canadian health policy. In this article the authors identify the precise equity principle that lies behind current health policy in Canada and consider the extent to which that principle is reflected in the performance of the system. They then consider other approaches to equity in health care in the context of the stated objectives of Canadian health policy and identify the implications of pursuing reasonable access in future health policy. The authors suggest that the implications of the current equity goals have not been recognized by policy makers, and if they were to be recognized it is not clear that they would be acceptable to Canadian populations and/or policy makers. Moreover, some of the implications would appear to be incompatible with other stated objectives of public policy.

Canada↗
PubMed1993

Equity and health care: analysis of the relationship between need for care and the utilization of nursing services in Canada.

This paper examined the relationships between need for care and the utilization of nursing services using data from the 1985 Canada Social Survey. The incidence of nursing utilization was estimated using probit regression, and the quantity of utilization, using a self-selectivity model. Further analyses involved exploring use-need relationships by partitioning the sample by need level and by examining interaction effects. It was found that a lower likelihood of using nursing services was associated with lower levels of need, males, married persons, and lower levels of education. Need was also significantly associated with the number of contacts with nurses. While income was not significant, the size of the use-need relationship was affected by socioeconomic and demographic variables, pointing up the necessity of disaggregated analyses.

Adolescent↗
PubMed1992

Biodistribution of Lipiodol following hepatic arterial injection.

Thirteen patients undergoing selective coeliac angiography before insertion of an indwelling hepatic arterial cannula underwent injection of 3 ml radiolabelled Lipiodol (2 MBq 131I) into the hepatic artery at the end of the procedure. At subsequent laparotomy 1-9 days later, biopsies were taken from normal liver and metastases. The radioactivity of this material was measured to establish the tumour:liver ratios. Two patients with large metastases (> 10 cm in diameter) had low ratios. In the remainder, the median ratio at 24 h was 1.5:1 (range 1.1-2.5:1; n = 5) and 2.6:1 (range 1.5-64.0:1; n = 6) at 3-9 days. Four patients underwent single photon emission computed tomography, which confirmed selective retention of Lipiodol in small metastases, although no activity was detected in a large deposit (> 15 cm) 10 days after injection. The tumour:liver ratio in the other three patients increased from 3.0-5.6:1 on day 1 to 4.5-7.2:1 on day 6. This study suggests that Lipiodol may be a useful therapeutic delivery agent to small colorectal liver metastases.

Humans↗
PubMed1992

Cost effectiveness/utility analyses. Do current decision rules lead us to where we want to be?

Despite the growing literature on economic evaluation of health care programmes, little attention has been paid to the theoretical foundations of cost-effectiveness and cost utility analyses and the validity of the decision rules adopted as methods of achieving the stated goals. We show that although applications of the techniques can be used to pursue some managerial objectives in the context of highly constrained environments, such applications are inconsistent with both welfare economic objectives and the interpretations of the findings of these applications. Alternative strategies are identified as potential and practical methods for pursuing welfare economic objectives.

Canada↗
PubMed1992

Biodistribution of lipiodol following hepatic arterial injection.

Lipiodol, a derivative of poppy seed oil, has been used angiographically to improve visualisation of small liver tumours. We have utilised this finding to determine whether intrahepatic arterial injection of lipiodol can be used as a vehicle to deliver selectively 131I into liver tumours. Two groups of rats were studied. Group 1 (control, no liver tumour) received 0.1 ml 131I-lipiodol (1 microCi) into the hepatic artery. Animals were killed at regular time intervals over 30 days and organs were submitted to well-counting. Over 90% of activity remained in the liver at 6 h. Eighty per cent activity was lost from the normal liver, to be excreted in the urine over 30 days. Group 2 animals received intraportal injections of 7.5 x 10(5) MC28 sarcoma cells. Multiple liver metastases were present after 14 days. Animals were similarly studied at each time interval and samples from tumour and normal liver were submitted to well-counting. Lipiodol was selectively retained within tumour and cleared from normal liver. 131I-lipiodol may prove valuable as a delivery agent for radio/chemotherapy to liver metastases.

Animals↗
PubMed1991

Equity considerations in utility-based measures of health outcomes in economic appraisals: an adjustment algorithm.

In this paper we consider whether methods currently used to measure utility of health outcomes are consistent with the equity criteria adopted by researchers. We show that unless the chosen equity criterion is incorporated in the design of the measurement instrument, the derived health state utilities are inconsistent with the equity criterion (except under special circumstances). Adjustment algorithms are derived, based on the axioms of von Neumann-Morgenstern utility theory, which take account of difference equity criteria currently adopted in the literature. The proposed approach is based on simple lottery questions of the type already used widely in empirical studies.

Algorithms↗
PubMed1991

Charging for health care: evidence on the utilisation of NHS prescribed drugs.

The effects of regular and frequent increases in charges for health care on patient utilisation are analysed using monthly data on National Health Service (NHS) prescribed drugs in England for the period 1979-1985. Using a partial adjustment model a utilisation equation of prescribed drugs is estimated for the adult non-elderly population that is subject to the NHS prescription charge. The maximum likelihood estimates of the coefficients of the equation imply that the charges policy followed in the U.K. has led to a significant reduction in utilisation among non-exempt patients. The short-run price elasticity of utilisation is -0.109 and the long-run elasticity is -0.09, while exempt utilisation is unaffected. Although the policy has generated a reduction in the central Government expenditure for prescribed drugs, on the basis of these estimates around 66% of these savings arise from the reduction in service use as opposed to the increased revenue per item of drugs.

Drug Prescriptions↗
PubMed1991

A needs-based methodology for allocating health care resources in Ontario, Canada: development and an application.

In an attempt to limit its health care expenditures, Ontario is, as one option, exploring the possibilities of a capitated system for service delivery payments as opposed to the present mixture of global budgets and fee-for-service. After reviewing the literatures on capitation (primarily American) and on resource allocation (primarily British), the paper sets out to establish a capitation rate, based on 'need' and not prior use, for a range of health services in the northern Ontarian community of Fort Frances-Rainy River. The difficulties and limitations of the needs-based approach are explored. The results reported show the setting of the local population characteristics against provincial average health care utilization data to generate expected use rates, which are then adjusted for need and other factors, particularly relative costs and sparsity. Finally these adjusted rates are applied to current provincial expenditures to derive a target share. This target is then expressed in relation to the planning population to derive the capitation rate.

Budgets↗
PubMed1990

Promoting healthy behaviour: the importance of economic analysis in policy formulation for AIDS prevention.

Considerable attention has been paid in the literature to modification of high-risk behaviours as a means to control the spread of the Human Immunodeficiency Virus. The success of such policies will depend crucially on the underlying causal mechanisms of these high-risk behaviours. To date the application of economics to the problem of AIDS has tended to focus on estimating the economic burden of the condition and the resource consequences of clinical strategies for care. Yet as a behavioural science economics should provide a useful input into the policy process aimed at behaviour modification. In this paper we extend the application of economic analysis to the determinants of individual behaviour to identify (i) the implications of current policies for the incidence of high-risk behaviour and (ii) the wider determinants of behaviour warranting greater attention in the policy-making process.

Acquired Immunodeficiency Syndrome↗
PubMed1990

The relative cost effectiveness of water fluoridation across communities: analysis of variations according to underlying caries levels.

The effectiveness of water fluoridation as a means of reducing the prevalence of dental caries is well established in the dental literature. The case for water fluoridation however rests on the size of this reduction and the benefits that could be produced by using the same resources in other oral health or dental care programmes. In this paper the cost-effectiveness of water fluoridation is analysed for communities of different sizes and with differing oral health levels. Using the traditional model of economic evaluation, data from recent epidemiological studies, and a number of simplifying assumptions, it is shown that the cost per unit health benefit produced from water fluoridation varies by a factor of four according to the existing level of caries prevalence. Furthermore this is likely to be a conservative estimate of the differential impact given the nature of the assumptions. Marked differences in cost-effectiveness are also found for communities of different sizes suggesting that important economies of scale occur in water fluoridation projects. As a consequence cost effectiveness estimates of water fluoridation projects should be assessed on their own merits to ensure that scarce health care resources are used efficiently, i.e. in a way which maximises the impact these resources have on population health status.

Adolescent↗
PubMed1989

Health care charges: lessons from the U.K.

The introduction of increase in user charges is often suggested as a means of restraining the demands on the health care system. Patient charges have been used in the U.K. National Health Service since 1951 in the provision of prescribed drugs, dental treatment and spectacles. Recently, these charges have been extended to eyesight examinations and dental check-ups, while the levels of charges have increased far in excess of the rate of inflation. In this paper the implications of the extended use of patient charges are considered from the perspective of patients, the health care system and the Government, using available evidence on the effects of charges on consumer behaviour.

Fees and Charges↗