The role of adaptation to disability and disease in health state valuation: a preliminary normative analysis

Title: The role of adaptation to disability and disease in health state valuation: a preliminary normative analysis
Authors: Menzel, Paul and Dolan, Paul and Richardson, Jeff and Olsen, Jan Abel
Publisher: Social science & medicine, 55 (12). pp. 2149-2158
ISSN: 0277-9536
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Abstract: Chronically ill and disabled patients generally rate the value of their lives in a given health state more highly than do hypothetical patients imagining themselves to be in such states. Much of this difference may be due to actual patients’ adaptation to their health states, a phenomenon that would not typically affect the ratings of persons who only hypothetically imagine themselves to be patients. This article pursues a non-empirical, normative question: does such adaptation render actual patients’ ratings of quality of life morally questionable for purposes of resource allocation? Distinguishing the different basic elements in patient adaptation reveals why, and in what respects, people are pulled strongly in opposite directions in responding to this question. Several more explicit moral arguments against using adapted patients’ ratings have been articulated by economists and philosophers, and others are developed by the authors. While most of these arguments do not survive careful analysis, several do. Given the subsequent complexity of the matter, it is argued that: (1) Neither solely actual nor solely hypothetical patient perspectives should be used for rating quality of life. (2) Even if representatives of the general public acting as hypothetical patients provide ultimately the best perspective from which to discern societal values about health states, patients’ values that are often influenced by adaptation must still be conveyed to and clearly understood by public representatives as a critically important fact about health-related quality of life. The article also points to the need for much additional work on adaptation, both empirical research and normative analysis.

An inquiry into the different perspectives that can be used when eliciting preferences in health

Title: An inquiry into the different perspectives that can be used when eliciting preferences in health
Authors: Dolan, Paul and Olsen, Jan Abel and Menzel, Paul and Richardson, Jeff
Publisher: Health economics, 12 (7). pp. 545-551
ISSN:  1057-9230
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Abstract: There are a number of perspectives that an individual could be asked to adopt in studies designed to elicit preferences for use in informing resource allocation decisions in health care. This paper develops a conceptual framework that clearly distinguishes between six different perspectives. It is argued that the appropriate perspective to use depends on normative considerations and the particular policy context to which it will be applied. We suggest a future research agenda that explicitly addresses these considerations and which involves direct empirical investigation into the effect of perspective on preferences.

Is it really possible to build a bridge between cost-benefit analysis and cost-effectiveness analysis?

Title: Is it really possible to build a bridge between cost-benefit analysis and cost-effectiveness analysis?
Authors: Dolan, Paul and Edlin, Richard
Publisher: Journal of health economics, 21 (5). pp. 827-843
ISSN: 0167-6296
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Abstract: Cost-benefit analysis (CBA) is a recognised as the economic evaluation technique that accords most with the underlying principles of standard welfare economic theory. However, due to problems associated with the technique, economists evaluating resources allocation decisions in health care have most often used cost-effective analysis (CEA), in which health benefits are expressed in non-monetary units. As a result, attempts have been made to build a welfare economic bridge between cost-benefit analysis (CBA) and cost-effectiveness analysis (CEA). In this paper, we develops these attempts and finds that, while assumptions can be made to facilitate a constant willingness-to-pay per unit of health outcome, these restrictions are highly unrealistic. We develop an impossibility theorem that shows it is not possible to link CBA and CEA if: (i) the axioms of expected utility theory hold; (ii) the quality-adjusted life-year (QALY) model is valid in a welfare economic sense; and (iii) illness affects the ability to enjoy consumption. We conclude that, within a welfare economic framework, it would be unwise to rely on a link between CBA and CEA in economic evaluations.

Modelling valuations for EQ-5D health states: an alternative model using differences in valuations

Title: Modelling valuations for EQ-5D health states: an alternative model using differences in valuations
Authors: Dolan, Paul and Roberts, Jennifer
Publisher: Medical care, 40 (5). pp. 442-446
ISSN: 0025-7079
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Abstract: Objectives. The EQ-5D is a preference-based measure of health and is increasingly being used in the evaluation of health technologies. A ‘tariff’ of values for all 243 EQ-5D health states has been generated using direct valuations on a subset of these states. The tariff is used to express the value of differences between health states, and so this paper explores whether a tariff with better predictive ability can be calculated using differences between values rather than using the values themselves. Methods. The original tariff (reported in this journal) was based on valuations for 42 EQ-5D states elicited from a representative sample of 2997 members of the UK general population using the time trade-off method. This same data are used to estimate a tariff based upon the differences in value between the worst possible state (33333) and all other states. Results. A simple model that fits the data well is one in which the differences in value between 33333 and all other states are explained in terms of the change in each dimension plus a term to pick up whether some dimensions change by the maximum amount whereas others do not change at all. The mean absolute difference between the actual values and those predicted by this model is 0.03 (compared with 0.039 in the original model). Conclusion. The model presented in this paper predicts the difference between 33333 and all other states remarkably well and can be used to generate a tariff for all EQ-5D health states. In fact, this model more accurately predicts the values of states for which there are direct observations, and so we recommend its comparison with the original model in evaluative studies.

To what extent can we explain time trade-off values from other information about respondents?

Title: To what extent can we explain time trade-off values from other information about respondents?
Authors: Dolan, Paul and Roberts, Jennifer
Publisher: Social science & medicine, 54 (6). pp. 919-929
ISSN: 0277-9536
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Abstract: The time trade-off (TTO) is one of the most widely used health state valuation methods and was recently used to develop a set of values for the EQ-5D descriptive system from 3000 members of the UK general population. However, there is currently very little understanding of precisely what determines responses to TTO questions. The data that were used to generate this set of values are ideal for addressing this question since they contain a plethora of information relating to the respondents and their cognition during the TTO exercise. A particularly useful characteristic of this dataset is the existence of visual analogue scale (VAS) valuations on the same states for the same respondents. The results suggest that age, sex and marital status are the most important respondent characteristics determining health state valuations. The VAS valuations were found to add very little to the explanatory power of the models.