Equity in health care prioritisation: An empirical inquiry into social value

Abstract

The value of QALY gains for different patients may be recalculated using equity weights, but it is unclear which interpretation of equity should be used: severity of illness, fair innings or proportional shortfall. We set up an experiment to analyze which of these equity concepts best reflects people's distributional preferences. Sixty respondents assigned a priority rank to the treatment of 10 conditions using the paired comparison technique. We described these real-life conditions by their actual QALY profiles, i.e. in terms of age, disease free period, duration of disease, quality of life, and life years lost. Next we determined the priority rank order of the 10 conditions by the three equity concepts, using the weights that each equity concept attributes to the different units of the QALY profile describing the 10 conditions. To explore the social interpretation of equity, we compared the observed and theoretical rank orderings using Spearman correlations. All correlations were significant at a 0.05 level. Fair innings best predicted the observed rank order of the 10 conditions (r = 0.95). Weaker correlations were found for proportional shortfall (r = 0.82) and severity of illness (r = −0.65). This result calls attention to health policy, because actual health care decisions often reflect concerns of severity of illness. This raises the question if health care decision makers evaluate the claims of different patients for health care by appropriate criteria.

Introduction

The concept of efficiency in the distribution of health is usually taken to imply that people who can gain QALYs in a relatively cheap way are more entitled to treatment than other people are. Societal preferences, however, have demonstrated that other individual characteristics may also affect priority setting, because the principle of health maximization may lead to uneven distributions of health which conflicts with people's equity concerns. To incorporate social concerns about equality in health in economic evaluations several authors have advocated operationalization of an equity-efficiency trade-off [1], [2], [3]. This trade-off reflects the willingness to decrease the total amount of benefits from our health care system, if this results in a more equitable distribution of health effects. Unfortunately, equity is an ethical concept that has no precise definition. Ever since the concept of the equity-efficiency trade-off has been introduced, it has been debated which equity concern(s) should be included in the trade-off. To contribute to this debate, we set up an empirical study to explore the social interpretation of equity.

There seems to be agreement that the definition of equity should be found in the health domain, but it is unclear what kind of measure of inequalities in health must be defined. Different authors have tried to persuade others to the use of different equity concepts, like severity of illness [4] and fair innings [2]. The severity of illness approach embodies the feeling that people facing severe illness must be rescued, whilst this urge to help declines when the health conditions are less severe [3]. Therefore, patients in the most critical condition receive the highest priority, e.g. patients facing the threat of immediate death or a severe handicap. In effect, this approach gives highest priority to patients with the poorest health prospects without treatment. There is however no consensus that indeed patients with the poorest health prospects are always the most deserving [5]. People who adhere to the fair innings argument believe that the goal of equity adjustment should be to reduce differences in lifetime experience of health instead of reducing differences in future health [2]. Not only people's health prospects are then relevant to evaluate their claim on health care, but also the amount of health that they have already consumed. This approach implies that in many cases the young people should get priority over the old, as the old has already had more time alive than the young (and presumably not in such a bad health state that the young will have consumed more QALYs).

Empirical studies revealed public support for both severity of illness and fair innings [6], [7], [8]. Therefore it is also possible to argue for equity concepts that combine the two principles together [9]. A combination concept may take an intermediate position and help to clarify how priorities are set in the case of a conflict between severity of illness and fair innings. Recognizing this possibility, Johannesson [10] and Stolk et al. [11] have described an equity concept that takes an intermediate position: the concept of proportional shortfall. Proportional shortfall makes a particular trade-off between the goals regarding equality in total and future health. Proportional shortfall has in common with fair innings that the size of the health gap is relevant, but it agrees with severity of illness that also the remaining no-treatment QALY expectation should be taken into account. From this viewpoint equity weights are not simply proportional to the absolute size of the health gap caused by a condition. Rather, equity weights should be determined on the basis of the amount of QALYs that a patient loses proportional to this person's remaining QALY expectancy in normal health (e.g. calculated as the average expected number of QALYs for the population of that age and sex). Higher equity weights then apply if a patient loses a greater fraction of his or her remaining QALY expectation. Proportional shortfall thus values relative changes in expected QALYs, irrespective of the number of expected QALYs concerned [10]. This reflects the idea that everyone is equally entitled to live out his or her remaining life span, no matter whether the remaining life span is long or short.

In the literature on inequalities such proportionate equity concepts have been discussed frequently [12], [13], [14], [15], but little is known about the social support for this type of combination principles. Usually the two equity concerns that are combined are evaluated separately. In a recent paper Cuadras-Morató et al. [12] compared support for the absolute and proportionate equity concepts using axiomatic bargaining theory. Cuadras-Morató et al. recruited respondents to solve resource allocations, whereby the possible solutions specified shares of the available budget that would be allocated to different patients. The solutions represented six different distributive and equity concepts among which the utilitarian position, the fair innings argument and a proportionate equity concept similar to the proportional shortfall approach. Respondents had to indicate which solution they found most attractive. In that way this study explored what equity concept prevailed in circumstances where different views would result in different priorities [12]. This experiment found no dominant principle, but strongest support was for the proportional solution and fair innings. Which of these two solutions was preferred in the different situations depended on the differences in the capacity to benefit, the health gap, and the context. The authors conclude that more research into social support for equity concepts is warranted, and they advise to explore benefits of realistic examples in future surveys to study on a less abstract level support for different equity concepts.

Building on the studies discussed above we further explored social preferences for equity. In our study we used realistic cases to test support for different equity concepts, as suggested by Cuadras-Morató et al. [12]. We asked our respondents to priority rank treatments of 10 conditions using the paired comparison technique. To explore the social interpretation of equity, we compared this observed rank order to the rank orderings expected by the three equity concepts. This study contributes to existing literature by concentrating on the way in which people balance different equity concepts in a series of forced choice questions. The purpose is to see whether combined information on the different choices reveals the underlying decision process and weighting of equity concerns.