Contenu du sommaire : Nouvelles approches micro-économiques de la santé

Nouvelles approches micro-économiques de la santé

• Présentation générale - Lise Rochaix, Cyrille Piatecki, Claude Le Pen p. 1-6
• Sur la spécificité économique des soins de santé - Jacques H. Drèze p. 1-9

• Les outils d'analyse et de mesure en économie de la santé

  • Asymétries d'information et incertitude en santé : les apports de la théorie des contrats - Lise Rochaix p. 11-24
    Information Asymmetry and Health Uncertainty: The Contribution of Contract Theory by Lise Rochaix The imperfect and even asymmetric nature of the information at the patient's disposal calls into question the use of the standard neo-classical model and has led to application of microeconomic principal-agent models. This paper sets out to assess recent applications of contract theory to the health sector. Although the latter offers a relevant model of interpretation, it is still of relatively little use, mainly because of the fragmentation of decisions relating to the health-care market. The scope and limitations of such an approach must therefore be examined. This is all the more important in that new families of theoretical models involving multiple principals, multiple agents or third parties are now offering fresh angles of application to the field of health.
  • L'hypothèse de demande induite : un bilan économique - Stéphane Jacobzone, Lise Rochaix p. 25-36
    The Induced Demand Hypothesis: an Economic Assessment by Lise Rochaix and Stéphane Jacobzone In health economics the induced demand hypothesis is bringing about a transformation in the way health-care demand is perceived. It posits that health-care demand does not simply reflect choice in terms of patient utility but can also be determined by a doctor's implicit motivation. This extremely polemical hypothesis has formed the basis for numerous empirical studies. In this paper we demonstrate that the controversy arises partly from the exact formulation of the hypothesis. A detailed analysis of available work on the extent of induced demand leads to a qualified judgement. On the empirical level, the academic debate seems to be partly closed, although it has not been definitively resolved given the limitations of the tools. Nevertheless, this economic assessment underlines the weight of the incentives to which doctors are exposed in the practice of their profession. This is not without an effect on discussion of payment systems for providers and may shed light on certain economic policy choices.
  • Théorie de l'utilité et mesure des états de santé, le débat QALYs-HYEs - Claude Le Pen p. 37-54
    Utility Theory and Health Status measurement: the Debate QALYs vs HYEs by Claude Le Pen A vigorous debate has recently opposed int the field on the economic assessment of medical technologies two methods to value health states : the "Quality Adjusted Life Years" (QALYs) and the "Healthy Years Equivalents" (HYEs). For a given health state, the QALYs are defined as the sum of life years allowed in a définie health state, each year being weighted by a coefficient, which reflects the utility of is "quality". The coefficient value varies between 0 and 1, 0 being attached to the worse quality and 1 to the best. This indicator, whose simplicity and intuitive appeal certainly explain the great success, faces nevertheless serious theoretical probems. It can be shown in fact that the preference pattern of an agent who would prefer health state A to health state B if and only if the number of QALYs in A is grater than that in B, obeys a set of restrictive assumptions, so that the psychological profile of the agent lacks credibility. Some authors have thus proposed an alternate measurement, the HYEs, which have the advantage to give an integrated utility measure of both quality and quantity of life, without requiring a complete and restrictive specification of the utility function. More general from a theoretical point of view, this concept proves impossible to be practically implemented. The methods designef to compute empirically the HYEs implicitly require in fact the same limitung assumptions than the QALYs. So, we have from one hand a concept which is easy to implement empirically but without a great theoretical relevance and, from the other hand, a concept which is richer at the theoretical level but is disappointing at the pratical level. Apart from the technical matters, the debate has the interest to reveal the meaning and the limit of the application of utility theory to the measurement of health state.
  • L'indicateur QALYs à la lumière de la théorie de l'utilité espérée multi-attribut explicitement décomposée - Anne-Marie Fericelli, Catherine Le Galès, Catherine Buron p. 55-71
    An Explanatory Analysis of the QALYs Indicator in the Light of Multi- Attribute Utility Theory by Catherine Buron, Catherine Le Gales and Anne-Marie Fericelli For the past few years a number of health microeconomists have been suggesting that quality adjusted life years (QALYs) should be included in economic analysis. The first half of the paper offers a critical review of existing QALYs models in the light of Keeney and Raiffa's multi-attribute utility theory (MUT). In the second half, the conditions for QALYs modelling with this theory are explained and the various hypotheses (independence in terms of utility, mutual utility and additive utility) are stated and then discussed. Whilst highlighting the lack of evidence for the empirical validity of the hypotheses required for QALYs modelling consistent with the MUT, the survey demonstrates the importance of the MUT for modelling utility functions relating to chronic states of health.
  • Une approche hedonique de la formation des prix des médicaments remboursables - Julien Werle, Vincent Perrin, Edouard Martin, Stéphane Jacobzonne p. 73-99
    Reimboursed drugs price setting: a hedonic approach by Stéphane Jacobzone, Edouard Martin, Vincent Perrin and Julien Werle A hedonic pricing model is used to describe price setting in the case of reimbursed drugs in France. The data used cover 24 % of the French market over the period 1980-1993, allow for a detailed description of physical and chemical properties of the products, and have been matched with business survey data. They pertain to two main therapeutic classes (anti-ulcer drugs, antihypertensive drugs). lucts, from the effects of changing market structure. These indices, which are adjusted for quality, grow more rapidly than official indices, the bias averaging 20 %. Price dynamics also depend on whether the product is innovative or not. This effect has not been found in other studies. It suggests that given their environment firms have an incentive to introduce, new - and therefore more expensive- drugs.
  • Comparaison des différentes mesures d'efficacité technique : une application aux centres hospitaliers français - Benoît Dervaux, Hervé Leleu p. 101-119
    Comparison of Different Measurements of Technical Efficiency: a Study of French Hospitals by Hervé Leleu and Benoît Dervaux The enthusiasm for non-parametric techniques of assessing production frontiers in hospitals stems from their ability to take account of the sector's specific features. "Virtually all such techniques use data envelopment analysis (DEA) methodology with various hypotheses for returns to scale. In this paper, after examining the theoretical features of various efficiency measurements, we set out to assess the productive efficiency of 137 French public hospitals. We analyse the impact which the choice of efficiency measurement has on score distribution and the outcome of explanatory models of hospital performance. We find that the choice of measurement alters the efficiency score distribution but has little effect on hospital classification in terms of relative performance.
  • Mesure de l'équité des modes de financement et de distribution des soins de santé : aspects méthodologiques avec illustration sur l'Irlande - Brian Nolan p. 121-130
    Measuring the Equity of Health-Care Distribution and Funding Methods: Methodological Aspects with Ireland as Illustration by Brian Nolan This paper sets out the methodological difficulties encountered in measuring the equity of health-care distribution and funding. Some of these difficulties are shared by other fields of the economy, but the most complex remain specific to this area, such as the problem of finding a suitable measurement for medical needs It is also difficult to establish a direct relationship between macroeconomic performance and microeconomic behaviour in terms of production and consumption. Yet more complicated is the fact that needs assessment should be based on patients' capacity to benefit from care rather than on the degree of illness, and on the distribution of health improvements among the community rather than on the utilisation of health care. Indeed, much of the health-care currently available would be unable to reduce health inequalities even if targeted at the most disadvantaged social and economic categories.

• Les stratégies d'acteurs

  • Une analyse micro-économétrique de la consommation de tabac basée sur l'enquête UK Health and Lifestyle - Andrew M. Jones p. 131-146
    A microeconometric analysis of smoking in the UK Health and Lifestyle Survey by Andrew M. Jones This paper provides an overview of microeconometric evidence on various aspects of smoking using data from the UK Health and Lifestyle Survey (HALS1). In doing so it illustrates how the choice of an appropriate statistical model is influenced by the survey design and the definition and measurement of variables. Results are reported for parametric survival analysis of the age of starting and the number of years of smoking; univariate and bivariable probit models for attempts and success in quitting smoking; and both generalised Tobit and count data models for the number of cigarettes smoked.
  • Recours aux soins des adultes et mode de gestion du risque - Georges Menahem p. 147-171
    Adult Health-Care Demand And Risk Management Methods by Georges Menahem The paper shows how allowance for individual attitudes to risk can improve the "health-care demand" model. The assumption that individuals differ according to the level of overall risk that they are prepared to accept produces a coherent analysis of state of health, demand for medical care, and prevention "investment". Logistic regressions for a representative cross-section of the French population consisting of 13 150 adults show that this level of "programmed risk" correlates positively with declared morbidity and objective morbidity in terms of medical consumption. Conversely, it correlates negatively with prophylactic medical visits.
  • Âge, temps et normes : une analyse de la prescription pharmaceutique - Valérie Paris, Pierre-Jean Lancry p. 173-187
    Age, Time and Standards: An Analysis of the Pharmaceutical Prescription by Pierre- Jean Lancry and Valérie Paris The introduction of coherent policies to control health spending requires definition of regulating variables likely to alter the behaviour of the various players (patients, producers of medical goods and services, health insurance bodies and supervisory authorities). Medicines play a very substantial part in outpatient medical consumption. As the largest item of expenditure, mainly associated with the work of general practitioners, they have long been the subject of special measures. In this work we focus on the determining factors of the pharmaceutical prescription. Using data on supply and professional practice (age, gender, occupation, place of training, practice locality, etc.), demand (age, gender, mortality rate, etc.) and market conditions (doctor density, average workload in the district, officially recognised sector, etc.).

• Les enjeux de la régulation

  • Systèmes mixtes d'assurance maladie, équité, gestion du risque et maîtrise des coûts - Stéphane Jacobzone p. 189-205
    Mixed Health-Insurance Systems, Equity, Risk Management and Cost Control by Stéphane Jacobzone This paper studies the mixed nature of health-insurance systems, listing the various arguments in favour of state intervention. The latter include the redistribution principle and potential dysfunctions in insurance systems. The importance of collective-choice models for understanding the nature of balances is demonstrated. This makes it possible to address problems relating to incentive management in health-insurance systems. Of the factors which affect expenditure patterns, the interaction between insurers/payers and care providers would seem to be determining, especially as regards the pace and type of technological innovation encouraged by reimbursement. A discussion of organisational forms shows the advantage of integrated methods of social security coverage, possibly coupled with development of lump-sum payments for the providers.
  • La réglementation hospitalière : tarification par pathologie ou achat de soins ? - Florence Naegelen, Michel Mougeot p. 207-220
    Hospital Control: Pathology-Based Charging or Purchase of Care? by Michel Mougeot and Florence Naegelen Many countries have introduced incentive systems in order to control health spending. Pathology-based charging rests on the logic of competition through comparison, whereas the quasi-markets in which a care purchaser invites tenders from providers are based on a bidding logic. This paper compares the performance of these two methods of organisation in a context of adverse selection and moral hazard where quantity is fixed and quality respected. The conditions for implementing the two systems are analysed when they are identical. It is demonstrated that purchase of care through an invitation to tender with incentive clauses leads to an improvement in social welfare and a drop in the cost of care.
  • L'équité dans le modèle de "concurrence organisée" pour la régulation d'un système de santé - Claude Schneider-Bunner, Maryse Gadreau p. 221-237
    Equity in the "Planned Competition" Model of Regulating a Health System by Maryse Gadreau and Claude Schneider-Bunner The distributive logic of European health systems (contribution depending on income and use depending on need) is indicative of the importance attached to the principle of equal access to health-care. However, reforms introducing competition are arousing interest in Europe and have been piloted in the United Kingdom and the Netherlands. To what extent is equity still maintained? This paper uses a threefold typology of justice theories (egalitarian, liberal and Rawlsian) to analyse the "planned competition" model and its European pilots. The underlying conception of equity is ambiguous: all three dimensions are present, indicating the hesitations of equity policy and reflecting the pluralism of the principles in whose name the health system players are acting.
  • Décisions de recours au système de soins dans la prise en charge des personnes âgées dépen­ dantes : un modèle de choix discret dynamique - Agnès Gramain p. 239-254
    Long-Term Care Choices of Disabled Elderly and their Family Caregivers : a Dynamic Discrete Choice Model by Agnès Gramain This article presents an application of a dynamic discrete choice model to the analysis of care arrangement of disabled elderly. This method allows us to examine the main determinants of the demand for in-home services and nursing-home admission. Data were collected in 1993 and 1996 in southern France, and describe the evolution of care arangement for 155 elderly and their main caregivers. Our results show that the call for professionnal help is obviously a response to time and budget arbitrage. They also indicate that ageing and disability increasing do not systematically induce a higher probability of formal help use. The care arrangements of disabled elderly seem to be very stable whatever the type of formal services and the level of incapacities. Our estimations give some elements for the evaluation of the in-home services' efficiency in terms of reduced probability of nursing-home admission. It suggests that the nursing-home admission probability depends of a rather complex profile of characteristics including the type of disability the elderly persons suffer from, their socio-economic status and the formal and informal caregivers that help them.

• Notes

  • Expliquer la croissance des dépenses de santé : le rôle du niveau de vie et du progrès technique - Frédéric Rupprecht, Alain Quinet, Yannick L'Horty p. 257-268
    Explaining Health Expenditure Growth: the Effect of Standard of Living and Technical Progress by Yannick L'Horty, Alain Quinet and Frédéric Rupprecht The aim of this paper is to explain health expenditures growth in France since 1970. In a first section, we survey empirical studies and deal with two major issues : is income elasticity of health greater than one ? What is the impact of supply factors, like medical technical progress ? In a second section, we estimate an health expenditure function using French data between 1970 and 1995. Health expenditures grow with the standard of living measured with GNPper capita, and that effect could explain more than two fifth of health expenditures growth since 1970. Price elasticity is high, even if we take into account financing with French Social Security system. Medical technical progress has also a strong impact. The aging of population has a minor effect.