Factores asociados a la búsqueda y uso de servicios de salud: del modelo psicosocial al socioeconómico.

This article includes the results of a multi-level conceptual approach review, considering four models of analysis, delving into the determinants and the explanatory factors in the process of search and use of health services. Such models are: psychosocial, epidemiological, sociological, and socio-economic. The implications, determinants, and characteristics of utilization of health care services have been subject to scrutiny since the eighties. Research on this matter has not been independent of the process of reform, which has been carried out simultaneously in virtually every country in the world. In fact, establishing adequate health services for patients who need them most has become a generally accepted priority. For the purpose of this study, and as a preamble to understanding the process of search and use of health services, the concept of need, along with its applications in the different models of service use, must be defined. In the literature, there are four types of need: a) normative need, that which is expert-defined as such in a given situation, b) felt need, which corresponds to a perceived lack of something beneficial to the individual, c) expressed need, one not only experienced, but also articulated by the individual, and d) comparative need, i.e. a standard that meets the same characteristics of another receiving certain coverage or service. This paper will refer to the expressed need, which may or may not correspond exactly to the use of health care services. Along the same lines, the concept of demand, applied from an economic perspective, will be utilized as a synonym for use. The implementation of reform processes and the evaluation of the possible implications of such reforms require extensive knowledge regarding the determinants of use of health care services. A main determinant can be identified, for example, when an individual uses such services, sometimes repeatedly, because he is in a situation of need (experienced), understood as the perception of discomfort or illness. There are certain biological differences (i.e. sex and age) that might explain some of the variations observed in the relationship between situations of need and use. However, could there be other reasons that would lead to use? If so, this situation might create unnecessary extra work for professional health care providers preventing them from engaging the real needs of the population served; on the other hand, if there are any other motives (besides the absence of necessity) causing an individual, or group of individuals, not to meet his care needs, he may be at risk. It is widely known that not all health problems are reported to physicians by patients at the time of consultation. Also, there are great numbers of single users who are responsible for the utilization of a large portion of consultations intended for that population, taking advantage and, occasionally, using health services without having, from a medical standpoint, a clear justification to do so. These examples are extremes that can be observed as patterns of use that are determined by the perceived need for health and a long list of factors described from different disciplinary perspectives. Analyzing the search and use of health services implies studying availability and accessibility to them. Although the measurement of these variables is not exact, it is used in most studies. When considering use by socio-economic group accessibility, the fairness of the system in question is also evaluated. This is highly relevant because problems of use of services are related to health equity and accessibility, two challenges currently being addressed by a substantive reform of the health systems in most countries of the world; particularly in Latin America, and more so in Mexico. Thus, this paper intends to address, through a review of different theoretical models, factors affecting the search and use of health services. It assumes that the central premise in the context of health sector reforms in Latin America, especially in Mexico, is that the health service users have come to occupy a leading role in establishing the health needs addressed by care systems. Indeed, the main issues of structural adjustment in health systems are related to setting health needs according to epidemiological changes, changes in perception of diseases, and changes in the variables of equity, efficiency, coverage, and accessibility to health systems for different population groups. From this new perspective, the health systems, in turn, propose relevant changes in the interaction between the two main social actors within this reform process: first, the behavior of suppliers (any institution that provides health services to the population), and second, the behavior and perceptions of consumers (population using health services demanded from a particular institution). The path converges when both social actors represent the process of seeking and obtaining medical care, as determined by a number of variables and constraints addressed in this article through different conceptual approaches, i.e. whenever the explanatory conceptual model is used, the process of medical care is primarily conceived as two chains of activities and events where participants are parallel -the care- giver on the one hand, and the client or user of health services on the other. In an extended approach, use and its determinants have much to do with the study of accessibility, coverage, and equity in health. Some authors claim that, under this approach, the study of accessibility and coverage in health are made identical to the determinants of service utilization. This wider vision includes various aspects, considering use as a schematic sequence of events from the time the need for medical attention arises until it initiates/is followed by the use of medical services. Throughout this process, psychosocial and epidemiological determinants of care are identified, including seeking process aspects such as health-related beliefs, confidence in the health care system, disease frequency, pain tolerance, and presence of disability. This schematic succession of events is precisely what has allowed the study of health service use to exhibit different approaches, which in turn has led to the creation of various psychosocial and epidemiological models that have attempted to explain why the population does not use health services. From an economic perspective, the literature on health service utilization mainly considers two approaches: the traditional approach and the managerial approach. These provide different but complementary explanations regarding demand and investment in health services. The traditional approach to demand for health services is based on consumer theory, where demand for medical services is mainly determined by the patient but conditioned by the health system. Within this emerging model, demand for health services is the result of a problem of inter-temporal utility maximization of the patient, and considered a function in the production of health. The managerial approach, related to human capital theory, considers information asymmetries between doctor and patient regarding the type and quantity of necessary medical treatment. In this context, the decision making process can be divided into two parts: first, patients initially choose whether or not to seek treatment, and then, once the patient begins treatment, the physician determines the number of visits and use of services for tracking, monitoring, and controlling the damage that initially triggered the stages. To specify a model of demand for medical services as a two part process, we should distinguish, at each stage, «who makes the decisions?», and «what is the set of explanatory variables?» Describing the initial demand for medical services should be considered an approach that reflects the patient's decision to visit the doctor. The economic models elucidate this decision as the explanatory variables arise from the need to demand or investment, i.e. the doctor chooses the treatment considering not only medical criteria, but also economic incentives. Both processes can be assumed to have the same set of explanatory variables, but the explanation may differ depending on the stage of the decision-making process being analyzed, the type of coverage, the service availability, and the provider's behavior. In this article, each one of the above phases is examined from different perspectives, describing the conditions and determinants of the process of search and use of health services and making a cross-analysis for each model reviewed in a contingency matrix. Finally, a comprehensive analysis of the models is proposed as a starting point for finding a model that allows, in a trans-disciplinary way, to elucidate a better explanation of the determinants and constraints of the process of search and use of health services. [ABSTRACT FROM AUTHOR]