PREVENT,VE

MEDIC,NE

6, 134~ 142 (1977)

Overview:

Baylor

Health and the Planning Systems’

of Health Care

DAVID CARD&

AND ROBERT

M. THRALL

College of Medicine,

Rice University,

Houston,

Texas 77030

Implicit functions of a health care system which are often omitted or improperly emphasized are the study and promotion of individual health. This situation stems from the fact that health care systems are primarily based on the concept of disease, while the attributes of health (positive health) have not been investigated and objectively defined. However, an operational definition of the elusive concept of health appears possible today and is discussed in this paper. If the hypotheses that health can be improved and deterioration due to age can be retarded are accepted, then the consequences of these possibilities must be analyzed in relation to the planning of health care systems and to the planning of national health care programs. Thus, any attempt to describe the natural history of the health process must include the effects of interventions aimed at the promotion of health in the absence of disease. These effects must be defined so that quantitative criteria, which would serve as the basis for predictive medicine, can be established. Quantitative predictive medicine is necessary in order to evaluate the effectiveness of preventive measures. While it is widely recognized that the prevention of disease is one of the major goals of a health care delivery system, the methods presently used to evaluate altrnative courses of action are notoriously limited.

The economic social burden caused by disease is having a major influence on present views on the planning of health care &livery systems. It has stimulated interest in the analysis and discussion of indicators of “health” as an objective means of evaluating the health status of human communities at certain points in time. It has also stimulated the analysis of conceptual issues such as, “What is health?“. The concept of health is, indeed, an elusive one, and perhaps for this reason has been frequently banished from practical consideration. To continue to do so, however, might entail undesirable consequences. ON THE CONCEPT

OF HEALTH

In regard to the concept of health, Socrates, in Plato’s dialogue “Georgias,” states: “Healthy, as I conceive, is the name which is given to the regular order of the body, whence comes health and every other bodily excellence: is that true or not?“; and Callicles responds: “True.” This definition is not much different from the definitions one may encounter in respected general dictionaries of today. Compare with the following. “Health is the condition of an organism or one of its parts in which it performs its vital functions normally or properly” (4 1). ’ This paper is an abbreviated version of “The Concept of Positive Health and the Planning of Health Care Systems” presented at the Conference on Dynamic Modelling of Medical Care Systems sponsored by IIASA’s Biomedical Project, WHO, The Cancer Centre AMS USSR, and the USSR Ministry of Public Health, Moscow, December S-10, 1975. 2 Address for reprints: David Cardus, M.D., P.O. Box 20095, Houston, Texas 77030. 134 Copyright @ 1977 by Academic Press, Inc. All rights of reproduction in any form resewed.

ISSN 0091-7435

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The common feature of these two definitions is that health is comprehended as some sort of order or normal behavior of bodily function. How it comes about, or whether this order, or normal behavior, has a purpose or not, is not considered. A much deeper thought is expressed by Kant in his “Metaphysical Elements of Ethics.” In discussing the strength of the mind in relation to virtue and vice, he says: “this question would nearly be the same as the question of whether a man in a fit of illness can show more strength than in a healthy man condition; and this may be directly derived, since the want of health, which consists in the proper balance of all the bodily forces of man, is a weakness in the system of these forces, by which system alone we can estimate absolute health.” This concept of health is much closer to the following definition found in a modern scientific dictionary: “Health is a state of dynamic equilibrium between an organism and its environment in which all functions of the mind and the body are normal” (10). It is clear that, through the centuries, the concept of health has become progressively impregnated with two fundamental ideas: that the body must be conceived as some sort of system and that this system is adapted to a certain environment. The notion that the body must be conceived as a system, as Kant conceived it, is as important as the fact that an organism always operates in some environment. The adjustment, or adaptation, of the organismic system to the environment is fundamental to any conceptualization of positive health. It is through this adjustment that it is possible to counteract the causes of disease or perturbation of the organismic system. This means that health is not only the result of the elimination of the causes of disease but also the development of active and specific mechanisms by the organismic system that allow accommodation to the causes of disease when they become part of the organism’s environment. Health is, then, an experience. It is the capacity to build biological history in the sense that, for changes in the environment which are a repetition of past experiences, the organismic system has readily available adaptive mechanisms; whereas, for changes in the environment which are new experiences, the system has the capacity to develop new adaptive mechanisms. Several questions have been raised in attempting to define health. One of them is, “Is it possible to define health?” Another is, “Is it necessary to define it in order to measure it?” We will lay aside the question of whether or not it is possible to define health. The multiple attempts in recent literature to define health (11,12,15,33,44,45) indicate that in this area, as in others, there are optimists and pessimists. An important reason for avoiding a precise definition is that the development of measurements of health may not require a definition for which there is total agreement. The difficulties in measuring health may be similar to the difficulties physicists have had in defining time. In fact, time, as an independent entity, has not been defined. Yet this has not prevented the development of multiple procedures for measuring time. In turn, measurability does not imply that one has a hold on an absolute concept. Time, in spite of accurate measurement, is only a relative concept, as are space and acceleration. The concept of health is probably also a relative one, one for which the related dimensions must be discovered.

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FIG. 1. Interacting elements to be considered in developing a concept of health. cated by broken lines deserve immediate attention.

Relationships indi-

In fact, health probably can be defined only if it is recognized (see Fig. 1) that there are at least three systems that interact: the psychobiological system that is man, the physical and biological system that constitutes man’s natural environment, and the social system that he has created. It is a truism to say that each of these systems is highly complex, but perhaps it is not so generally perceived that man must be considered as a complex system himself and not simply as a component of the natural and social systems. Recognizing the simultaneous existence of these three systems, it is possible to define health from three relativistic points of view: from a medical viewpoint that considers man as an organismic system; from an ecological point of view that considers man as an element of nature; and from the point of view of the administrator who considers man as a source of needs that must be satisfied by the available resources within his control. THE MEASUREMENT

OF HEALTH

Several investigators in the United States and other countries have tried to construct indices of “health” for the purpose of assessing health status and detecting changes in this status over time. The problem is that these indices are more of disease than of health (23). The use of disease indicators or of criteria of health services utilization as measurements of health is only tenable because, as yet, parameters or indicators of positive health have not been proposed or explicitly defined. Accepting the fact that indicators of positive health are not presently available for statistical analysis, several “health” indices, based on disease and its impact

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upon the individual and society, have been proposed since the late 1930’s (36). These indices vary in the object of study, the variables selected, the methods of data collection, and the computational models used. The object of study is either the individual (13,19,21,28,29), a population (2,20,26,38), or a health care system (18,24,39). The variables may be biologic, environmental, or health service or other activity counts. The methods of information gathering have varied from multipurpose or specific-purpose surveys (19) to the use of medical and behavioral observations (21) to the use of patient tracers (18) or actuarial data (2). The models may consist of simple, intuitive, algebraic expressions (26) or more sophisticated, stochastic, probabilistic formulations (7). Among all of these efforts, there is but one group (3) that has attempted a quantitative approach to the WHO definition of health as the “physical, mental and social well-being (of the individual), not merely the absence of disease or infirmity.” Although laudable, the prospects of this effort are also limited because, although the three dimensions of health are considered, the variables used are still essentially disease indicators. Some of the most elaborate models (13) emphasize level of function and prognosis as the two major parameters in the construction of health indices models. The concept of prognosis, as applied to populations rather than to individuals, may be useful to the administrator but is of much less value to the individual or to the physician who is interested in progressive medical science. From the point of view of the patient or the medical scientist, prognosis should be based on biological parameters rather than measures of prevalence or incidence. The probability of moving from a healthy or disease state to another is fundamentally dependent on individual biological parameters. Theoreticians (14,27,37) have postulated conditions or criteria that health indices should meet. Some of these criteria are so practically oriented that their indiscriminate adoption might inhibit the exploration of new possibilities. The condition that an index of health must be made of measurable components (37) is necessary but not sufficient. The measurable component must also be as directly related to health as is possible. Failure to realize this conceptual thrust encourages the tendency to select indicators on the basis of measurability rather than of strict and positive relationship to health. The deficiencies of mortality rates as indicators of health are good examples to illustrate that the use of surrogate indicators does not reduce the need for the continuous search for indicators that have higher validity with respect to what is to be measured, that is, health. Many investigators treat health and disease as complementary concepts. Even if it could be proven that they are, the “totality” of health is not known. The same “amount” of disease may have quite different consequences in two individuals, depending on the status of health of each individual. Freedom from disease is not equivalent to health. From a methodological standpoint, it will always be a weak philosophical approach to try to define things by what they are not rather than by what they are. It has been said (27) that at present the occurrence of illness and premature death are more compelling events in deciding the allocation of resources than the consideration of positive health. This is true, but it can only be accepted as a good argument for policy-making if it can be shown that the maintenance of such an attitude is accompanied by a continued rise in health benefits, for example, a

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reduction in mortality. A recent analysis of mortality rates in the United States (27) indicates that mortality from chronic diseases and accidents is likely to sustain the death rate near its present level until major advances are made in the control of death from these two causes. It is difficult to imagine that progress in the control of chronic disease may result from efforts other than medical and environmental research. On the other hand, the predictive aspect of any index of health can be improved only if disturbances in function, structure, and adaptation that herald disease are identified in man as early as possible. The weaknesses of indices based on mortality have been pointed out by several investigators in the field, and desirable criteria for “health” indicators have been proposed (27,32,37). Most of the proposed criteria deal with practical considerations pertaining to the collection and processing of data, to the comprehensibility of the models and interpretation of results, and to the adequacy of their utilization in connection with specific purposes. Unfortunately, the criteria for indices of “health” proposed thus far do not include any dimension of health. This deliciency exists because measurements or indices of health can most probably only be obtained from the individual. Measurement of individual and of social health may require different approaches even though the two are clearly related. If health could be measured for each individual, the assessment of community health would certainly be simplified. The hypothesis that the health of a community should be considered as an “emergent” phenomenon (22), a whole whose properties cannot be predicted by merely referring to the properties of the parts, is one that should be considered. To be accepted, though, this hypothesis will have to be proved, and this means that it will be necessary to measure individual health as well as community health. If, as Fig. 1 suggests, the measurement of health must be based on characteristics of the organismic system in relation to the natural and social environments, then the measurement of health requires: (a) the identification of the environmental factors which affect health; (b) the determination of the range of variation of these factors within which life is possible; (c) the study, in quantitative terms, of the physiologic, biochemical, and psychic responses to changes and rates of change in the environment; and (d) the study of the adaptability of the individual to the environment, that is, the human capacity to realize physiological, structural, and mental adaptive changes to stressful changes in the environment. The conditions in the environment that are necessary for the existence of life (the presence of oxygen, carbon dioxide, solar radiation, moderate temperature, and water) must, of course, be satisfied. However, higher forms of life are subject to physical factors and variations of those factors which are narrower than those for lower forms of life. The physical factors which affect human health, including temperature, light, noise, vibration, acceleration, atmospheric pollution by gases and particles, water pollution, and radiation, must also be considered. To these physical factors one must add biological factors in the form of microorganisms or nutrients and the psychosocial factors that with increasing influence are making an impact on each personal life. Thus, in that which concerns man, the organismic system, the dimensions of health are structural, physiologic, biochemical, and psychic.

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An up-to-date concept of health should be based on the study of human performance in response to a variety of physical and nonphysical factors. Total human performance can be described in terms of: (a) the capacity to perform certain functions, (b) the optimality with which these functions can be performed, considering the state of the organism, and (c) the adaptability of the organism to environmental changes. Thus, from the standpoint of capacity, man can be characterized by a profile of his abilities and inabilities, by his capacity for physical work, by his functional reserves, and by his responses to physical and psychosocial stimuli. From the standpoint of optimality, man can be characterized by the efficiency with which he is able to fulfill physiological and psychological functions, by modalities of functional regulation, by development of functional hierarchies, and by the mechanisms of adjustment to the environment (4,5,35). From the standpoint of adaptability, man can be described in terms of his potential to learn new things, to overcome physical incapacity, and to adapt himself to the everexpanding world in which he lives. Structural integrity is normally associated with good health, but lack of structural integrity does not necessarily imply disease. One of the most encouraging efforts in present clinical research is the application of scientific knowledge and modern technology to overcome disability in the presence of structural and functional deficiencies. Physiologic performance is, indeed, a major indicator of health. Studies of functional capacity at the motor, sensorial, and psychic levels are possible today with satisfactory testing procedures (1,6,8). The periodic administration of these testing procedures is proving to be of great value in providing an objective description of the process of aging. One of the most obvious manifestations of aging is the decline in the ability to exercise and do work. Since the rate of deterioration in the process of aging differs from one individual to another (30,34), measurements of the rate of deterioration in relation to age could be correlated with the prevalence and incidence of disease and thus be validated as possible measures of)health and as predictors of morbidity. Exercise testing is a good means of evaluating the total cardiorespiratory fitness of an individual (34). Other quantitative tests, facilitated greatly by modern technology, are available for assessing muscular strength, range of articular motion, nerve conduction velocity, hepatic and renal function, vision acuity, and hearing ability. Adaptation to short and prolonged changes in the environment constitute another parameter of health. Procedures to test the adaptability of the various organ systems of the body have not progressed equally fast for each system or organ but are available for many of them. The medical concerns created by the exploration of space by man have been a great incentive to the development of new testing techniques in this regard. From a biochemical standpoint, it has been amply documented that, as far as the biochemical parameters used in clinical evaluations are concerned, there is a high degree of uniqueness of each individual (42). Much, then, is to be gained in developing a methodology for the determination of human health that compares the individual with himself rather than with a usually undefined population. It

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should be recognized that normalcy and health are not equivalent concepts. Normalcy is a statistical concept, whereas health is a biological one. In terms of health, to compare an individual with a population norm is practically senseless when, for the parameter considered, the intraindividual and inter-individual variations over time are both relatively large. It has been suggested that for each individual the range of values of any blood constituent established during a period of optimum health is a better reference state than the statistical values obtained in population samples (43). In the dimension of mental health, it has been suggested (16) that indicators of positive mental health should be sought: (a) in the attitudes of an individual toward his own self, (b) in what a person does with his self over a period of time; (c) in a central synthesizing psychological function recognizable in each person; (d) in the individual’s degree of independence from social influences; (e) in the adequacy of an individual’s perception of reality; and (f) in the individual’s capacity for environmental mastery. The extent to which these indicators can be used to formulate expressions of mental health that can be quantitated according to an appropriate scale is not clear at this time. On the other hand, the two-way relationship of mental processes of somatic function is an open field for investigation, although some of its aspects are presently attracting the attention of able investigators (9,171.

It has long been surmised that genetic endowment is a major determinant of health. The relationship between the genetic make-up and certain diseases is not in doubt; but we are just beginning to understand the basic nature of this relationship. Although it is only logical to assume that, if genetic factors relate to disease, they must also relate to health, we have not yet reached the point where genetic indicators of positive health have been identified. An investigation of such genetic factors and of their interaction with the physical and psychosocial environments is one of the major and promising tasks in health research. An interesting step toward using biological parameters and other risk factors to predict disease has been made at the Preventive Medicine Institute-Strang Clinic of New York (25) and as a result of the Heart Disease Epidemiological Study conducted in Framingham, Massachusetts. The Framingham study resulted in a collection of data that permitted the calculation of the probability of developing coronary heart disease in 6 years in relation to seven risk factors: sex, age, cigarette smoking, arterial blood pressure, serum cholesterol, glucose tolerance, and electrocardiographic abnormalities. IMPLICATIONS

FOR HEALTH SYSTEMS

PLANNING

A system is usually conceived as an aggregate of elements or components linked by some form of interaction so as to perform a specific function. The application of this definition to a health care system requires the description of the functions of the system, the components of the system, and the interaction among components. The functions of a health care system were amply reviewed in the first IIASA conference of 1974 (40). These are: (a) medical research and accumulation of medical knowledge; (b) comprehensive individual and community measures for prevention of disease, with special emphasis on infant and child care and en-

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vironmental health; and (c) timely diagnosis of diseases and their adequate treatment and cure. It should be recognized that not all the health care systems that exist, or are being planned, are capable of fulfilling all these functions (31). However, not all the functions that a health care system should fulfill are mentioned above. If we admit that health can be improved as well as impaired, that disease can be resisted, and that the process of natural biological deterioration has a different tempo for different individuals and perhaps can be retarded, then the promotion and restoration of health, the early detection and prevention of disease, and the rehabilitation of the physically and sociogenically disabled must be part of the functions to be fulfilled by a health care system. In particular, studies aimed at the identification of determinants of positive health should be part of the research goals of health care systems. The identification of determinants of positive health should provide the basis for a predictive medicine. Predictive medicine must be conceived as the measuring stick against which the effectiveness of preventive measures can be assessed. It is widely recognized that one of the major goals of a health care system is the prevention of disease. The promotion of health should also be added. It is, therefore, of paramount importance that, in planning health care systems, the concept of positive health not be overlooked. REFERENCES 1. Bell, B., Rose, C. L. and Damon, A. The formative aging study: An interdisciplinary and longitudinal study of health and aging. Aging Human Deve/op. 3, 15-17 (1972). 2. Berg, R. L. Weighted life expectancy as a health status index. Healfh Serv. Res. 8, 153-156(1973). 3. Breslow, L. A quantitative approach to the World Health Organization definition of health: Physical, mental and social well-being. Int. J. Epidemiol. 1, 347-355 (1972). 4. Cardus, D. Towards a medicine based on the concept of health. Prev. Med. 2, 309-312 (1973). 5. Cardus, D. Implications mediques d’una nova approximaci6 al concepte de salut. (Medical implications of a new approach to the concept of health) An. Medi. Acad. Cienc. Mbdi. CataluAa y Baleares, 507-537 (1973-1974). 6. Comfort, A. Test-battery to measure aging-rate in man. Lancet 2, 1411-1415(1969). 7. Chiang, C. L. How to measure health: A stochastic model for an index of health. Inr. J. Epidemiol. 2, 7-13 (1973). 8. Damon, A. Predicting age for body measurements and observations. Aging Human Develop. 3, 169-173 (1972). 9. Dicara, L. V. Learning of cardiovascular responses: A review and a description of physiological and biochemical consequences. Trans. N. Y. Acad. Sci. 33, 411422 (1971). 10. “Dictionary of Scientific and Technical Terms.” McGraw-Hill, New York, 1974. 11. Dolfman, M. L. Toward operational definitions of health. J. Sch. Health 44, 206-209 (1974). 12. Engel, G. L. A unified concept of health and disease. Perspect. Biol. Med. 3,459-485 (1960). 13. Fanshel, S., and Bush, J. W. A health-status index and its application to health-services outcomes. Operations Res. 18, 1021-1066(1970). 14. Gentry, J. T., and Mathews, J. S. Health service indicators as components of a health status index. Health Serv. Res. 8, 14-16 (1973). 15. Goldsmith, S. B. The status of health status indicators. Health Serv. Rep. 87, 212-220 (1972). 16. Jahoda, M. “Current Concepts of Positive Mental Health.” Basic Books, New York, 1958. 17. Kagan, A. R., and Levi, L. Health and environment-psychosocial stimuli: A review. Sot. Sci. Med. 8, 225-241 (1974). 18. Kessner, D. M., Kalk, C. E., and Singer, J. Assessing health quality-The case for tracers. N. Engl. J. Med. 288, 189-194 (1973).

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19. Kisch, A. I., Kovner, J. W., Harris, L. J., and Kline, Cl. A new proxy measure for health status. Health Serv. Res. 4, 223-230 (1969).

20. Krall, J. M. An index of health: An application in accidents. Management Sci. 18, B744-B749 (1972). 21. Lawton, M. P., Ward, M., and Yaffe, S. Indices of health in an aging population. J. Gerontol. 22, 334-342 (1967). 22. Lerner, M. Conceptualization of health and social well-being. He&h Serv. Res. 8, 6-12 (1973). 23. Merrell, M., and Reed, L. J. The epidemiology of health, in “Social Medicine, Its Derivations and Objectives” (I. Goldston, Ed.), pp. 105-l 10. The Commonwealth Fund, 1949. 24. Meshenberg, M. J. “Health Planning and the Environment: A Preventive Focus,” p. 105. American Society of Planning Officials, Chicago, 1974. 25. Miller, D. G. Preventive medicine by risk-factor analysis. JAMA 222, 312-316 (1972). 26. Miller, J. E. An indicator to aid management in assigning program priorities. Public Health Rep. 85, 725-73 1 (1970). 27. Moriyama, I. M. Problems in the measurement of health status, in “Indicators of Social Changes” (E. B. Sheldon and W. E. Moore, Ed.), pp. 573-600. Russell Sage Foundation, Newmark, 1968. 28. Patrick, D. L., Bush, J. W., and Chen, M. M. Toward an operational definition of health. J. Health Sot. Behav. 14, 623 (1973). 29. Patrick, D. L., Bush, J. W., and Chen, M. M. Methods for measuring levels of well-being for a health status index. Health Serv. Res. 8, 228-245 (1973). 30. Premature ageing syndromes, (Editorial). &it. Med. J.. p. 489 (November 30, 1974). 31. Purola, T. A systems approach to health and health policy. Med. Care 10, 373-379 (1972). 32. Sanders, B. S. Measuring community health levels. Amer. J. Public Health 54, 1063-1070(1964). 33. Sheldon, A. Toward a general theory of disease and medical care. Sci. Med. Man 1, 237-262 (1974). 34. Shock, N. W. The physiology of aging. Sci. Amer. 206, 100-l 11 (1962). 35. Spencer, W. A. Changes in methods and relationships necessary within rehabilitation. Arch. Phys. Med. Rehab. 50, 566-580 (1969).

36. Stouman, K., and Falk, I. S. Health indices: A study of objective indices of health in relation to environment and sanitation. Bull. Health League Nations 8, 63 (1939). 37. Sullivan, D. F. Conceptual problems in developing an index of health. National Center for Health Statistics, Series 2 (17): l-18 Washington, D.C., (May) 1966. 38. Sullivan, D. F. A single index of mortality and morbidity. Health Serv. Mental Health Admin. Health Rep., 86 (4): 347-354 (1971). 39. Torrance, Cl. W., Thomas, W. H., and Sackett, D. L. A utility maximization model for evaluation of health care programs. Health Serv. Res. 7, 118 (1972). 40. Venediktov, D. D. Systems analysis of health services, in “Systems Aspects of Health Planning. Proceedings of IIASA Conference, Baden, Austria, August 20-22, 1974” (N. T. T. Bailey and M. Thompson, Eds.), pp. 19-30. 41. “Webster’s Third New International Dictionary.” G. & C. Merriam, Springfield, Mass., 1971. 42. Williams, G. Z. Unique characteristics and implications of individual health profiles. MCV Quart. 9, 355-359 (1973). 43. Williams, G. Z. Individuality of clinical biochemical patterns in preventive health maintenance. J. Occup. Med. 9, 567-570 (1967). 44. “World Health Organization. Measurement of Levels of Health. Report of a Study Group,” World Health Organization Technical Report Series, No. 137. World Health Organization, Geneva, 1957. 45. Wylie, C. M. The definition and measurement of health and disease. Pub. Health Rep. 85, 100-104 (1970).

Overview: health and the planning of health care systems.

PREVENT,VE MEDIC,NE 6, 134~ 142 (1977) Overview: Baylor Health and the Planning Systems’ of Health Care DAVID CARD& AND ROBERT M. THRALL Col...
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