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Cadernos de Saúde Pública

On-line version ISSN 1678-4464Print version ISSN 0102-311X

Cad. Saúde Pública vol.17  suppl.0 Rio de Janeiro Jan. 2001 


Maurício L. Barreto

Instituto de Saúde Coletiva, Universidade Federal da Bahia.

Debate on the paper by David Waltner-Toews

Debate sobre o artigo de David Waltner-Toews



Interventions in the environment and society in the quest for health: how scientific can we be?


There is no doubt that one of the current characteristics of many scientific fields is to seek all-encompassing models capable of providing more convincing and useful explanations for the phenomena under study. No matter how much I reflect on the notion that science can develop itself on its own strengths, I take a firm stand with those who view science as fundamentally tied to the search for solutions to concrete problems, even though this may require investigative projects in the short, medium, long, and very long terms. Such effort can be understood as one of the most useful exercises in strategic planning, and as such the undertaking entails risks, since of course part of the effort fails to materialize in the form of actual products. At any rate, we may always ask: a solution to what? a solution for whom? The article under debate aims a cutting but fair critique at the biomedical models flourishing around disease. In such models the idea of health, no matter how embellished it may be, is never understood beyond the notion of cure (or prevention of disease at most). Such models are hardly useful whenever one thinks of health as something positive (and here it is unnecessary to repeat the well-known WHO definition) rather than as the mere absence of disease. If we do think along these lines, we can only ask what should be done by all those who criticize, find fault, or even abhor such models? Of course this question is asked frequently, but the answer is not at all easy (Barreto, 1998). For example, in a recent review of the child health issue, Ehiri & Prowse (1999) discuss the extent to which preventive and promotional programs reflect the Western medical care model, with little emphasis on child health's environmental and social dimensions, even though it is the object of extensive discussion and apparent consensus.

The biomedical model is reaffirmed daily by immense research and intervention structures, based on an enormous and lucrative industrial and services framework, worshipped by many, but considered scarcely useful and even iatrogenic by (a few) others. Considering the scientific research component alone in the United States, the National Institute of Health alone invests 14 billion dollars a year. But we do not have to look that far for examples, since in Brazil the scarce resources for health allocated through the Ministry of Health and its affiliated institutions basically serve to reaffirm this same Western biomedical model.

With recent advances in molecular genetics, more than a few believe that human ills (including health problems) are located in the genes and the molecules coded by them. For those who so believe, issues like the environment, society, and other blah-blah-blahs are merely ideological elements that feed the political action of a handful of upstarts, or in a more useful way, when properly presented, to serve as an enticing introduction to the discourse of even the very proponents of the biomedical model. This reminds us of Pasteur's Revolution, a transcendental moment in the progress of scientific knowledge; however, when it was contextualized within the philosophical hue of Positivism it transmuted the idea of microbial causality of disease (a huge step forward in late 19th-century scientific knowledge) into dogma, a fact with repercussions that are still felt today and that have hampered (if not completely impeded) other approaches to health and human diseases. An analysis of recent advances in biology and molecular genetics shows how these fields have spawned a new revolution in knowledge of the human body, but that they have simultaneously fed a growing legion of ideas that once again seek to reduce human health to its biological determinants, considering discussions of man and the environment or man and society as merely ideological, with no scientific basis.

The paper currently under debate touches on these and other discussions and proposes a model, the "ecosystem approach", which is certainly appealing since it "brings together the socioeconomic and biophysical approach to health". Obviously, if the biomedical model currently predominates when the issue is knowledge concerning the causes of health and diseases, what can we expect from the interventions to be conducted vis-à-vis supposedly known problems? A question that remains to be answered is whether we can propose effective and scientifically sound interventions without a clear causal model for health problems. Elementary scientific logic tells us that when we intervene in reality we must avail ourselves of reasonable models on which to test the intervention, but that each intervention also needs to be empirically tested. Herein lies an imperfection left by incomplete scientific progress, that is, the scarcity of resources for evaluation of interventions. If we now sometimes spend decades discussing whether a given vaccine is effective, we can only imagine tackling the daunting task of evaluating a complex and much less clearly outlined intervention as proposed under the "ecosystem approach".

Of course the ideas laid out here may suggest a paralyzing and backward-thinking type of "scientism", as opposed to the "progressivism" of the "ecosystem approach". No, I would never think that actions should necessarily be governed from beginning to end by scientific rationality, as indeed is the status that the "ecosystem approach" seeks. However, I believe that interventions in human populations are politically defined, with a greater or lesser degree of rationality and scientific basis. There is no doubt that human health underwent interventions before scientific knowledge existed, and sometimes even with great success.

In short, I do not believe that we have "scientific" answers to many of the main issues affecting human health. We know that many things are wrong, we share in the criticism contained in the paper, and we agree with the urgent need to "address the flaws in reasoning and tactics we have employed to date". However, all this serves more to orient the agenda for a scientific program and less to orient scientifically based interventions. Meanwhile, there is a wide range of evidence suggesting that changes are needed in society and the environment to achieve better health standards, but that this agenda is far from being defined in merely scientific terms. At most, the sciences in their current stage can provide clues for politically organized societies to choose the best actions, or sometimes the lesser of two evils, with a view towards solving their health problems. It was no coincidence that the report by an expert committee named by the UK Ministry of Health to recommend policies for reducing existing health inequalities noted that interventions in this field had rarely been submitted to controlled evaluation methods; however, this did not keep the committee from seeking its own alternatives in order to issue opinions on the effectiveness of existing health interventions and thus offer scientifically based alternatives to bolster the country's social health policies (Acheson et al., 1998). Some believe that epidemiology's multifactorial causal models only serve as a counterpoint to traditional biomedical models when they are based on the idea that health (as a biologically based event) is, in the final analysis, a social phenomenon (Tesh, 1998) and that in order to be effective, proposals generated from the perspective of social epidemiology must seek not only scientific support but above all social and political backing (Heymann, 2000).



ACHESON, D.; BARKER, D.; CHAMBERS, J.; GRAHAM, H.; MARMOT, M. & WHITEHEAD, M., 1998. Independent Inquiry into Health Inequalities. London: The Stationery Office.

BARRETO, M. L., 1998. Por uma epidemiologia de saúde coletiva. Revista Brasileira de Epidemiologia, 1:104-130.

EHIRI, J. E. & PROWSE, J. M., 1999. Child health promotion in developing countries: The case for integration of environmental and social interventions? Health Policy and Planning, 14:1-10.

HEYMANN, S. J., 2000. Health and social policy. In: Social Epidemiology (L. F. Berkman & J. Kawachi, eds.), pp. 368-382, New York: Oxford University Press.

TESH, S. N., 1988. Hidden Arguments: Political Ideology and Disease Prevention Policy. New Brunswick: Rutgers University Press.