Toward a Practicable Methodology for Medicine: The Impact of Conceptual Analysis

TOWARD A PRACTICABLE METHODOLOGY FOR MEDICINE: THE IMPACT OF CONCEPTUAL ANALYSIS WIMJ. VAN DER STEEN* Introduction Will biology suffice as a base of medical science? Does medicine need a hermeneutical in addition to a scientific approach? Are concepts of health and disease value-neutral? How should medicine deal with the mind-body problem? Questions as broad as these are typically the ones that are addressed in the philosophy of medicine. Indeed the importance of such questions is obvious. Philosophy of medicine has been less concerned with methodological analysis of concrete science that finds its way into medical journals. (I am using the term "methodology" for philosophical, not statistical methodology.) I will argue that the balance needs to be redressed. An analysis of concrete science should precede the elaboration of general views concerning the role of science in medicine . Elsewhere I have surveyed methodological tools which fit this purpose [1—4]. Here I concentrate on tools for the analysis of concepts in medicine. Methodology is not high on the agenda in medical science. Epidemiology is one of the few areas in medicine where methodology plays an explicit, albeit minor, role. Most philosophical efforts of epidemiologists have gone into a discussion of views on testability defended by the philosopher Popper [5, 6]. Specifically, there have been heated debates concerning the form which the principle of testability should take [7-16]. I will not present my own views of testability here. Instead I will concentrate on conceptual analysis since one cannot meaningfully discuss the testability of hypotheses and theories unless the concepts they contain are clear. I will show by examples, from psychiatry and allied *Faculty of Biology, Free University, De Boelelaan 1087, 1081 HV Amsterdam, The Netherlands.© 1993 by The University of Chicago. All rights reserved. 003 1-5982/93/3604-083 1 $0 1 .00 580 Wim J. van der Steen ¦ Methodology for Medicine areas, that a methodological analysis of concepts can have profound implications for medicine. The methodological tools I will use are relatively straightforward. They are meant as a practicable guide for researchers and practitioners in medicine. In addition to this I will show that the analyses have consequences for the philosophy of medicine. Etiology in Psychiatry Hypotheses in sound research are typically tested against alternatives. In the simplest case of statistical testing, a null hypothesis is pitted against an alternative which is its complement. The two hypotheses in that case represent a dichotomous classification which is exclusive and exhaustive. I will not elaborate this since statistical methodology is welldeveloped in medicine. Hypotheses are also formulated at more abstract levels connected with tests in an indirect way. Concerning those levels, methodology gets less attention. To deal with statistics does not suffice. In addition one needs philosophical methodology. This is illustrated by the following example. Schools in psychiatry attribute debilitating mental disorders to quite different causes. The currently dominant view of biological psychiatry emphasizes biological factors internal to the organism. The ultimate cause of the disorders is thought to be genetic. In other schools the emphasis is rather on psychosocial factors. Now even the most staunch defenders of biological psychiatry grant that environmental factors, in the sense of psychosocial factors, modify the influence ofbiological ones, but they relegate them to a subordinate position. Which side should one take in this controversy? My reaction is that it is unwise to take sides at all because the issues are phrased in methodologically inadequate terms [17, 18]. The following concrete example indicates what's wrong with the controversy. Schwartz and Africa, who argue that both biological and psychosocial factors are important, present the following classification of etiological factors for schizophrenia [19]. A Biological factors Al Genetic factors A2 Specific abnormalities A2a Anatomical and physiological factors A2b Biochemical factors B Psychosocial factors B 1 Development of the individual B2 Development within the family B3 Development within society and the larger environment B3a Population density Perspectives in Biology andMedicine, 36, 4 ¦ Summer 1993 | 581 B3b Socioeconomic class B3c Date of birth B3d Other factors Biological factors here obviously represent internal ones. That is, the concern of biology is assumed to be with processes inside the organism. External factors are placed in the domain of the...