Epidemiologic methods: Beyond clinical medicine, beyond epidemiology

Francisco Bolumar1 & Miquel Porta21Universitat Miguel Hernandez, Alacant, Spain; 2 Institut Municipal d’Investigacio Medica and Universitat Autonoma de

Barcelona, Spain

Accepted 9 June 2004

The truth likes to hide

out in the open.Anne Michaels [1]

Professor Olli S. Miettinen is one of the mostinfluential epidemiologists of the 20th century, andhis legacy continues to be felt deeply in epidemio-logic reasoning today [2, 3]. He is one of the veryfew whose class notes have been widely quoted inmajor textbooks [4]. His influence has been vast infurthering new methodological approaches to clini-cal and public health problems; this has occurredlargely through the work of others, i.e., throughsubsequent reinterpretation of his often obscurewords.

Thanks to the work of colleagues such as OlliMiettinen and many other, today research methodswith strong epidemiological roots are widely andfruitfully applied ‘within’ and ‘outside’ epidemiology.The epidemiological roots are obviously historical, aswell as epistemological and ontological. Withoutmuch threat to epidemiologic ‘‘coherence’’ and‘‘cohesion’’ that we are aware of, Miettinen’s workhas contributed to a positive blurring of the borders ofepidemiologic research methods; e.g., to the integra-tion of population thinking into clinical and publichealth research [5–9]. The expansion of this influencetowards other research areas remains a significant – inour view, highly attractive – challenge for many epi-demiologists [10]. Such an expansion of influence willnot be identical to what occurred via ‘‘clinical epide-miology’’ and, later, ‘‘evidence-based medicine’’. Thenature of the hypotheses at stake is often quite dif-ferent in clinical medicine than in, say, molecularbiology or genetics; largely because of this ontologicalfact, epidemiologic thinking continues to create newapproaches, research designs, strategies of analysisand ways to assess causality for such biological dis-ciplines [5, 6, 11–15]. Furthermore, we believe that thehorizons of the present debate on Miettinen’s paper[16] should also include the contributions of epidem-iologic methods to research on those public healthproblems that are best tackled by blending the rea-soning and the tools of epidemiology and of some ofthe social sciences [17–20]. We find little of this in thepaper under discussion [16]: in our view it is toonarrowly centered on the relationships between tra-ditional or classic epidemiologic research and research

in clinical medicine; it speaks to epidemiologistsalmost as if we (they) were closed in a church undersiege; and it barely refers to the important methodo-logical advances that are already favoring the inte-gration of epidemiological methods into ‘‘micro-biological’’ and ‘‘macro-social’’ health research [10].This first comment thus refers to the limits of theideological framework chosen by the author [16].

Within that framework, Miettinen makes anumber of sound criticisms (e.g., on the role ofstatistics, the importance of the study base, theneed for a stronger scientific basis of medicine, theconfusion between screening and prevention, theimportance of ‘‘intrainstitutional iatrogenesis’’).Yet, we have not been able to discern very manyinnovative proposals in the text. For instance, theidea that there is a ‘‘need to leave behind theconcepts of ‘‘cohort’’ study and ‘‘case–control’’study’’ and to ‘‘adopt that of the etiologic study asthe singular substitute for these’’ [16] does not seemto go beyond the well-known rationale for nestedcase–control, case-cohort and related designs [21].Assessing etiologic relationships is a fundamental,common, and well-known aim of several epidemi-ologic research designs. As far as we can tell, notmany colleagues would dispute the notion thatmost ‘‘intervention research’’ can be thought to fallwithin the domain of etiologic research – butMiettinen’s references provide few clues, if any, asto who would argue otherwise.

The idea that methods must be coherent with theobject of the study seems hardly new, either. Ofcourse, it would not be hard to find examples of poorstudies – epidemiologic and otherwise – that over-looked such need; e.g., studies suffering from ahypertrophy or a dissonance of the methodologicalapparatus vis-a-vis the study hypotheses; or studiesbased on a poor conception of the hypotheses; orstatistical analyses unguided by knowledge availableon the study subject [22, 23]. Should we really thinkthat epidemiologists are the only scientists that needto ‘‘become serious about object design’’ [16]? This isan ancient and elemental principle for any scientist.Without a careful attention to it, the many contri-butions of epidemiology to knowledge on humanhealth would not have happened.

European Journal of Epidemiology 19: 733–735, 2004.� 2004 Kluwer Academic Publishers. Printed in the Netherlands.

Also within the landscape of epidemiologic meth-ods, the paper [16] seems to overlook at least some ofthe most important advances that have been made inthe recent past [24–31]. There is barely any recogni-tion of contributions made by others.

Time has shown that the mind of Olli Miettinenmay hold treasures. It is hence unfortunate that hisstyle of writing ‘‘speaks for itself’’: cryptic, tortuous,enigmatic… Miettinen has long seemed to rejoice inthis.

His is not a text that many clinicians will care tounderstand. Miettinen states that ‘‘only we [‘‘researchepidemiologists’’] can assume the central role in theproduction of the knowledge base for scientificmedicine’’, and that ‘‘we consequently have theobligation to assume this larger and higher, meta-epidemiologic mission’’. The paper refers severaltimes to the ‘‘uniqueness’’ of ‘‘us epidemiologists’’, toa ‘‘mission’’, ‘‘obligation’’, ‘‘vision’’, ‘‘dream’’,‘‘devotion’’… It is unimportant that the languagesounds too ecclesiastic to us. We simply find suchpropositions at odds with much of the contemporaryscientific world: wide open, transdisciplinary – muchmore creative, relevant, efficient, and interesting be-cause of the porousness, flexibility and adaptability ofthe disciplines than because of the putative highermission of their clerics and disciples.

It is almost certain that epidemiology wouldbenefit from a stronger philosophical base, includ-ing epistemology and ontology. As it would benefitfrom a proper ‘sociology of epidemiology’ [10].What we are not sure of is whether we are loosinga great expert in scientific methods while reallygaining a philosopher of epidemiology. It wouldhave been too easy to title this commentary ‘‘Quovadis, Olli Miettinen?’’.

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Address for correspondence: Miquel Porta, InstitutMunicipal d’Investigacio Medica, UniversitatAutonoma de Barcelona, Carrer del Dr. Aiguader,

80 E-08003 Barcelona, SpainPhone: +34-93-225-7550/221-1009; Fax: +34-93-221-3237E-mail: mporta@imim.es

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