Monday, April 05, 2010

EVIDENCE-BASED HEALTH SCIENCE: DOUBLEPLUSUNGOOD

I am no homeopathy sympathiser, but the parameters of the recent debate about whether it should receive public funding have been depressingly narrow, not to mention bullying. The winning argument was that homeopathy is no more effective at treating particular complaints than a placebo. The lack of an "evidence-base" led health scientists to denounce homeopathy as no more than new-age quackery.

The reputation of homeopathy will not have helped its cause. It represents everything that the dominant philosophy of health science opposes: it is subjective, where health science is objective. It fails miserably in the laboratory, though even its fiercest critics acknowledge that many people have felt healthier after using it.

So we have here a paradox. It seems reasonable that we should not pay for something for which there is no evidence; and yet homeopathy does appear to work for many people. What, therefore, does one mean by "evidence"? Can "blind faith" in medicine ever be scientific? What is the nature of truth in this kind of debate?

In 1993, the Cochrane Collaborative developed a database to bring together research which demonstrated the effectiveness of particular interventions. Research is eligible for inclusion if it is based on randomised-controlled trials (RCTs); any other form of enquiry - e.g. empirical or naturalistic research using real patients in the clinic - is excluded.

I have written before about the distorting effects of RCTs. In order to test something objectively, external factors (such as the quality of the clinician, any co-morbidities which the patient might present, genetic predispositions etc) must be removed. For example: to test whether a particular psychotherapy is effective in treating depression in comparison to, say, an antidepressant, all research subjects must be as identical as possible. Everybody must have similar levels of depression, nobody can have panic disorder, because their panicky symptoms might warp the trial. The research also must not allow any form of relationship to develop between the patient and their therapist or doctor, as this might also compromise the objectivity of the trial. The problem is, something like 50% of people with clinical depression also have other neurotic disorders (and all will come into contact with a medical professional).

The evidence-based health science (EBHS) movement has no truck with this. The RCT has become the gold standard of research, to the exclusion of other approaches. "In the starkest terms," explain the authors of this deconstructive critique of EBHS, "we are currently witnessing the health sciences engaged in a strange process of eliminating some ways of knowing."

The hegemony of EBHS has also sterilised debate in health science:

an unvarying, uniform language – an ossifying discourse – is being mandated in a number of faculties of health sciences where the dominant paradigm of EBHS has achieved hegemony. This makes it difficult for scholars to express new and different ideas in an intellectual circle where normalisation and standardisation are privileged in the development of knowledge.

In recent years, the National Institute of Health and Clinical Excellence (NICE) has, on the basis of RCT research, recommended variants of Cognitive Behavioural Therapy (CBT) for virtually all neurotic disorders, and disregarded other therapies which are less amenable to RCTs. But rather than arguing their case within different parameters of debate, psychoanalysts have agreed to test their approach via RCTs. If this allows a broader choice of therapies to be available on the NHS, it must be welcome (though one wonders if the RCTs do not find psychoanalysis to be effective, whether psychoanalysts will all retain as Cognitive Behavioural Therapists...).

Such are the confines of positivism. Truth is alienated from subjectivity; it is "out there," independent of the observer, waiting to be grasped, an eternal aggregate of a priori facts which cannot be remoulded by new events. The word used by the deconstructionists - "ossified" - is spot on, and although at times they do not care to admit it, theirs is a materialist critique, in that it admits that ideas and abstractions must derive from lived experience.

This applies to EBHS itself. It is a political doctrine which believes - in the words of Hannah Arendt - that it "can explain everything and every occurrence by deducing it from a single premise." Because that single premise is "out there" and objective, it needs a different language to describe it. Here the deconstructionists recall the Orwellian language of Newspeak. Language is reduced to its most monochromatic basic units; synonyms are eradicated, and what's left behind is radically redefined. In EBHS, "evidence" is the only word used to describe exercises which demonstrate medical effectiveness, yet "evidence" only means "RCT." In other words, naturalistic clinical trials which show that an intervention works cannot be classified as evidence which, so the logic goes, means the intervention cannot be effective.

This is lazy, paradoxical thinking:

The mastery of scientific Newspeak is, for the most part, a regurgitation of prefabricated formulas (buzz words or catch words) that is informed by a single, powerful lexicon. This new guide book of scientific vocabulary, including terms connected with evidence-based medicine (e.g. systematic literature review, knowledge transfer, best practices, champions, etc.), is taken seriously in the realm of health sciences, so much so that it is considered vital as a reflection of ‘real science’.

The British Government's rhetoric of evidence-based healthcare and "patient choice" (themselves often contradictory) will increasingly be compromised by brutally-cut health budgets. The stories about people with dementia who are denied certain cholinesterase inhibitors because they are too expensive will begin to be replicated amongst people with non-terminal illnesses too. But just as in hard times the conventional economic wisdom of applied mathematics is supplanted by the subjective experience of people on the dole or striking to protect their wages, so patients can fight the doctrinaire ideas of the EBHS movement with a demand that their opinions about what might help them get better may be just as relevant as the opinions of their doctor.

"Plurality," says Hannah Arendt, "is the condition of human action because we are all the same, that is, human, in such a way that nobody is ever the same as anyone else who ever lived, lives, or will live." Such pluralism is constantly under threat in a capitalist society, which seeks to reduce us to consumers (even of healthcare). But when that capitalist society becomes vulnerable, there is suddenly the space for individual voices to be heard, and for the collective voice to win through. Not the collective voice of the objective, the abstract or the mean, but of "an honest plurality of voices [which] will open up a space of freedom for the radical singularity of individual and disparate knowledge."

1 Comments:

Anonymous Health Science said...

I thought I'd ask you guys for an advise. I am an incoming freshman student. What's the best med school here on the pacific? Thank you and more power!

9:01 AM  

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