Monday, October 16, 2006


I have not yet commented on the latest Lancet report of huge post-invasion mortality ("about 655,000" extra deaths) in Iraq as it seemed perfectly obvious from the outset to me and to many others that it was just a piece of agitprop that would have done the old Soviets proud. You would have to be a Leftist to believe that nobody else noticed 655,000 corpses. I have googled up quite a few comments on the study now, however, and I have not so far found anybody who has noticed the really glaring defect in the study.

None of the comments I saw appeared to be by people who are experienced users of cluster sampling -- the method used for the Lancet study. I am a VERY experienced user of cluster sampling -- with many of my academic publications based on it. And the glaring error which rather explains why the study appeared in a medical journal rather than a more statistically sophisticated journal is that there was NO VALIDATION of the survey results. That your survey-takers might just sit down under a tree and "make up" their "interview" results is a routine peril and it is routine to take precautions against it -- usually by going back on a later occasion and checking with the alleged respondents a proportion of all interviews handed in. Just the awareness that a sample of the respondents will be re-interviewed tends to keep the interviewers honest -- though not always so, regrettably. So the results reported in the Lancet study have no credibility at all and must be regarded as garbage.

It is astounding that the authors of the study were so naive. Perhaps they WANTED their interviewers to "fudge" the results -- making clear what the desired results would be, of course.

Another oddity in the Lancet article that suggests something peculiar about the authors is the claim that their interviewers were all DOCTORS -- and not just any doctors but doctors bilingual in Arabic and English. I have never seen the like of that before. Experienced interviewers of some kind were what was needed and that is what is usually used, not doctors. Can we really believe that a whole corps of these rare doctors abandoned their medical duties for so long in order to do something outside their normal expertise? If true it certainly suggests a heavy political committment on the part of the doctors concerned -- exactly what one would NOT want in a study claiming to be objective. To me the whole claim seems like the sort of "gilding the lily" that con-men engage in.

Other critics have noticed other vast implausibilities in the results reported -- the amazingly high (98%) success-rate at getting people to consent to an interview, for instance --- garbage, garbage garbage. And the lie about the death certificates actually shows how bogus the results were.

I wonder what my old friend the Liberal Avenger will make of this post? He is firmly convinced that no sound criticism of the Lancet study can be made. I predict much huffing and puffing from him. I know the sort of thing he will say: That doctors ARE experienced interviewers, for instance. He has however never been door-to-door if he thinks people respond to doorstep callers the way they respond to a doctor they go to.


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