Jim Giles talked to epidemiology experts about the Lancet study. (Nature subscription required):

Data from other conflicts show that such sampling is much more accurate than media reports, which usually account for no more than 20% of deaths. “Random counts force you to go to places that aren’t convenient,” says Jana Asher, a researcher with the Science and Human Rights Program of the American Association for the Advancement of Science in Washington DC. “The media don’t wander off to distant locations. It’s a very different type of data collection.”

Death tolls from Iraqi health officials, the source of US government figures, are also suspect. The Johns Hopkins team says that the process for issuing death certificates still works well in Iraq, but the system for monitoring the number of certificates issued does not. Even before the war, note the researchers, the government’s surveillance system captured only one-third of all deaths.


Yet despite the weakness of other measurements, the new figure has still surprised researchers. Perhaps the most significant concern is the baseline rate for pre-invasion death rates used in the new study. The latest survey, which included questions about the situation before the invasion, put this at 5.5 deaths per 1,000 people per year, in line with figures on Iraq from the US Census Bureau. Iran, which has a well-run health system, has a similar rate, but Iraq was at the time suffering from years of sanctions. Some sources, including the United Nations Population Division, list a pre-invasion figure of 9.7.

The discrepancy does not invalidate the new result, and if the researchers underestimated the pre-war death rate, it’s possible that they may have also underestimated the post-war rate. But some researchers say the paper should have addressed the issue. “There should have been more introspection,” says Beth Osborne Daponte, a demographer at Carnegie Mellon University in Pittsburgh, Pennsylvania. “That increased my discomfort.”

Other researchers share that discomfort. Debarati Guha-Sapir is director of the Centre for Research on the Epidemiology of Disasters in Brussels. She has some methodological concerns about the paper, including the use of local people — who might have opposed the occupation — as interviewers. She also points out that the result does not fit with any she has recorded in 15 years of studying conflict zones. Even in Darfur, where armed groups have wiped out whole villages, she says that researchers have not recorded the 500 predominately violent deaths per day that the Johns Hopkins team estimates are occurring in Iraq.

But overall Guha-Sapir says the paper contains the best data yet on the mortality rate in Iraq. And none of the experts contacted by Nature said that their doubts fatally undermined the study. Some, such as Daponte, would have liked the authors to have better assessed their method’s shortcomings before releasing a result with such political impact. But most say the result is a welcome addition to conflict epidemiology, which is now seen as playing a central role in assessing the severity of wars, and in helping states recover from them (see ‘Counting the cost of war’).

Burnham says he would now like to study patterns of migration in Iraq and the state of the health system. He would also like to estimate deaths based on a sample 4-5 times bigger than that used so far. But survey teams are in danger on the streets of Iraqi towns, and Burnham doubts whether the need for more detailed data justifies the risk.

Hat tip: Nexus 6

Comments

  1. #1 wacki
    October 19, 2006

    I don’t understand how this article matches the title. If the lancet study was off on prewar rates that can dramatically affect the “extra death” count.

    For instance, if pre-war invasion was 9.7 deaths / 1000 and post war invastion was 5.5 deaths /1000 than that is 4.2 deaths /1000 that are attributed artificially to coalition forces. Since iraqs population is 28,807,000 we can do some simple math.

    28,807,000 /1000 = 28,807 (groups of 1K people)
    28,807* 4.2 = 120,989.4 extra deaths artificially attributed to coalition forces for each year that the study includes.

    Please forgive me if I botched up some horribly simple statistics, but where is my line of reasoning wrong?

  2. #2 wacki
    October 19, 2006

    ugh….. I made a typo

    I meant if the UN prewar rates of 9.7 deaths/1000 are correct and the Lancetts prewar rates of 5.5 deaths/1000 are incorrect then that’s an extra 4.2 attributed to the coalition.

    My appologies for the confusion

  3. #3 Davis
    October 19, 2006

    Please forgive me if I botched up some horribly simple statistics, but where is my line of reasoning wrong?

    I’m not a statistics expert, but here are a couple of things to consider.

    (a) If their survey underestimated the pre-war death rate due to some sort of systematic error, then the post-war death rate would have a good chance of being similarly underestimated.

    (b) If the pre-war mortality really was 9.7/1000, say, and the post-war estimate was correct, then we’re still talking about large numbers. Bumping 120,000 down from the middle Lancet number still puts you in their 95% confidence interval; bumping 120,000 down from the bottom of that interval still gives you an unfortunate number of deaths.

  4. #4 wacki
    October 19, 2006

    Bumping 120,000 down from the middle Lancet number still puts you in their 95% confidence interval; bumping 120,000 down from the bottom of that interval still gives you an unfortunate number of deaths.

    It’s 120,000 per year. And according to this study:

    http://www.thelancet.com/webfiles/images/journals/lancet/s0140673606694919.pdf

    that’s 3 years worth. That’s 363,000 artificial deaths. Subtracting that from 654,000 puts you below the 95% confidence interval. Still, 290,000 dead is still a ton. Even if 70% of those are iraqi on iraqi then the US troops cause 100K deaths.

    If their survey underestimated the pre-war death rate due to some sort of systematic error, then the post-war death rate would have a good chance of being similarly underestimated.

    Possible, but I’m not sure it’s plausible The US forces weren’t around then. There is widespread forgery of identity documents. And since the US gov typically compensates the victims of violence there is financial incentive to exaggerate claims as well, and to have “proof” of those claims.
    [Link](http://www.nytimes.com/2006/06/10/world/middleeast/10payments.html?ei=5088&en=14e9181d3f0ff195&ex=1307592000&partner=rssnyt&emc=rss&pagewanted=print)

  5. #5 Chris
    October 19, 2006

    Oh, good; we have a control measurement. Thanks, wacki – that’s actually helpful. All we have to do is look up the statistics for US compensation for victims of violence, and we’ll have a minimum estimate for civilian deaths. Anyone know where I’d go to look that one up?

    ?

    [sound of crickets chirping]

    Oh, that’s right, the US never releases any figures on Iraqi deaths.

    “”There’s a transparency problem,” CIVIC’s Holewinski said of the Pentagon’s claims. In January, the group filed a Freedom of Information Act Request demanding access to records of families given condolences payments by the U.S. military.

    CIVIC’s founder Marla Ruzicka was killed by a suicide bomb in Baghdad while advocating for victims of war in Iraq. The group has long demanded that civilians killed or injured in conflict be counted and their families compensated by the governments involved.

    The group successfully fought for congressional legislation requiring the U.S. government to compensate civilians killed by the U.S. military. So-called condolences payments have been handed out since September 2003, but the military has never disclosed how many Iraqis have received money under the plan or under what circumstances the money was doled out.”

    Which would suggest very very strongly that they don’t think the files would support their argument. If US figures differed materially (by an order of magnitude, say) from the Burnham study, they’d release them. They don’t, so they don’t. End of story.

  6. #6 wacki
    October 19, 2006

    If US figures differed materially (by an order of magnitude, say) from the Burnham study, they’d release them. They don’t, so they don’t. End of story.

    I don’t buy this argument. Even if it’s only 60K dead I don’t think the US would release the info. The military learned some hard lessons during the vietnam war when it came to death statistics. It’s much better to simply not talk about it. Then again they did release the 30K statistic so maybe I’m wrong. As a scientist I refuse to predict what anyone’s personality might lead them to do.

  7. #7 Harald Korneliussen
    October 20, 2006

    wacki: “If the lancet study was off on prewar rates that can dramatically affect the “extra death” count.”

    Yes, but being off by the amount you suggest would be very suprising. It has been shown many times here that the pre-war mortality rate as reported is reasonable (for a contry with a young population, not effected by wars or genocide in the time frame in question, and protected from the worst consequences of the boycott through the food-for-oil program).

    I don’t know where you get your higher estimates for pre-war mortality from. But even if they were true, I suspect there would be just as much uproar on both sides if Lancet 2 “only” reported 400000 excess dead.

  8. #8 Sceptic
    October 20, 2006

    [I don't know where you get your higher estimates for pre-war mortality from.]

    Here are some, informally:
    http://channel4newswatch.blogspot.com/
    WHO ~ 9/1000
    UNICEF ~ 13/1000

  9. #9 JB
    October 21, 2006

    Wacki said: “I don’t understand how this article matches the title. If the lancet study was off on prewar rates that can dramatically affect the “extra death” count.”

    Supposing that the pre-war death rate was 9.7 deaths / 1000 per year (many people ignore the per year part, either becasue they are too lazy to educate themselves or they are simply dishionest) and that the Lancet post invasion estimate of 13.3 per 1000 per year is correct.

    That would make the total excess deaths 300,000 rather than the Lancet’s value of 650,000.

    This may be a significant difference but 300,000 is still no small potatoes.

    One needs to keep some perspective here. We are talking about human lives and hundreds of thousands of them. If this were happening in America, Europe, Australia or most of the “white” countries, there would be outrage — and rightly so.

  10. #10 z
    October 21, 2006

    “And since the US gov typically compensates the victims of violence there is financial incentive to exaggerate claims as well, and to have “proof” of those claims.”

    Eerie chills run up my spine; I was just arguing with some Usenet crank who asserts that the Holocaust was way overblown by Jews to try and get reparations from Germany.

  11. #11 Ragout
    October 22, 2006

    Note the reservations of Beth Osborne Daponte. She was critical of the first Lancet study as well, and is *extremely* credible. She was actually fired from her government job in 1991, after estimating a figure for Iraqi deaths from the Gulf War that the administration found inconvenient.

  12. #12 Robert
    October 22, 2006

    Ragout wrote:

    is extremely credible.

    Beth’s not trained either as a statistician or a survey specialist.

  13. #13 Ragout
    October 22, 2006

    Daponte may not be a statistician, but she seems to have had tons of survey experience. The government job I mentioned was at the US Census Bureau, and her CV lists stuff like conducting surveys in Soweto, and teach a class on “Data Collection Techniques for Human Rights Workers.”

    Anyway, I meant that she’s extremely credible because she’s actually counted the war dead in Iraq, and seems likely to have opposed the war.

  14. #14 Robert
    October 22, 2006

    I know Beth, and have since before the Census Bureau issue. She’s not a survey statistician.