What's the difference between national polls and scientific data?
As this article at Pollster.com points out, the difference is transparency. The article takes the example of climate change modeling as one instance where a set of people with a big heap of quantitative data and statistical models share the data and the models' assumptions.
Interestingly, it's only since one month ago that clinical trials were required by the FDA to make some basic data accessible--September 27 of this year. But actually, it seems like this does not give the opportunity to re-examine the raw data--only a kind of summary of demographics and outcomes. The intent is to stop people from concealing negative trials.
But, to take the pollster.com point in another direction, shouldn't drug trials be more transparent than political polls, which are run for profit by people who have a financial interest in concealing their raw data and their weighting methods (e.g., for "likely voter" screens)?
Oh, right. So are drug trials. Sorry.
But the ultimate transparency, and one that seems like it's long overdue, is for raw clinical trial data to be open-source, so that people with interests other than profit can examine that data and re-analyze it after the original academicians have published the initial report.
Sunday, October 26, 2008
What's the difference between national polls and scientific data?
Thursday, October 23, 2008
This journal abstract caught my eye while searching for something else having to do with economics and HIV risk:
Women and Fish-for-Sex: Transactional Sex, HIV/AIDS and Gender in African Fisheries
Christophe Bénéa and Sonja Mertenb
WorldFish Center, Africa Regional Office, Cairo, Egypt; University of Basel, Switzerland
Accepted 22 May 2007. Available online 10 March 2008.
This paper analyzes the phenomenon of fish-for-sex in small-scale fisheries and discusses its apparent links to HIV/AIDS and transactional sex practices. The research reveals that fish-for-sex is not an anecdotal phenomenon but a practice increasingly reported in many different developing countries, with the largest number of cases observed in Sub-Saharan African inland fisheries. An overview of the main narratives that attempt to explain the occurrence of FFS practices is presented, along with other discourses and preconceptions, and their limits discussed. The analysis outlines the many different and complex dimensions of fish-for-sex transactions. The paper concludes with a set of recommendations.
Key words: artisanal fisheries; vulnerability; poverty; public health; Africa
It's actually a pretty thoughtful article and among other things makes sure we don't oversimplify the fish-for-sex phenomenon which I have to say I was immediately tempted to do. For instance, one thing that I didn't think about right off the bat was that "[W]omen fish traders—whatever way they ‘purchase’ the fish, i.e., with cash or through sexual arrangement—are economically productive agents within the fisheries sector... [and are] fully integrated in the fish value-chain" which despite the absurdity of that last phrase, appears to actually be a fair point (see below).
"Women engaging in FFS transactions are often depicted as sex-workers by their own community/society, conveying more or less explicitly a link between FFS and prostitution. While prostitution undeniably exists in the sector and fishers are certainly one of the socio-professional groups which have the most frequent contacts with sex-workers, assimilating FFS to sex-workers is socially and economically questionable. In particular, it does not acknowledge the fact that women fish traders—whatever way they ‘purchase’ the fish, i.e., with cash or through sexual arrangement—are economically productive agents within the fisheries sector: like any other fish traders, they process, transport, and retail fish. They are thus fully integrated in the fish value-chain, in contrast to sex-workers who do not create direct value-added in the sector.
"The association FFS-prostitution is also recurrently brought forward as part of the narrative of the poor, destitute woman who is forced to prostitute herself to buy fish—cf. Table 4. Although it can hardly be denied that female fish traders can be remarkably vulnerable to poverty—in particular the widows, single mothers, or divorced women—assuming a systematic link between extreme poverty and transactional sex may be too simplistic to capture the complexity of the factors leading women to engage in FFS. In particular it does not reflect the fact that women are socially active agents who may rationally choose their behaviors and negotiate the nature and continuance of their relationships with their partners. What, instead, the quotations listed in Table 4 may illustrate is that a large part of the literature essentially from NGOs and advocacy groups that focus on addressing extreme destitution and poverty among vulnerable groups (and in particular women) tend to use extensively or to instrumentalize the narrative of 'the poor woman who is forced to prostitute herself to survive' in order to draw public attention to their own cause."
"The existing documents reporting FFS indicate that a large proportion of the women who engage in FFS are widows, divorced or single women, re-emphasizing the relatively high vulnerability of this group to poverty and thereby reflecting the safety-net role that fish trading activities traditionally play for a large number of poor women, especially in Africa. This link between FFS and female fish traders’ vulnerability has been captured and reflected in a certain number of narratives and discourses which attempt to explain the occurrence of these practices. The most frequent one is probably the miserabilism narrative where FFS is viewed as a 'strategy for survival' and women engaging in FFS as victims. Linked to this perception and reinforcing it is the very frequent confusion made between FFS and prostitution. While this article demonstrates why this confusion is disputable, it also recognizes that the increasing vulnerability of female traders is a reality which certainly reduces the negotiation/transaction power of these women, and also encourages fishers to impose these FFS transactions through 'no-deal no-fish' coercive arrangements. At the same time, the new institutional economic approach proposes an alternative to the miserabilism narrative and highlights the transactional dimension of FFS practices, suggesting that the lack of cash may not systematically be the only determinant that leads women to engage in FFS. Surely, there is no contradiction between these two interpretations. Social structures or institutions, class, gender inequality, kinship, and marriage do have a bearing on women’s decisions, but those must still be seen as social actors with some power to negotiate."
Kyle makes a couple of arguments below in the comments of my last post, and my reply is long enough and separate enough from my original post that I'm posting it separately:
I don't disagree with your political conclusion of what to do at the end of the day. The point is that any president might die. The fallacies of the Altman argument are that:
1) the medical chart does not contain information on what is most likely to kill a president; and
2) John McCain has some unknown risk of recurrent melanoma, which further information might allow us to calculate slightly differently than what we know to be his generic risk without further information. But John McCain either will or will not die in office if elected. And, with or without melanoma, he has a reasonable probability of dying in office because US presidents generically do have a much higher probability of dying in a given four year span than many other people, entirely because of the risks associated with the office rather than the officeholder.
So whether the possibility is x% chance of melanoma combined with y% chance of cardiac disease combined with z% chance of lung cancer, the generic risk to the officeholder already meets a test of likelihood. That is, statistically, taking any president at any age, a generic voter should assume--regardless of what is in the medical chart--that the president is at least as likely to die before the end of the term as the voter herself, or at least, the voter's children.
So, the reason this is relevant to a medical blog and a medical argument is that melanoma in particular should not change the intervention--i.e., your vote. Whether or not he has a given chance of recurrent melanoma, Sarah Palin is not a qualified vice president, and she has a high generic chance of becoming president if elected as vice president.
Incidentally, though the two candidates' generic risks of mortality can be influenced by their age, this is an easily discernible and intuitively obvious risk which does not require Lawrence Altman digging through colonoscopy reports.
Because the baseline presidential risk of death is high, the issue of Sarah Palin's competence is more or less exactly the same as the issue of Joe Biden's competence. If Obama had picked Palin, it would be just as bad a pick, for the exact same reason.
Now, take the low-probability but possible chance of Lawrence Altman finding something in the chart that a group of Mayo Clinic doctors deliberately concealed or misrepresented when they vouched for McCain's health. When going through McCain's chart, the greatest likelihood is that whatever Altman would find would be a "false-positive"--that is, it would raise concerns for voters but would not actually change the outcome of the next four years.
That would be unfair to McCain, and more importantly to democracy in general. It would represent a medicalization of democracy--a completely out-of-proportion ability of a few doctors and medical screening tests to influence democratic elections.
Also, at least as importantly, it would be unfair to anyone with "concerning" things in their medical charts who wanted to be in a powerful position. There is no magic about a president; to the workers of a company, the CEO and CFO might well have greater power to determine their quality of life in the next four years. So, should boards of directors have the right to examine every bit of the medical record of any executive? And how far down the management trail are you willing to go with that logic? And what does that mean for people with family history of genetic diseases, for people with past medical issues, for people with high epidemiological risk?
Aside from this, I want to make sure I am clear about the statistical and medical argument I'm making, so let me take a less-loaded and very common medical parallel. Let's say someone comes into the emergency department with shortness of breath and a fast heart rate. There are various possibilities. One is a blood clot in the lung, known as a pulmonary embolism (PE).
To diagnose PE, I can get a CT scan with contrast, which can damage the kidneys. I can also do a blood test, the result of which will increase or decrease my estimate of the chance that the person has a PE. If the blood test increases my estimate, I'll get a CT scan. If it decreases my estimate, I won't get a CT scan.
So, if I think there is a clear alternative explanation and no reason to suspect PE, should I get the blood test? No, because it will not change my decisionmaking. I am more likely to get a false positive than a true positive, and therefore, the CT scan is more likely to be dangerous than helpful.
What if it's someone has a very high risk of pulmonary embolism--a known clot in the veins of the leg, and cancer which predisposes to PE? Will I do the blood test? No, because I don't care if the test is negative. I will still not be satisfied until I do the CT scan.
So it turns out that the only time to do the blood test is if you're not sure whether or not a PE is likely--the risk is indeterminate, or "medium-risk." The argument Altman is making relies on the idea that a medical chart is the equivalent of this blood test. That is, you will cast your vote--the potentially wise or unwise and highly consequential decision, the equivalent of CT scan with contrast--based on the information in the medical chart. This is a common issue in medicine: will a given test change your medical choices? If not, why are you doing the test?
Given that the Altman chart review is the equivalent of the "medium-risk" blood test, where we are trying to convince ourselves that a candidate will very likely die in office or will very likely not die in office. But this is not the right choice from the point of view of the "change your choice" test. That's because a president is not medium risk for death in the next four years. At least historically, a president is high risk. So, I certainly will not fail to care about the qualifications of a vice president. But I will not use the medical chart to decide how much I care. I already care a lot, because I know no matter what the chart says, I care. Any reasonable person should vote with the assumption that a president has a high chance of dying in office.
If examining the chart had no impact, then it wouldn't matter. And I'm the last person to defend McCain.
But I'm not defending McCain or a decision to vote for him. I'm defending people with a history of melanoma, and a lot of other people too. For anyone with higher probabilities of disease (whether through genetics, behavior, or past medical history), the risk of making the argument Altman is making is actually quite high. So, thinking through the issue of whether you do a test, and whether the Altman chart review is a test we should be doing:
the test does not change my ultimate decision
the test has a high chance of falsely influencing my thinking
the test has a high chance of other bad effects.
And therefore, the test should not be conducted. And Lawrence Altman doesn't need to look through every page of John McCain's medical chart.
[edited for clarity later in the day]
I vote against John McCain because he is a risk to people with melanoma, not because of his risk of melanoma.
Before I go any farther, let me just say that this post is the one time I'll say anything sympathetic about John McCain who I desperately hope loses this election and loses big. But this isn't about him, really.
It seems like during most election seasons, the New York Times' Lawrence Altman MD seems to get worked up about whether he has had enough access to political candidates' health records. Altman was a medical resident about 40 years ago and has never been much of a clinician as far as I can tell besides that--he did preventive health, public health work, and journalism. But, he seems to feel that reporters--and especially, he, being a doctor/reporter--have a right to go over presidential candidates' health records.
This is an appalling idea if we take away John McCain and our hope to see him lose, and think about this in the abstract. And I'm frustrated that a bunch of doctors who support Obama have apparently signed some kind of letter asking that McCain release all his medical records, and that some of them are saying a bunch of stuff in public about his melanoma risk. First of all, I don't know anything more about John McCain's melanoma risk than Bill Frist knew about Terri Schiavo's neurological function, which is to say, I know better than to pronounce my opinion about it.
Second of all, if I was able to look at all of John McCain's medical records, do a physical exam and history, and then quickly become a melanoma expert, does risk for a serious health condition mean that you're supposed to bow out of public life? If you think so, how far down does this argument apply? Governor? Mayor? City Council? Why would it stop at any particular level of office? If the argument is reasonable at the top, why shouldn't the voters of any given town know whether their mayor had guaiac-positive stool? Is it relevant to know whether your congressional candidate might have a brain aneurysm? Is it your right--no, your duty as a citizen--to demand full body CT scans and head MRIs for every person entering any political race at all? As a doctor, shouldn't I reserve my vote only for the candidate who puts his colonoscopy report up on the web so I can look inside his ass and judge for myself whether his polyps are sufficiently presidential?
John McCain's health plans mean his risk to people with melanoma is much more significant than his own risk of melanoma.
Finally, epidemiologically, the melanoma argument opens the door to a truly terrible line of logic, because underneath the medical argument must always be an epidemiological argument. By far the most common cause of death among US presidents in office is assassination. And deaths from cholera or bacterial pneumonia are unlikely for current US presidents. For all of Lawrence Altman's piety about presidents concealing their medical conditions, JFK hiding his Addison's disease was obviously irrelevant in the larger scheme of things. If we're so concerned about a president's chances of death, should we ask Lawrence Altman to be joined by security experts who can analyze the candidates' risk for being assassinated before we vote, which in presidential epidemiology is more likely than death from cancer? Does the public have a right to read all the death threats sent to presidential candidates so we can judge for ourselves whether they are serious? Shouldn't the Secret Service be granting the public complete access to suspected or potential assassins-in-the-making to assess whether they are serious threats or just rifle-toting equivalents of negative lymph nodes? In this election, I don't even want to think about such a thing.
So presidential epidemiology be damned; I am casting my vote for a black man with a significant smoking history and a bunch of racists who want him dead. I'm voting for him because of who he is while he is alive, not because of my morbid guesses about when he might die.
(If you want to be a doctor for Obama, here's a more reasonable way to do it.)
Monday, October 20, 2008
This weekend, we saw a great movie.
It's been a while since Ms Dr Hemodynamics and I have had an actual date, what with lots of night float shifts, lots of moving and fire logistics, and lots of just plain being overwhelmed by events. But Friday night we had a great date. When we met in medical school one of the first conversations we had was after I said I'd just seen The Station Agent and how I thought it felt--in its smallness, its authenticity, and most of all its particularness, the way it was a story just about these people and no one else--like You Can Count On Me. She said, "I loved that movie!" and that started one of those early conversations where we realized we had some tastes and ways of looking at the world that might match up. Another one of those conversations took place at the B-Side Lounge, a restaurant not far from a movie theater we like, where we went for our first date.
So last night, as if to restart our dating life after all the chaos in our lives, we went to the movies and then the B-Side. The movie was Rachel Getting Married, written by Jenny Lumet (Sidney Lumet's daughter) and directed by Jonathan Demme. The writing is smart, with natural-sounding dialogue supporting a tightly-structured story. The casting is so rich and the acting so good that even minor characters seem like interesting people, believable people. And like The Station Agent and You Can Count On Me, these characters don't belong anywhere else except in this story, this movie, and for that reason, they fill the movie and seem to live beyond it. Demme keeps the hand-held cameras moving, but close-in; we are guests at this wedding, not omniscient viewers.
Anne Hathaway is the center of the movie as Kym, Rachel's addict sister, back from rehab on furlough to see her sister get married. She starts the movie as a completely irritating and totally self-centered person who seems mostly frustrated that her sister's wedding is not really about her. Kym never turns into an angel, but the depth of her character and the complexity of her relationship to her family slowly evolves beyond addiction's irritating interpersonal effects and into its more profound pain and tragedies. I ended up feeling strongly connected to her even as her tally of bad deeds and pain caused becomes larger and more awful as the movie goes on. The movie seems as if it is about her, and thus about a family's relationship to an addict--and it is. But we come to realize the movie is also about something and someone else: a family's relationship to a person who isn't present at all, except in all the main characters' thoughts.
The movie revolves around Kym, and that means it's not a big sprawling multi-character document of a family; it's a much smaller movie than that. Nonetheless, it becomes an ensemble movie because the actors playing the other characters are compelling and interesting enough that you begin to get a sense of them as people just by watching them watch Kym. Bill Irwin, Anna Deavere Smith, and Tunde Adebimpe are all people with their own creative agendas, and their intelligence and watchfulness is part of what makes each of them so compelling as actors.
I'd love to know Kym and Rachel's dad, played by Irwin--he's a sweet, generous-spirited guy--but he'd clearly do well to get himself to a Nar-Anon meeting before he offers someone another sandwich. Irwin, a guy who has taken clowning to a new level of art, and plays Elmo's friend Mr. Noodle on Sesame Street, uses his big mobile face to underline the desperation of his hope that happiness can reign. His expressiveness and hope is contrasted with the cool distance of Debra Winger as Kym and Rachel's mother, who makes a late appearance in the wedding proceedings and in the movie, but makes every second count.
Tunde Adebimpe, of the band TV On The Radio, plays the groom, Sidney. He is a large almost awkward-seeming man, but his gentle kindness amidst the emotional chaos make it clear why Rachel needs him, and why she is so delighted to be marrying him. Sidney and his friends and family stand in contrast to Rachel and Kym's tense prickly family web. They are constantly in the background of the movie as a vision of ease and happiness that Rachel is trying to grab for, and Kym thinks she'll never have.
Go see it.
Saturday, October 18, 2008
Gay marriage: it's not just for anonymous trailblazing ordinary people anymore--but even celebrities can get their rights taken away in November
If you make one political donation this season, the way to have the biggest long-term impact for your dollar is right here:
No On 8 Website
Yes, you should pony up for Obama--but lots of people are already doing that. Fewer people are donating to another important campaign, which means your donation can make an even bigger difference for the dollar. The campaign to save same sex marriage in California is an urgent moment for equality in the United States, and it will be a turning point for the struggle for equal rights for gays and lesbians. Recent polls show that the latest misleading ads for the proposition are working, and many Californians are prepared to vote for Proposition 8. If the election was held today, Prop 8 would win. That would be terrible news for my friends and family in California who need same-sex marriage for all kinds of practical reasons, and also some basic reasons of justice and equality.
I hope you'll join me in opposing Proposition 8. We in Massachusetts can breathe easy knowing that same sex marriage is safe here for now--but if it's defeated in California, the forces of intolerance will be coming back here to try to roll back the clock. I don't make a lot of money as a medical resident, but I just gave $200.00 to this campaign. I hope Hemodynamics readers will consider joining me--and if you do, let me know in the comments section of this post.
(PS: A challenge grant means that if you donate before Sunday October 19, your donation will be matched dollar for dollar--so you can double your already significant impact.)
Saturday, October 11, 2008
It's too long a story to tell here for now, and with too many complicated feelings to tell easily. But, we had a fire in our apartment building, and we were temporarily homeless (though in an upper-middle-class stay-at-your-friends' houses kind of way), and now temporarily housed. I feared for my life only in retrospect, and all of the Hemodynamics family got out safely.
We're actually back in our old building but in another part of it, subletting the apartment of someone who didn't want to come back while the building was being rebuilt. In our old apartment most of the walls and ceilings are now demolished: our apartment itself didn't burn, but the water of the hoses came down through the walls to our apartment from where the fire was being fought above.
The halls are full of the white plaster dust, and the floors in the halls are stripped down to the wood underneath them. Everything is dusty and each time I turn the corner I smell the smell of smoke, which just reminds me of that night. Coming back to our building means smelling smoke, both literally and figuratively. It means being reminded of a traumatic event. But it also means reclaiming that event not simply as a disruptive moment, but as something that is part of our history, and shapes our future. It smooths out the trauma, into the clay of the larger lives we build. I think it's a good thing.
In the hospital, I realized recently that I was in a "don't f- with me" mood. Without my clippers and feeling grumpy about buying new razors and other such things that the movers were supposed to return to us, but didn't, I let my beard grow into a unruly patchy mess. Facial-hair-wise it was if I was some kind of Che Guevara wannabe slouching through a Harvard hospital, just biding my time until I could really make some trouble. I was using swear words more than usual. I was making dark jokes more than usual.
Today, maybe it's a sign of starting to recover that I went to the barbershop, and got my beard trimmed, and my hair cut, and even got shaved above and below my beard line with a straight razor, an unprecedented event. Slowly, I think my unconscious mind is joining my conscious mind in rejoining the normal world.
Still, out in the hallway it smells like smoke. It's going to take a long time for that smell to go away.