Thursday, July 29, 2010

Head, Meet Wall

Well, Brad Wall, that is:
Saskatchewan Premier Brad Wall bolstered his support for a controversial multiple sclerosis treatment on Monday, predicting clinical trials could launch in the province as early as next year.

“I do believe there will be a solid proposal before the end of the year,” he said, urging other provinces to collaborate. “I think there’s a chance we’ll see potential trials in the new year.”

On Tuesday, Mr. Wall broke ranks with his provincial counterparts, vowing his government would finance liberation therapy, an experimental method of opening veins in the neck and spinal cord to combat the symptoms of the nerve-wasting disease.
While I do find it unseemly that politicians like Premier Wall have seen fit to intervene/interfere in research programs, the "head smashing" element comes more from the way the so-called liberation treatment has been treated in the media.

First, the very term "liberation treatment" itself sounds more like the work of a scam artist or at least a PR hack. Second, many articles or stories on the controversy seem to construct a narrative of desperate, hopeful MS patients set against skeptical neurologists (possibly in collusion with "Big Pharma") and governments. Certainly, most internet commentators seem to follow that pattern, arguing that the treatment (a sort of venous angioplasty) is common place (it isn't), perfectly safe (nope), and warranted even in the absence of symptoms or evidence of any connection to a disease process (definitely not). There is more than a little bit of lay person ignorance on display - conflation of arteries and veins, ignorance of anatomy and hemodynamics, and a lack of understanding of physiology. The general attitude that, since the procedure provides hope, and anecdotal reports have been favourable, we needn't bother with properly conducted clinical trials or research and simply began booking expensive imaging studies and scarce time in the cath lab for patients who may neither need nor benefit from the treatment. I think Colby Cosh at Maclean's has said it better, though:
How could anyone be so pessimistic? Well, even leaving aside the history of MS quackery and hype, there is no shortage of circumstantial reasons. The “liberation therapy” tag is an obvious mark of heavy con-artist and/or halfwit involvement in the publicity effort. Why not go all the way and just call the Zamboni technique “super amazing unicorn magic”? In newspaper accounts (and even in our own exemplary coverage), recipients of the therapy often report renewed energy without necessarily enjoying total relief from symptoms; this may not be a sign of the placebo effect at work, but it is certainly consistent with it. And it is hard to understand how the instantaneous improvements so often described by the “liberated” can possibly be consistent with Zamboni’s actual theory of MS etiology—i.e., that poor drainage of blood from the brain encourages, over a long term, the formation of cerebral iron deposits that then lead to immunological issues and demyelination of the nerves.
He's completely right on the last point, of course - even if the "liberation" treatment worked, the effects would not and could not be seen immediately, let alone within seconds or minutes of angioplasty (as seemed to occur with a woman interviewed on the National last night, who reported instant resolution of numbness in one finger). Hope is a great thing, and the placebo effect is non-trivial in these cases - to say nothing of the impact of individual psychology. However, as one of my colleagues has said in the past, "Hope is not a plan." Brad Wall should stick to politics, but should surely resist political pressure to interfere in things he shouldn't.

Wednesday, July 21, 2010

Reminding the Globe come election time...

The Globe and Mail writes in an editorial:
Good government is about leadership – focusing the population on the important challenges of the future, not distracting them with sideshows – and management: inspiring an organization to do the best work of which it is capable.
This was in reference to the news that the chief statistician has resigned due to the government's decision to eliminate the mandatory long-form census.

Now, in each of the past two federal elections the Globe has endorsed the Harper Conservatives when it came down to the wire. Yet I cannot think of a single time when they have shown the kind of leadership that this newspaper describes in the quotation above. I would hope that they remember this when writing their electoral endorsement prior to the next vote. The Liberals may be listing without a rudder, but I'd sooner have bland competence over the kind of authoritarian "vision" on display in the Harper government.

Saturday, July 17, 2010

Further to that whole census thing...

If Jeffrey Simpson is to be believed, I should have given Tony Clement a little less grief the other day:
Last fall, Prime Minister Stephen Harper decided his government would oppose the mandatory long-form census. Since then, nothing has changed his mind. His right-wing ideology and political instinct combined to make a policy that’s being denounced by almost every leading institution and commentator in Canada.

His decision was also opposed inside the government by Finance Minister Jim Flaherty and by Industry Minister Tony Clement, who’s responsible for Statistics Canada, the agency that administers the census.

Both wrote to the Prime Minister, underscoring the importance of the mandatory long-form census to compile the most accurate statistics on which so much public policy and private-sector decision-making depends. The issue went back and forth inside the government, but, as with everything in Mr. Harper’s Ottawa, the Prime Minister decides.

His is a government in which most ministers are reduced to silence, except for those kept on short leashes, and in which everything, down to astonishingly small details, are decided by the Prime Minister, and only by him. His mind can be changed, but only occasionally and usually only after the passage of time between his initial decision and a new one. In this instance, despite internal discussion, his initial decision has stuck.
So, as ever, I can assign the blame to Harper himself. Yet it seems plain to me that a cabinet minister in this position ought to have the courage of his convictions and resign. Flaherty too. Would that damage the Harper government? Absolutely - and so it should. Where are the conservatives who favour good policy over this asinine autocratic nonsense? Is it just about ideology?
Clement’s statistical illiteracy is so profound it gives one vertigo. The notion that simply making the sample bigger can’t fix a skewed sample is something undergraduates learn in first-year classes, yet is somehow beyond the mental grasp of a senior minister of a G8 country. And the comedic benefit of watching Clement fail first-year economics is undermined by the cold realization that he fundamentally does not understand the intellectual foundations of the files that he controls. When he is cornered by his intellectual betters, moreover, Clement’s instinct is to reach for the debating-hall comforts of cheap populism.


There are libertarians and there are libertarians. When it comes to Tony Clement and James Moore, theirs is not the principled and defensible small-government ideology of Friedrich Hayek and Milton Friedman. It’s more like the sweaty-palmed fanboy libertarianism forged by too many late nights in high school spent switching between the anti-feminist Nietszcheanism of Ayn Rand and the corporatist space fantasies of sci-fi writer Robert Heinlein.
I consider it a gross failure of the uttermost negligence by the press and - ahem - the Official Opposition that this cabal of morons remains ensconced in power.

Thursday, July 15, 2010

A few changes for health care

  • Eliminate pagers (replacement value: $375) in favour of secure hospital-issued mobile phones.
  • Move to electronic medical records integrating primary and hospital/specialist-based care. Family physicians don't need to be sent entire inpatient charts, but they need to have access to them when relevant. The reverse goes for hospital-based physicians and other health care workers.
  • How about handheld devices instead of print-outs of patient lists? What is not lacking is the technology so much as the integration of technology.
  • More long-term care beds and rehab facilities (community and hospital-based). Far too many patients waiting for ALC or rehab languish in acute care wards that do not provide an ideal environment for them. And it's wasteful.
  • Centralize referrals/wait lists to expedite investigations and follow-up. Triage these to determine who is waiting and why.
These's more, of course, but these are just random thoughts that've come up on my elective in the past few weeks. It's probably a good idea to hire more nurses too.

About that long form census...

It goes without saying that the Harper government's decision to eliminate the mandatory long-form census, replacing it with a voluntary survey, is beyond stupid. They claim that the mandatory survey is "coercive" and an invasion of privacy. Or something:
In a written statement Tuesday, Clement said the short-form census, which is still mandatory, will provide a sufficient demographic picture of the country.

"The government does not think it is necessary for Canadians to provide Statistics Canada with the number of bedrooms in their home, or what time of day they leave for work or how long it takes them to get there," Clement said. "The government does not believe it is appropriate to force Canadians to divulge detailed personal information under threat of prosecution."

Garneau argued Clement does not understand how scientific data is gathered or used, and that the census has to be mandatory to get responses from a wide variety of people. He said that information from the long-form census is essential for the development of sound government policies.
I'll leave aside the fundamental reasons why this is a stupid idea and address Clement's comments directly. First, it's worth noting that nothing in the census data will, in the end, reflect any individual information. Second, Clement's own examples seem rather important to me - commuting time, for example, is a rather good proxy for the likes of traffic congestion and patterns of daily movement. The question of where people work vs. where they live, and how far they must travel daily, is of pretty obvious relevance to urban planning, highway construction, public transit, and a host of social policy issues. I'm not sure what about such questions is overly "personal" either.

So what's the real problem? Well, while it's nice to think that a voluntary survey would achieve a sufficiently high response rate, this strikes me as doubtful. Currently the mandatory survey is sent to 20% of Canadian households (I presume these households are chosen randomly). The line from the government seems to be that a voluntary survey might reach a larger number of Canadians, and that this would be superior to the mandatory survey of 20%. This is, however, wrong. Any kind of survey of a population contains some element of sampling error. You can actually predict the size of this error by choosing an appropriate sample size. Now, 20% of Canadian households is a big sample. REALLY big. The sampling error implied by such a large sample is very small, so small in fact that increasing its size to 25% or even 50% of households will not make a significant difference. Happily, because this survey is mandatory, there is minimal non-response and so the results of the sampling are said to be "unbiased".

Unfortunately, a voluntary survey leads to an unpredictable degree of non-response bias in the results. Bias is a form of structural error in a statistic that cannot be eliminated by increasing the sample size (which is not important in this case anyhow). We can imagine that poor people (or wealthy ones) or anarchists or libertarians or contrarians or any other sort of socioeconomic or political group might be more or less likely to respond to a voluntary survey. That's bias. And it means that the results of the survey may not - and almost certainly will not - be representative or generalizable to the Canadian population. That's a demonstrably inferior survey sample - less reliable, less accurate, and in ways that are difficult to quantify. We can estimate sampling error fairly readily, but that does not hold for sampling bias, since it requires a great deal of information about the sources of bias. Of course, without the mandatory long-form survey, it seems unlikely we'd know why particular people failed to respond to a voluntary survey. Quite the catch 22.

So, Tony Clement, with respect to this:
“I am not saying it's every Canadian, but I am saying there are Canadians [who complained] and we should try to accommodate their concerns in a balanced way,” he said.

He added that he took the privacy concerns to Statistics Canada and asked they be incorporated into the next census. “They gave me options and we chose one of those options,” he said.

“This is a methodology that Statistics Canada offered to us and if it's good enough for Statistics Canada, it should be good enough for some of our critics.”
As I happen to know a number of statisticians, I'm rather skeptical that Statcan thinks this change is "good enough". At this point, I should note that indeed have some kind of degree: MMath (Statistics-Biostatistics) from Waterloo. I think that beats Tony's poli sci undergrad (I have one too) and law degree - at least insofar as these things go.