Saturday, December 4, 2010

Yes, This Again.

The impetus behind this blog was a study that written about in the NYT about an AIDS vaccine. The study was completely inconclusive, yet was promoted as a major advance. Here we go again:
In the study, 2,499 men in six countries — Brazil, Ecuador, Peru, South Africa, Thailand and the United States — were randomly assigned to take either Truvada or a placebo and were followed for up to three years. For ethical reasons, they were also given condoms, treatment for venereal diseases and advice on safe sex. There were 64 infections in the placebo group and 36 in the group that took Truvada, a 44 percent risk reduction.
Two in the Truvada group turned out to have been infected before the study began. When the remaining 34 were tested, only 3 had any drug in their blood — suggesting that the other 31 had not taken their pills.
Different regimens, like taking the pills not daily but only when sex is anticipated, also need testing.
Also, many men in the study failed to take all of their pills, and some clearly lied about it. For example, some who claimed to take them 50 percent or 90 percent of the time had little or no drug in their bloodstreams.
The pills caused no major side effects, though men who began to show signs of liver problems were taken off them quickly. Some men stopped taking the pills because they disliked relatively minor side effects like nausea and headaches. Also, some stopped bothering once they suspected that they might be taking a placebo.
“People have their own reasons,” [Policy Director of amfAR Chris] Collins said. “People don’t take their Lipitor every day either.” 
Again, how hard is it to take sqrt(1250)? But then there's the feckless methodology! Truvada is also apparently effective regardless of the regimen. Imagine that. So is prayer.

I was wondering what is going on with these AIDS studies that keep showing comparably inconclusive results, yet promoting them as breakthroughs. So I went back and looked at the previous study. Then I found this released a month later calling into question that study. And then I realized: all three of these articles were written by the same author, Donald McNeil, and both studies were under funded via the National Institutes of Health infectious diseases director Dr. Anthony Fauci. But this was especially rich:
Putting several biostatistical analyses in a news release “would have confused everybody,” Dr. Fauci said, and suggesting that the researchers were engaging in a cover-up is “absurd.”
Everybody? Statistical analyses are not confusing if they are conclusive; if only one method out of several confirms your hypothesis, your data is not conclusive.

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