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AIDS Vaccine Is Partially Successful
ifchairscouldtalk writes "A Phase III 'RV 144' study in Thailand succeeded in reducing HIV infection rate in trial with 31.2% effectiveness. The study was conducted by the Thailand Ministry of Public Health and used strains of HIV common in Thailand. It is not clear whether the vaccine, which combines AIDSVAX with Aventis Pasteur ALVAC-HIV canarypox vector, known as 'vCP1521,' would work against other strains in the United States, Africa or elsewhere. Strangely, the vaccine had no effect on levels of HIV in the blood of those who did become infected, providing 'one of the most important and intriguing findings' of the trial, according to Dr Fauci, director of the National Institute of Allergy and Infectious Diseases, which is one of the trial's sponsors."
I'm not normally a stickler for these, but AIDS is a syndrome, HIV is the virus that causes it. The vaccine can prevent you from acquiring HIV and thence from developing AIDS. It's not a cure, it's a preventative measure.
I was promised flying cars...Why are there no flying cars?
The sample sizes were not 74 and 51. The sample size of people vaccinated was "more than 16,000 volunteers". 74 and 51 were just the number of people infected, which is still statistically significant. [to what confidence level, I do not know].
someone do some analysis on the statistics and tell us all something and get +5
Sure. It's Poisson statistics, so the standard deviation is the square root of the count.
placebo: 74 plus or minus 8.6
vaccine: 51 plus or minus 7.1
The statistical significance of the difference (23) is equal to the standard deviation of the sum (not the difference!) of the counts, so:
difference between placebo and vaccine:
23 (=31%) plus or minus 11
= (2.06 standard deviations)
Assuming they set their criteria for statistical significance at two standard deviations, then they are significant.
http://www.geoffreylandis.com
Didn't the article say that one group got a vaccine, and the other got a placebo?
"Col. Jerome H. Kim, a physician who is manager of the armyâ(TM)s H.I.V. vaccine program, said half the 16,402 volunteers were given six doses of two vaccines in 2006 and half were given placebos."
Oh yea, that's what it said.
I don't see anything wrong with the basic kind of study. As I said, they may have fucked it up somehow, such as fucking up the selection of the participants and grouping them.
And why would they want to control against additional groups? They're measuring one thing. How effective is the vaccine. Your proposal to control against other groups are actually separate studies. They can and should be run independently at first. I can totally understand them not wanting to add complexity to a study that already has more than 16,000 participants.
So, I still don't see any valid objection as to why this kind of study won't work or is flawed somehow. In fact, this basic type of study is done all the time.
Fascism trolls keeping me up every night. When I starts a preachin', he HITS ME WITH HIS REICH!
The total working group for this test was around 16,000 people. Only 125 actually became infected with HIV during those 3 years. The infected portion shows about 1/3 more in the placebo group. So yes, the sample is statistically significant, and someone wasted a mod point.
Who is John Cabal?