HIV/AIDS Skepticism

Pointing to evidence that HIV is not the necessary and sufficient cause of AIDS

Posts Tagged ‘statistical significance’


Posted by Henry Bauer on 2009/09/24

“An experimental HIV vaccine has for the first time cut the risk of infection, researchers say. . . . The vaccine was a combination of two older vaccines that on their own had not cut infection rates. . . . The results found that the chances of catching HIV were 31.2% less for those who had taken the vaccine — with 74 people who did not get the vaccine infected and 51 of the vaccinated group infected. . . . ‘This result is tantalisingly encouraging. The numbers are small and the difference may have been due to chance, but this finding is the first positive news in the Aids vaccine field for a decade,’ said Dr Richard Horton, editor of the Lancet medical journal” [emphases added; “HIV vaccine ‘reduces infection’”].

“’Before this study, it was thought vaccine for HIV is not possible,’ Col. Jerome Kim, who is the HIV vaccines product manager for the U.S. Army, told CNN. Kim emphasized that the level of efficacy was modest, but given the failures of previous HIV vaccine trials, ‘yesterday we would have thought an HIV vaccine wasn’t possible.’ He called the results from the trial an important first step that will help researchers work toward a more effective vaccine. . . . ‘This shows a statistically significant effect,’ Kim said. . . . Researchers will announce details of their initial findings in October at the AIDS Vaccine Conference in Paris, France. The study was funded by the National Institutes of Allergy and Infectious Diseases and the U.S. Army Medical Research and Materiel Command. According to Kim, the U.S. military was involved in the study because U.S. service members are at risk and ‘there’s a national security threat from HIV’” [emphases added; “Combo vaccine reduces risk of HIV infection, researchers say”].
Rhetorical questions:

What makes “HIV” a “national security threat”?

Why did the news media broadcast something that has yet to be announced?

Why the difference between the BBC’s report that the results may be due to chance and CNN’s report that they are statistically significant?

Who calculated “31.2%”? If the actual numbers had been 50 and 74 instead of 51 and 74, it would have been 32.4; if 52 and 74, 29.7%. Or — as anyone who ever learned about “significant figures” in math should know, or as common sense might also indicate, you can’t start with numbers that have only two digits in them, like 54 and 74, and calculate to an accuracy of 3 digits. The only proper description of the difference would be “about 30%”.

Might we expect some at least speculative discussion about how two vaccines that had no effect could have an effect when combined?

Perhaps, if this is published after the conference, some of those questions might become answerable. In  the meantime, the purpose has been served:
Unwarranted public kudos for the researchers and a further entrenchment of the notion that “HIV” is a threat to everyone.

An HIV Skeptic, on the other hand, might look at it rather differently:
125 people among 16,000 became “HIV-positive” over a period of 3 (CNN) or 7 (BBC) years: about 8 per thousand, so 1.1 (BBC) or 2.7 (CNN) per thousand per year.
“HIV-positive” rates of a few per thousand are common in many “low-risk” groups.
It is known that DOZENS of conditions — for example vaccinations, various infectious diseases (other than “HIV”!), pregnancy — can bring on an “HIV-positive” result.
The difference between 51 and 74 could very easily result from differences between vaccinated and placebo groups in rates of pregnancy, flu, anti-tetanus shots, abuse of steroids, or any number of other circumstances.

Posted in clinical trials, experts, HIV risk groups, HIV/AIDS numbers, uncritical media, vaccines | Tagged: , , , | 34 Comments »