No evidence circumcision works = It may work?

It's natural to seize any possible hope for slowing or stopping the spread of HIV. Some researchers have spent careers investigating the hypothesis that less penis will lead to less HIV. But even when evidence emerges that this hypothesis is wrong, it is spun as hope that it may still be right.

Today it is reported that in the latest study of 4,889 homosexual men, about 7% became infected with HIV over three years, regardless of whether they were missing part of their penis.

circumcised and uncircumcised men showed no difference in the risk of HIV infection over three years.

while having unprotected sex with an HIV-positive partner increased a man's risk of infection, there was no evidence that circumcision altered that risk.

The report also makes clear that no previous studies have found circumcision helpful in preventing HIV in gay men, either:

There has so far been no good evidence that circumcision lowers HIV risk among these men.

Despite all the speculation, hope, and expense aimed at discovering that it does, there is no evidence that reducing the penis also reduces HIV infection. There is, however, good evidence that it does not.

But those looking for such a link still have hope. If only they could receive more funding, and perform larger studies, perhaps they may find that if gay men only had their foreskins removed, they might get less HIV.

This hope can be seen in the language in the story, which reflects the views of the researchers who would like more funding to perform more studies. Let's compare what is actually known with what is stated:

evidence that circumcision does nothing --> "may not do much"

evidence that circumcision clearly did not help --> "unclear"

circumcision made no difference --> "may not make much difference"

Is this simply the sort of sensible caution which should always be applied to medical study results? If so, we would expect the same caution to be applied to the evidence which found reduced HIV transmission to heterosexual adult men in Africa. Those findings should be similarly stated with prudent scientific uncertainty. Let's see what the same article says about those studies:

A number of studies in African nations have found that circumcised heterosexual men were up to 60 percent less likely than uncircumcised men to contract HIV during the study periods.

Nope. It's not even-handed caution. Evidence which favors circumcision is stated as a fact. Despite weaknesses in those studies, there's no hedging whatsoever. No admission that they could be wrong. No call for further evidence. But when evidence emerges that circumcision is useless, the headline tells us it still may work, and the researchers tell us it needs more study.

future studies, with larger samples of uncircumcised men, should continue to look at the question of circumcision and HIV transmission among men who have sex with men.

I'm just going to come out and say it. Some of these researchers have a cultural bias. They favor circumcision for reasons unrelated to HIV prevention, and they want more funding to study circumcision. Some of the reporters, too, are culturally biased to accept information favorable to circumcision.