Friday, December 18, 2009

Mohawks preferred over other hairstyles: study

Those claiming to do science sometimes fail. One way they may fail is by profound selection bias. For example:

Perform a study in which volunteers receive a free head shaving leaving only a strip of hair down the center (Mohawk). Ask participants how they feel about their hairstyle before and after. Find that more participants like their Mohawk better than their original hairstyle. Conclude Mohawks are very well liked compared to other hairstyles.

Really? Are Mohawks so well liked, or is there another explanation? Can you really walk down the street and Mohawk a random person and expect them to prefer it? No, but if you put up a "free Mohawk" stand along the street and let participants self-select, then yes, volunteers probably will like it.

And so it is here:

Sex equally satisfying with circumcised men: study

They put up a sign: "Free circumcision" for your partner when you both participate. Some couples selected themselves to participate. Women who recognize the positive role their partner's foreskin plays in their sexual experience didn't sign up. Men who find their foreskins lots of fun didn't sign up, either. Couples who wanted their male circumcised could sign up for one at no cost (although may need to wait for it). It's a profound bias.

Bad science happens. Science is good because the bad science is eventually seen for its flaws, but very bad policy may result more quickly.

Bailey said the finding might also help counter a growing reluctance of some parents to have their infant sons circumcised. "In the US, there is currently a strong movement against circumcision, especially on the West Coast," he said.

I (@IntactByDefault on Twitter) have an agenda, and that is for freedom from non-therapeutic circumcision to be recognized as everybody's right (hence the #i2 campaign). I am a part of this growing reluctance to deprive children of their right to choose genital integrity. Others have their own agendas. Some even want the world Mohawked.


If you think this blog post helps shine light on how bad science may influence bad policy, you are welcome to republish it in its entirety.


  1. The level of sexual satisfaction was not determined by objective evidence, but by the women answering survey questions before and after the circumcision was performed on their male partners. The published study provides no information on what the questions were. See:

    The published study provides no information on when the women were surveyed after the circumcision was performed. Was it shortly after the circumcision wound healed (when the guys would be horndogs because it has been weeks since they had sex) or was it after a several months or more?

    Nor does the study identify the survey questions used to determine the self-reported sexual satisfaction levels.

    The researchers wanted to prove that circumcised guys could still satisfy women. And, they proved it, one way or the other.

    This study is just one more example of bad science. See Why Most Published Research Findings Are False:

  2. Their are other reasons also, given circumcision removed a functional sex organ, the men took longer to argasm, leaving the women feeling they had longer sex and therefore more satisfied. The issue their is selfishness and not circumcision status, the circumcision made the men iunadvertantly less selfish, being less selfish can be achieved without circumcision.

  3. Intact by Default you make an important point on this. None of the trials into circ and HIV in Africa can be seen as objective. The RCTs themselves took mainly unemployed men and paid them to participate in a programme they knew was designed to promote circ as a good thing. The Cochrane people - neutral reviewers -acknowledged there was a risk of bias in the studies.

    The sexual satisfaction 'data' comes from the same stable. AIDSMAP were slightly scathing about the strange result which emerged from Krieger's study of male sexual satisfaction post circ....They pointed out that the fact that most erectile dysfunction melted away during the trial (in cut and uncut) indicates the men were "wishing to please the researchers". They indicate all the findings should be seen with caution in the light of this. We should see the female satisfaction survey in the same light - particularly as it contradicts previous research.

    Re Ian's point, where on earth do men get this idea that for women to enjoy sex it just has to be longer....? Lengthy sex is a pain, quite literally. We need stimulation in the right place which IMO is partly what the foreskin is there for... Have you never wondered where they got the idea for those 'for her pleasure' condoms which have ridges, like skin bunching up below the glans?

    Check out Solinis research - he asked couples in which the man had undergone an adult circ during their relationship what they thought. The women were even more likely to be unhappy than the men. Although most found there was a delay in orgasm only a small proportion considered this beneficial.