Tuesday, November 04, 2003

Laughter: The Best Medicine

The United Nations is upset with the Church again.

What a (yawn) surprise.

Recently, Cardinal Trujillo pointed out the obvious: condoms do not protect against HIV. Though he simply echoed the point several dozen secular experts have made for years, namely, that HIV is several dozen times smaller than the smallest holes in a latex condom, and therefore not effective, the press immediately took offense.

The World Health Organization disagreed. “When you use a condom badly so that it breaks or slips or it is past its 'use-by date' it is not very effective," spokeswoman Fadela Chaib said. "Two years ago, in June 2001, there was a big study that reviewed all the literature on male condoms. This study showed that condoms are 90 percent effective against HIV/AIDS infection, and the other 10 percent is when they were used wrongly.”

Unfortunately, the ‘big study” Miss Chaib refers to says nothing of the sort. Open up a new browser window, point it at http://www.niaid.nih.gov/about/organization/dmid/documents/condomreport.pdf and follow along for the fun.

The “Assessment of Data” on page one admits that the scientific literature is inadequate: the experts simply don’t know how effective condoms are in preventing STDs. Certainly Miss Chaib would have bothered to read the first page? But wait. It gets better.

By page 2, the government study is insisting that, though it can’t be certain about how effective condoms are with any other STD, it knows for sure that condoms are effective against HIV. Well, let’s see their reasoning.

The experts collected all the studies on condom use they could find, then examined and compared them in what is called a “meta-analysis”. Note their warnings on pp. 5-6, particularly conclusions 6 and 9. “Most studies” did not provide useful information on condom usage or on exposure to disease. So, they admit their meta-analysis isn’t really based on 138 studies, it’s actually based on just “a few” – how few, they won’t tell us.

By page 9, they admit that most studies they used are older (they don’t include newer, ostensibly higher quality condoms), they rely heavily on user recall of events and self-reporting, and they cannot be considered rigorous. Yet, these older studies tend to be all anyone has. They end by estimating that the newest condoms have only a 3% failure rate, but the statistics they include in their own report tends to corroborate the 10% to 30% failure rate given by the older studies.

Consider: On page 10, the study insists that couples using condoms correctly experience only a 3% failure rate. Their evidence? One rigorous study, consisting of user couples in a long-term monogamous male-female relationship who claimed a perfect use rate showed a 1.1% pregnancy rate for "consistent [condom] use" and a 6.3% pregnancy rate for overall condom use.

First, even a high school science jockey knows that one study does not prove anything. The whole point of science is to replicate results. If other researchers cannot replicate the results then the event didn’t happen, from a scientific point of view.

Second, even assuming this study was done perfectly and can be replicated, the actual pregnancy rate given in the study necessarily means the actual condom failure rate was at least four times higher. After all, sperm can only fertilize an egg that is present, and a woman can only get pregnant for about one week a month, on average. This "one week a month" takes into account that the egg is only able to be fertilized for a period of 24 hours (it disintegrates 24 hours after release), and that sperm can survive in the woman's reproductive tract for between three and five days. This also assumes there are no other problems inhibiting pregnancy: e.g., the man does not have a low sperm count, and the woman doesn't have other biological problems (scarred ovarian tubes, insufficient endometrial lining in the womb, etc.) that prevent implantation, etc.

Thus, if a condom study is using pregnancy rate to demonstrate condom effectiveness, the pregnancy rate is always going to be 1/4th the actual condom breakage, because the egg is only available for fertilization 1/4th of the time. If the experts want to assume that the pregnancy rate correlates exactly to the condom failure rate, they have to assume that condoms only fail when a woman has just ovulated or is just about to ovulate. That is, either condom using couples are only having sex during the woman's fertile period (one week a month), or the condom itself is able to maintain its own integrity when the woman is not fertile, but it somehow senses the woman’s impending ovulation and, unable to cope with the additional responsibility, slips or breaks. Obviously, both of these suppositions are absurd, and no one has ever asserted either of these things to be true.

So, the very pregnancy rates cited in the “one rigorous controlled trial” for "perfect use" condoms require that the actual condom failure rate has to be at least between 4.4% and 25.2%. Worse, these rates can only be this low if we assume all the people in the studies cited are in perfect health and able to conceive - something no one looks at in any condom study. Thus, we can safely assume that the condom breakage rate in the NIH approved study is most definitely higher than 4.4% to 25.2%. This is verified by the next few sentences: according to another study, 14% of couples experience an unintended pregnancy in the first year of use, which means these couples have an actual condom failure rate of at least 64%!

But wait! It still gets better!

The studies cited here are between “long-term monogamous male-female couples.” These couples have the time, the experience and most important, the motivation, to be deliberate and careful about their condom use. They think children will harm their sex lives, and they want to maintain their long-term relationship, so these couples are motivated to use condoms effectively. Will such motivation be present in a one-night stand man, who is moving quickly with the flow of the moment in order to get his new acquaintance's panties off? Will it be true of the homosexual using a "glory hole" in the public restroom, who gets his thrills in the danger of possibly being caught? Myriad other scenarios of a people engaged in similarly less deliberative situations could be brought forward. It seems unlikely that every couple would have the same success rate as a long-term monogamous heterosexual couple, who has a vested interest in not getting pregnant precisely because they want to preserve their long-term relationship and fear that pregnancy would somehow alter that relationship. NIH is cherry-picking their situations to get that 1.1% failure rate, and they know it.

They even admit it. The panel points out on p. 12 that none of the studies considered by the panel evaluated the rate of condom slippage or breakage in persons under 18 years of age. This is rather important, because other studies have repeatedly shown and already established that teenage condom use is associated with alcohol and drug use.

Put another way, teen risk behaviours travel in clusters. Consider the following group of risk-taking activities: smoking, alcohol use, drug use, sex. All researchers agree that if a teen engages in any one of the activities in that group, s/he is also much more likely to engage in at least one other activity in that group - if s/he regularly engages in two activities in that group, s/he is almost certain to regularly engage in three or four. That means that teens having sex are not infrequently going to be drunk or stoned while doing so. Now, what is the likelihood that a drunk or stoned teen will correctly use a condom? The panel deliberately ignored the teen population because it destroys their "condom failure" figures.

Finally, the WHO's own studies indicate that condom use is not all its cracked up to be in terms of AIDS abstinence. The only African nation which has seen not only the relative, but the absolute number of AIDS cases drop, is Uganda. Coincidentally, Uganda is also the only country that does not have a government condom distribution program. The Ugandan government relies on abstinence promotion to reduce AIDS cases.

So, let’s sum up. The experts admit that condom studies don’t prove anything, their own pregnancy rate numbers show a condom failure rate four times higher than they admit to, and they manage to get their low rate only by ignoring both teenage sexual practices and the practices of any other couples whose actual use would increase condom failure figures.

And they wonder why we laugh at them.

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