They took the raw data (which does show that people who take pledges have sex less than those who don’t), and massaged it.
Specifically, they decided that comparing “pledgies” with “non-pledgies” wasn’t rational, since pledgies were more likely to be people who wouldn’t have sex. So they looked for OTHER factors like upbringing, religion, etc, to “weight” the information.
Once they had “comparable groups”, they found that within a “comparable group”, those who took the pledge had sex just as much as those who didn’t, but those who took the pledge were less likely to have a condom or birth control.
Now, the 2nd part is simply common sense. If you have pledged not to have sex, you probably are not on the pill, and probably don’t have condoms around.
On the other hand, the idea that you can find comparable groups in which you can then differentiate between pledgers and non-pledgers is problematic.
For example, suppose you have two girls of similar looks and circumstances, both from conservative christian homes. Both are taught not to have sex before marriage.
Which of the two is more likely to “take the pledge”? The one that feels more drawn to having sex. The pledge is a tool to help you resist temptation. A girl who has no interest in sex may not feel necessary to take the pledge, the girl who is getting pressure to have sex might take the pledge to help fend off the pressure.
Which means that, absent the pledge, it is likely the “pledgers” would have more sex than the non-pledgers.
The point is that “taking the pledge” is not some independent variable. A person’s circumstances is what DRIVES them to take the pledge, or not.
If you took the pledge, I’d figure that you’d probably be in a monagomous relationship which right there would cut down on some STD factors.
Homosexuals are unlikely to use birth control as well and I doubt that abstinence or chastity pledges are even considered at the homosexual only public school that was established in Chicago recently.
If it is all about education, and we are told that homosexuals are smarter than the rest of the population, why is the message that engaging in random sexual encounters with strangers in washrooms without a rubber is hazardous? The message is ignored.
Taking the pledge is also a public declaration. There may be some students who take this same attitude to sex (wait) but are unwilling to make themselves a target of ridicule at the school. A shy nerd doesn’t need more things to be hassled over.