Repeated identical methods across twelve years reveal genuine behavioral trends

Evidence

Another fairly unique feature of the Secret Survey studies, compared with other sex surveys, arises from my methodological and personal fixedness. I have accumulated data in the exact same way on the sexual behavior of the same kind of university students in the same place over the past twelve years. The results give us a good look at how things have changed over time, at least Nevertheless, I would not want to pass these results off as the answer to a sex surveyor’s (or voyeur’s) dreams. — Bob Altemeyer, The Authoritarian Specter, 2212