The AVI left me an interesting link on my last post on famous social psychology studies that have not been replicated. It's good reading....they include the famous study that found that teacher's expectations being self fulfilling (ie kids achievement went up or down based on how smart the teacher thought they were). That was interesting to me, as I've heard that study quoted many times, and never heard that larger studies had failed to replicate it.
Anyway, as I was reading that article, a headline for another article floated across the top of the screen "Sleeping more than 7 hours or less than 5 1/2 hours has been found to decrease longevity".
I don't even have to read the article to tell you no study found any such thing.
The only way you could actually prove that is to randomize three groups, force one to sleep more than 7 hours, one to sleep between 7 and 5.5 hours, and one less than 5.5 hours per night (for the rest of their lives) and then see how long they lived. No one did that. We know no one did this.
Sure enough I clicked on the article and found that people who reported getting more than 7 hours of sleep/night were 12% more likely to do within 6 years than those who got slightly less (again, with the raw numbers the 12% increase might not be that impressive....how many otherwise healthy people died in the 6 year time period to begin with?). So there is a correlation, but no one proved what caused it. The most obvious caveat is that people who are sick might sleep more.
Why oh why do people still write headlines like this? I can see it when it's on the front page of Yahoo.com or something, but shouldn't Psychology Today have slightly higher standards?