I picked up a copy of AM New York (free newspaper given out in the subway stations) yesterday morning. So we are told: tanning beds are killers. See here for example.
The article began:
The report found that the risk of skin cancer jumped by 75 percent when tanners started regularly using the beds before the age of 30.
A few paragraphs later, an "occasional tanning bed user" made a confession:
What started out as a relative increase in risk of 75 percent (those using tanning beds compared to those who don't) ended up as a 3 in 4 chance of getting cancer!
This reminds me of Joel Best's books in which he explored how data gets "adulterated" as it moves through society. I find his perspective fascinating and his books well worth a read. They are not your typical statistics book for sure.