There is this article with a title:
"Tattoos and piercings are more common among those who experienced childhood abuse and neglect"
(not going to make a link for them)
What message do you get out of this title? — that most tattooed people were abused in childhood, don't you?
How about their conclusion:
> Results showed that around 40% of participants had at least one tattoo or piercing and approximately 25% of participants reported significant child abuse or neglect. Among the participants reporting child abuse, 48% had a tattoo or piercing, while only 35% of people not reporting child abuse had a tattoo or piercing.
It says that 48% were abused — almost half. Impressive, ha?
However, if you plot what they say, or recalculate, or rebuild the sentence, you get that:
only 12% are tattooed and were abused, and ~35% are just tattooed.
Just saying.
> and ~35% are just tattooed.
~35% (37% to be exact) not of all respondents, but of those who have tattoos (from those 40%).
From all respondents it would be 28% vs. 12%.