By Pat Loeb
PHILADELPHIA (CBS) -- When Indiana Jones and the Temple of Doom came out in 1984, many parents were horrified that the PG movie exposed their children to so much violence, torture, live eviscerations and human sacrifice.
The Motion Picture Association of America (MPAA) responded with a new rating: PG 13 would warn parents that there was more violence than in a PG movie but not as much as in an R movie.
However, a study of movies released since then, and published Monday by the journal Pediatrics, shows violence in the PG 13 movies has escalated so much, the rating has lost its meaning.
"It was comparable to PG when it first started but over the years, it just steadily increased," says Dan Romer, director of the Adolescent Communication Institute of the Annenberg Public Policy Center and co-author of the study, "so now it's three times greater than it was when it started and the astounding thing is, it's actually higher in PG 13 than it is in R."
The MPAA still considers sex and language in rating a movie R.
Studios will often tone down those elements to keep a PG-13 rating for movies, which generally tends to do better at the box office than R movies.
There's no incentive to curb violence, though Romer believes it's at least as harmful as depictions of sex.
Studies on the effect of movie violence are inconclusive: Some find it leads to violent behavior; others say it has no effect.
Romer, though, sees clear evidence that movie violence can be unhealthy in the real life example of James Holmes, who told police he was "The Joker," an extremely violent character from the PG-13 movie "The Dark Knight," after he opened fire in a Colorado theater killing 12 people during a screening of the movie's sequel.
"Why not put an R rating on them to at least alert parents to the fact that maybe this is just as harmful as what they do with sex," says Romer.
The MPAA declined comment on the study.
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