CHICAGO (Reuters) -- You think that PG rating means the film at the local multiplex is appropriate viewing for your 10-year-old? Think again.
A new study shows that one in five films rated PG, or "parental guidance suggested" -- with some material that may not be suitable
for children -- actually have more violent actions than the average for those listed as PG-13, or inappropriate for children under 13.
It also found that one in 10 PG films had more violent acts than the average for those in the study that were rated R, or "Restricted" -- meaning any viewer under 17 should be accompanied by an adult.
"The most striking finding was that more than one quarter of the violence in each of the three rating categories was of lethal magnitude," said the report from the School of Film, Television and Digital Media at the University of California, Los Angeles, on a review of 100 top-grossing films.
The Motion Picture Association of America rating system provides secondary information on violence, nudity and language, but it is often in the background in advertising. Thus parents who rely on the age-based categories are using what Theresa Webb, one of the report's authors, called "the weakest of all the indicators" to make viewing decisions.
However, even the secondary content listings for nudity and the like "are not completely reliable. Many films that were rated primarily for language were in fact just as violent as films that were rated for violence," the study said.
The association said its movie ratings were designed as an "advance cautionary warning" and suggested parents consult reviews, friends and other sources in deciding which movies they want their children to see.
The findings were published in the May issue of Pediatrics, the journal of the American Academy of Pediatrics. The authors suggested the industry needs to provide more consistent information on violent content and add a "quantitative component" to the ratings -- to better describe how much violence is involved.
The system "should determine the frequency and seriousness of the violent acts, the frequency and types of problematic language use, the frequency and graphicness of sexual representations," the report said.
Such descriptives could lead to numerical values that would make the ratings more precise and consistent, as opposed to such current "vague qualifying terms" as "some," "strong," "mild," "moderate," "brief" and so on, it added.
The report also said content descriptions should be made "clear and legible on all print advertisements and on all film, video, and DVD trailers."
The study reviewed the 100 top-grossing films of 1994, including "Ace Ventura: Pet Detective," "Dumb and Dumber," "Four Weddings and a Funeral," and "Pulp Fiction."
Webb said there have been no structural changes in the rating system since 1994 and "We feel it is still a representative sample and indicative of what's going on."