The Journal of the American Medical Association has released a study that violence in G-rated films is on the rise. Two researchers from the Harvard Center for Risk Analysis looked at all 74 G-rated films released on video prior to September 1999. The report lists at least one act of violence in every film; 46 films contained at least one character injured and over half of the 74 films had a character killed. The movies averaged 9.5 minutes of violence, up from 6 minutes in 1940. "A G-rating does not automatically signify a level of violence acceptable for very young viewers. The MPAA (Motion Pictures Association of America) should consider changing the current age-based rating system to one based on content, which is what an overwhelming number of parents prefer," the study says. "Parents need to preview films themselves or use on-line resources to judge appropriateness of individual films for their children." Like the SOUTH PARK feature lampooned, the study states that the MPAA is more focused on shielding children from sex than violence. Fumie Yokota, co-author of the study said cartoon violence is supposed to be slapstick but "it may desensitize kids so much, they think it's okay and no big deal for somebody to be smacked in the head with a hammer." The report listed QUEST FOR CAMELOT as the most violent general audience film, with 24-minutes of violence, about 30% of the film. The study noted A GOOFY MOVIE, KIKI'S DELIVERY SERVICE and MY NEIGHBOR TOTORO as having below-average violence. Another worthwhile note is that the study revealed that violent acts by the good guys are portrayed in a light or funny tone (i.e. Dumbo shooting peanuts at the ringmaster), whereas the bad guys' violent acts are viewed as dark or sinister (i.e. the hunter killing Bambi's mother). The study concluded, "content analysis reveals a striking behavioral message implied by many of the G-rated animated films that the good guys triumph over the bad through the use of physical force." Subsequently, MPAA president Jack Valenti disputed the study stating that the rating system, in place since the late 1960s, consistently receives "high approval marks" from parents.