Study: Little difference in violence between PG-13 and R-rated films (KPCC, Southern California Public Radio, December 9th, 2013)
Violence in PG-13 Movies Frequently Followed by Sex & Drinking, Study Finds (IMDb News, December 9th, 2013)
Don’t tell mom and dad: PG-13 movies are just as violent and sex-filled as R-rated ones (TIME.com, December 9th, 2013)
Violence, risky behavior a common mix in big films, study says (The Los Angeles Times, December 9th, 2013)