Haninger, K., & Thompson, K.M. (2004). Content and ratings of teen-rated video games. Journal of the American Medical Association, 291 (7), 856-865.

Abstract:  Quantified and characterized the content in video games rated T (for “Teen“) and measured the agreement between the content observed in game playing and the Entertainment Software Ratings Board (ESRB)-assigned content descriptors displayed on the game box. The authors created a database of all 396 T-rated video games released on the major video game consoles in the US by April 1, 2001, to identify the distribution of games by genre and to characterize the distribution of ESRB assigned content descriptors. We randomly sampled 80 video game titles, played each game for least 1 hour, quantitatively assessed the content, and compared the content we observed with the content descriptors assigned by the ESRB. Outcome measures were depictions of violence, blood, sexual themes, gambling, and alcohol, tobacco, or other drugs; whether injuring or killing characters was rewarded or is required to advance in the game; characterization of gender associate with sexual themes; and use of profanity in dialogue, lyrics, or gestures. Analysis of all content descriptors assigned to the 396 T-rated video game titles showed 94% received content descriptors for violence, 26% for blood, 15% for sexual themes, 14% for profanity, 7% for comic mischief, 2% for substances, and none for gambling. (PsycINFO Database Record (c) 2004 APA, all rights reserved)