Correlation of Movie Ratings With Content

"Parents and physicians should be aware that movies with the same rating can differ significantly in the amount and types of potentially objectionable content. Age-based ratings alone do not provide good information about the depiction of violence, sex, profanity, and other content, and the criteria for rating movies became less stringent over the last decade. The MPAA rating reasons provide important information about content, but they do not identify all types of content found in films and they may particularly miss the depiction of substances."