For anyone who has missed it, a couple of days ago NPR reported (in a fairly salacious way) that in a study of films from the 1950s onwards it was found that PG-13 rated films contained more gun-based violence than higher rated films. The study has angered some folk. I am less bothered on a personal level because the whole affair comes across as another lazy effects argument.
The study does not demonstrates that PG-13 films are 'more violent' than R-Rated films (as Shute implies). Rather, the study demonstrates that on average PG-13 films contain a higher quantity of a particular kind of violence. It tells us nothing of the qualitative nature of violence, including: a) how graphic the depictions are, b) the extent to which injuries are dwelt upon, c) emotional ramifications for characters, d) contextual cues such as previous actions and dialogue, d) how form (framing, music, and so forth) underline or complicate those meanings, and so on.
These elements are not extraneous, but rather are part of meaning-making. Film is not simply a collection of images - it has a language that seeks to appeal to viewers on an intuitive level. The sooner researchers such as Bushman, Jamieson, Weitz and Rohmer account for the qualitative nature of narrative film-making, the sooner I'll stop yawning.