A new study shows that movies have more violence in them than ever — or at least, movie characters are more interested in talking about it.

Published as a research letter in JAMA Pediatrics Monday, the study applied machine learning to a trove of 166,534 transcripts of films, charting how often words like “murder” or “kill” appear in spoken dialogue across five decades of cinema.

The result: Across all genres, researchers say so-called “murderous verbs” have become more common, in a trend that may reflect a rising interest, or perhaps a fading squeamishness, to on-screen violence.

“References to killing and murder in movie dialogue not only occur far more frequently than in real life but are also increasing over time,” said lead author Babak Fotouhi in a release announcing the study results.

“This is more evidence that violence is a bigger part of the movies we watch than ever before.”

Brad Bushman, another contributing researcher based at Ohio State University, said violent language is more common even in films without crime as a central focus.

“Characters in noncrime movies are also talking more about killing and murdering today than they did 50 years ago,” he said. “Not as much as characters in crime movies, and the increase hasn’t been as steep. But it is still happening.”

Murder, she spoke

Another particular trend of interest in the study was the increasing representation of female characters using violent language. While women in film account for less of the “They murdered him”-s than their male co-stars, the study showed a rising usage of murderous verbs by female characters throughout the data set as well.

Parallel research on gender in film shows that the under-representation is hardly limited to punch-ups and shootouts.

A separate 2016 analysis by culture writers at digital data journalism site The Pudding estimated that across 2,000 screenplays between the 1980s and 2010s, more than 1,500 had a significant majority of their dialogue spoken by male characters. In dozens of films found in that data set, nearly every single word in the script was uttered by a man, a phenomenon particularly common in action movies.

Yet another review of close to 1,000 scripts at the University of Southern California found more than twice as many male characters as female ones, with more than twice as many spoken dialogues between them. Female dialogue was more likely to be positive in nature, while male characters spoke more often about death, and were generally more vulgar in their speech.

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The researchers behind the study published Monday note that there are caveats.

The study authors narrowed their focus to active, affirmative uses of the violent language, including phrases like “She killed X,” and ignoring those like “He was killed by X,” “Did she murder X?” or “She didn’t kill X.”

All told, deadly verbs fitting those criteria appeared in seven per cent of movies in the data set, but the researchers say that likely doesn’t capture every last veiled threat, cry of terror or jaw-dropping murder accusation.

“We focused exclusively on murderous verbs in our analysis to establish a lower bound in our reporting,” said Amir Tohidi of the University of Pennsylvania. “Including less extreme forms of violence would result in a higher overall count.”

While the study authors say this database is among the largest ever examined for movie mayhem, contemporary research shows similar upward trends in the amount and nature of violence allowed on-screen.

A previous study co-authored by Bushman found that in films rated PG-13, gun violence in particular has tripled since the rating’s invention in the mid-1980s, with violence of all kinds found in those films even eclipsing the amount in R-rated movies. Fictional violence more-than doubled between 1950 and 2013, the study showed.

“Movies are trying to compete for the audience’s attention and research shows that violence is one of the elements that most effectively hooks audiences,” Fotouhi said of the Monday study’s results.

And while the rise in violence has progressed for decades thus far, it’s not clear what cultural or industry-level shifts could bring in the years to come.

“The evidence suggests that it is highly unlikely we’ve reached a tipping point,” said Bushman.