Children's cartoons depict death more often than films for adults, and their main characters are more than twice as likely to be killed off, according to research released on Tuesday.

The study found the main characters in children's cartoons were two and a half times as likely to die as protagonists in films for adults, and were almost three times as likely to be murdered - often in violent ways.

Important characters overall die in two-thirds of cartoons aimed at children, compared to in half of films for adults, according to the study published in the British Medical Journal.

"Rather than being innocuous and gentler alternatives to typical horror or drama films, children's animated films are, in fact, hotbeds of murder and mayhem," said study researchers Ian Colman and James Kirkbride.

The study analyzed top-grossing children's cartoons from Snow White in 1937 to 2013's Frozen.

It compared deaths of main characters with the two top-grossing films for adults released in the same year, not including action or adventure films marketed to children.

It found the parents of main characters were five times as likely to die in children's cartoons than in films for adults.

Notable deaths included the shooting in Bambi and attacks by animals in Finding Nemo and Tarzan.

Films featuring animated cars and toys were not included as it was not clear that the concept of death exists for such characters.

AFP