LOS ANGELES: Aside from action star Dwayne Johnson's hit movies, Hollywood's most popular films have rarely featured Asians or Pacific Islanders in leading roles on the big screen, according to an academic study released on Tuesday.

The findings showed "an epidemic of invisibility" for Asians and Pacific Islanders (API) in movies released from 2007 to 2019, said the study from researchers at the University of Southern California's Annenberg Inclusion Initiative.

They also said the under-representation and stereotypical portrayals may have contributed to recent incidents of violence and harassment against Asians in the United States.

About 7.1% of the U.S. population identifies as Asian or Pacific Islander. In the 1,300 top-grossing films during the study period, 3.4% of leads or co-leads were played by API actors, the researchers found.

Of 44 films with API actors in leading roles, 14 of them starred Johnson, the former wrestler known for the "Fast & Furious" and "Jumanji" films. Johnson's mother is from the Pacific island of American Samoa.

Six movies featured a female API character in a lead role, the study said.

The report adds to research that has found under-representation of women, people of color and LGBTQ characters in movies and television. In response, Hollywood studios have pledged to increase the diversity of people in front of and behind the camera. Notable recent films included 2018 romantic comedy "Crazy Rich Asians" and 2020 action film "Mulan," both with large Asian casts.

While the study found the number of API characters lacking, the researchers also criticized the way many of them were portrayed.

Sixty-seven percent of API characters were shown as "the perpetual foreigner" with a non-American accent, were hyper-sexualized, subject to racial slurs or fell into another stereotype, the researchers said.

"Mass media is one factor that can contribute to aggression towards this community," said USC professor Stacy L. Smith, founder and director of the Annenberg Inclusion Initiative. "When portrayals erase, dehumanize, or otherwise demean the API community, the consequences can be dire. Without intention and intervention, the trends we observed will continue."

The study was conducted by the Annenberg Inclusion Initiative with sociologist Nancy Wang Yuen. It was funded by Amazon Studios and the UTA Foundation.