The improvement of the depiction of LGBT characters in films and television may have taken place on screen in past years, but a new study has found that it has not stopped LGBT actors from experiencing discrimination in Hollywood.

The Screen Actors Guild (SAG) and American Federation of Television and Radio Artists (AFTRA) commissioned the survey, which found that over half of LGBT actors feel that directors and producers are biased against them.

Released on Friday, the survey also found that over a third of actors who do not identify as LGBT agree with that perception.

16% of LGBT respondents said they had experienced discrimination, with around 20% of gay men they had experienced discrimination.

The online survey of almost 5,700 SAG and AFTRA members also found that over half of LGBT actors had heard producers and directors making homophobic comments while working on set.

Despite concerns about being typecast, the survey did recveal that two-thirds of gay actors who had played gay characters did not feel it had harmed their careers or limited the roles they were subsequently offered.

However, 9% of gay and lesbian people had said they had been turned down for roles over the past five years because of their sexual orientation.

“The survey results show both progress and indications that more work will be necessary to make the workplace an equal and fully welcoming place for LGBT performers,” M V Lee Badgett, a University of Massachusetts, Amherst economics professor affiliated with the UCLA institute.

“The good news is that almost no one thought that opportunities for LGBT actors were getting worse.”

Of the 5,692 participants, 465 identified as gay men, 61 as lesbians, and seven as transgender. Another 301 men and women described themselves as bisexual.

The study was conducted by the Williams Institute, a think tank based at UCLA that specialises in sexual orientation, gender identity and public policy.

The union had pursued the research, the first of its kind, at the request of a committee which represents LGBT members.

The full survey is available to view at the Williams Institute website.