Seven out of 10 British cinemas offered no subtitled screenings for the summer’s most popular children’s films, according to research by a charity which says deaf youngsters in the UK are being failed by chains that are too slow to adopt new technology.

The National Deaf Children’s Society’s research shows the top 11 children’s films were shown in an average of 581 cinemas, with only 171 cinemas providing at least one subtitled screening.

“This research couldn’t be clearer – deaf children across the UK are being denied a key part of their childhood because cinemas are refusing to put on subtitled performances,” said Helen Cable, the director of children, young people and families at the charity.

“The remedy couldn’t be more straightforward: cinemas need to increase the number of subtitled films they show, and show them at times that are more convenient for families.”

The charity also recommended investment in new technology – such as tablets with subtitle technology and smart-caption glasses which are in use at the National Theatre – that would, it says, transform the cinema experience for deaf children. “None of this is rocket science but its impact would be enormous,” Cable added.

The Lion King was the best performing children’s film this summer, with 48% of cinemas surveyed in the research providing a subtitled screening, while The Queen’s Corgi (10%) and Ugly Dolls (5%) were the films that had the fewest subtitled screenings. The research looked at UK cinema screenings from May to August, and found that when a film did have a subtitled performance, often there was the only one offered.

Rachel Shenton, the actor and film-maker who won the Oscar for the best live-action short film with The Silent Child last year and gave her winner’s speech in British Sign Language – called for more facilities to be provided for deaf children at cinemas. “It’s unacceptable that deaf children across the country struggle to access the cinema,” said the director, who began learning sign-language at the age of 12, after her father went deaf.

“In my home town of Stoke-on-Trent, all the staff at the local Odeon cinema have had basic sign language training and show regular signed and subtitled films – so it can be done.

“The people running these cinemas need to look deaf children in the eye and tell them why they can’t have a childhood like other kids. Things need to change, and it’s shameful that they haven’t already.”

Carlene Alexander, who lives in Harrow with her daughter who has been deaf since birth, told the Guardian that the lack of subtitled screenings means when she does find them they are often at an inconvenient time or involve travelling to another town. “Not providing subtitled films doesn’t only mean deaf people miss out on the films,” she said. “It means they are given the message that mainstream culture isn’t interested in them and that they are not welcomed.”

Cineworld states that it shows subtitled screenings based on “the availability of specially adapted films as well as customer demand”, while Vue, Showcase and Odeon all flag up their commitment to captioned and subtitled screenings on their websites.

The UK Cinema Association, an industry body that represents more than 90% of UK cinema operators, said it is working with a number of its larger cinema operator members to “explore the audience response to increasing the number of subtitled screenings available”, including for children’s films.

“UK cinema operators very much understand the desire of deaf and hard-of-hearing customers, as well as other disabled audience members, to enjoy the big screen experience,” a spokesperson added. The organisation is working with the National Theatre to see if the smart-glasses technology in use at the NT can be transferred to the cinema industry.