Queensland researchers have called for better sex education after a study of school leavers found that two-thirds did not know they could access emergency contraception without a prescription.

They have also called for a name change campaign, arguing that the colloquial term “morning-after pill” was the reason that 50% of the 498 teenagers who responded to the survey believed that emergency contraception was only effective for 12 to 24 hours after sex.

Only 18.5% knew that it could be taken up to 72 hours or up to 120 hours after intercourse, depending on the drug used.

The study was conducted at the wristband distribution centre on the first day of schoolies week on the Gold Coast in 2017 and published in the Journal of Pharmacy Practice and Research on Tuesday.

More than 13,000 high school graduates attend the festival in 2017 as a celebration of completing year 12, and the risk of unprotected sex is considered to be high.

The average age of the survey respondents was 17, and young women were up to three times more likely to have the correct information about emergency contraception than young men. Still, 23% of young women and 32.3% of young men believed emergency contraception was harmful to the user.

The lead author Denise Hope, from Griffith University’s school of pharmacy and pharmacology, said the evidence from previous studies was that awareness of emergency contraception did not improve with age.

“Generally awareness around emergency contraception is pretty poor,” Hope said. “Our interest in this cohort is that they were more of an at-risk group and arguably more likely to be involved in unprotected intercourse than older people who may still have poor awareness.”

Hope said the name “morning-after pill” was “a misnomer and potentially misleading”.

Levonorgestrel, an oral emergency contraception that is effective up to 72 hours after intercourse, has been available over the counter since 2004. Ulipristal acetate, which has continued efficacy up to 120 hours or five days after intercourse, has been available over the counter since February 2017. In Queensland, according to Women’s Health Queensland Wide, the cost is between $20 and $50.

Hope said the lack of sex education in high school, or lack of a consistent sex education program, as well a lack of advertising about the drugs, had contributed to poor awareness.

Both forms of emergency contraception were cleared for advertising by the Therapeutic Goods Administration, and Hope said targeted advertising, particularly social media advertising aimed at women of reproductive age, would increase awareness.

At the moment, she said, most young women come by information about emergency contraception through “osmosis”.

“It’s that woman-to-woman network,” she said. “But I think it’s really important that young men know as well. This information and awareness should not be just the domain of women, although arguably the consequences are greater for us so we give it more credence.”

Hope said many young men who were approached by the researchers to fill out the survey responded by handing the iPad to a female friend, because they thought it was a female issue.

Hope said emergency contraception should be taught as part of a broader safe sex curriculum.

“I think we are aware that not all sex is going to be safe even if people intend for it to be safe upfront,” she said.

“Contraceptive failure happens. Sexual assault happens. We want people to know that there are options afterwards if that happens to be the case.”

Queensland child safety, youth and women’s minister Di Farmer said the government received a recommendation on Friday from Griffith University to include information about emergency contraception on its Safer Schoolies website, and was considering that recommendation.

“The Palaszczuk Government will always take expert advice on the health and wellbeing of young Queenslanders seriously, and the topic of safe sex is no exception,” she said.