Despite historic gains in visibility and equality for lesbian and gay people, youth who do not identify as straight continue to face high levels of violence, bullying and sexual assault, according to a new study.

The findings provide an unprecedented look at the torment some lesbian, gay and bisexual youth experience compared to their straight peers. The study also marks the first time the Centers for Disease Control and Prevention has asked about sexual identity in its national Youth Risk Behavior Survey of high school students.

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"What we have to understand is that young LGBT people have immense barriers placed in front of them to their success," Sean Kosofsky, the executive director of the Tyler Clementi Foundation, an anti-bullying organization, told Mashable. "Not only in finishing school, but in finishing their day."

Of the students surveyed, 2% said they were gay or lesbian, 6% identified as bisexual and 3% were unsure of their identity. The latter group also frequently felt unsafe at school and experienced levels of violence similar to or even higher than lesbian, gay and bisexual students. The survey did not inquire about gender identity, though researchers will likely incorporate that into future versions.

The questionnaire, given to students in grades 9 through 12, included more than 100 health-related outcomes and behaviors including bullying, violence and drug and alcohol use. More than 15,000 students took the survey.

Thirteen percent of gay, lesbian and bisexual students said they had not attended school at least once during the previous 30 days because they feared for their safety; only 5% of straight students reported doing the same.

"[Young] LGBT people have immense barriers placed in front of them to their success."

A third of those who identified as gay, lesbian and bisexual had been bullied on campus compared to 19% of straight students. Bullying via email, chat rooms, instant messaging, websites and texting was similarly prevalent. Students who weren't sure about their sexual identity experienced much higher rates of fear and harassment than straight youth.

The incidence of aggressive behavior may surprise some who see a surge in anti-harassment campaigns and laws, but those initiatives may not be widely effective or successful.

Emily Greytak, the director of research for the advocacy organization Gay, Lesbian and Straight Education Network (GLSEN), said that while things generally seem to be improving for youth, "it's still shocking how often homophobia is rampant."

GLSEN's research has found that even when anti-bullying policies are in place, they may not specifically protect a student's sexual orientation. Teachers may also lack the training and skills to respond to anti-gay bias and harassment. Similarly, state laws may go unenforced.

The failure to stop violence that targets lesbian, gay, bisexual youth and students unsure of their sexuality appears to have devastating consequences.

Many LGBT youth continue to face #bullying each day. Here's one #Upstander's story about #homophobia in the '70s: https://t.co/px40gShoPG — Tyler Clementi Fndtn (@TylerClementi) August 12, 2016

Larger numbers of those students said they felt sad, hopeless and suicidal. While 5% of straight students reported being forced to have sexual intercourse, that figure reached 18% for gay, lesbian and bisexual students, and 13% for the unsure students, a statistic that Greytak said might be related to the students' perceived vulnerability.

More of the LGB students had also used alcohol, cigarettes and drugscompared to straight students. While the study doesn't attempt to explain the disparities, Greytak believes the drug and alcohol use may be a coping mechanism for youth who are trying to manage bullying and feelings of worthlessness. It might also indicate that prevention materials and treatment programs aren't effectively reaching lesbian, gay and bisexual youth.

What it should not suggest, she said, is that a student's sexual orientation causes risky behavior: "There’s nothing wrong with LGB youth at all. What’s wrong is a society that tells LGB youth there’s something wrong with them."

"We need constant constant diligence and education to maintain the gains we’ve made."

Greytak hopes the study will encourage educators to evaluate their own policies and ensure that staff receive curriculum and training to help prevent harassment.

Kosofsky said that despite legal victories like same-sex marriage, he is unsurprised by the study's findings. "Although we’re making progress in terms of overall climate, that does bring backlash," he said.

The results, he added, should prompt adults to talk openly and honestly with young people about how they treat peers who are different. Students can also reflect on the importance of interrupting discrimination as a bystander, reporting such incidents to trusted adults and reaching out to the victim.

"We need constant constant diligence and education to maintain the gains we’ve made," Kosofsky said.

This story was updated on Aug. 15 at 2:34 ET to clarify that the study is based on the CDC's national Youth Risk Behavior Survey and to correct the percentage of straight students bullied on school property. The original figure of 14% reflected straight students bullied electronically.

If you want to talk to someone or are experiencing suicidal thoughts, text the Crisis Text Line at 741-741 or call the National Suicide Prevention Lifeline at 1-800-273-8255. For international resources, this list is a good place to start.

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