A new study finds about 20% of adolescents had major depressive disorder in 2021, but less than half of teens who needed mental health treatment had received any.

The findings come from a study of more than 10,000 teens ages 12 to 17 who were part of the National Survey on Drug Use and Health. Treatment was lacking most for teens in minority groups, especially those who are Latino and mixed race, The New York Times reports. The study found 14.5% of Black teens, 14.6% of Asian teens, 20% of white teens and 23% of Latino teens reported symptoms of major depressive disorder.

Major depressive disorder is a chronic condition that causes episodes of depressed mood and loss of joy. Symptoms last at least two weeks. Previous studies found the prevalence of major depressive disorder among teens almost doubled between 2009 and 2019. The pandemic intensified this trend, causing isolation, uncertainty, loneliness and fear of illness among family, the researchers said.

The study found only 21% of mixed-race teens and 29% of Latino teens with major depressive disorder received treatment for it, compared with nearly half of white teens.