Half of the estimated 7.7 million U.S. children with a treatable mental health disorder do not receive treatment from a mental health professional, according to a new study.

Researchers analyzed a national survey given to parents of children and teens. They found 7.7 million of the 46.6 million children ages 6 through 18 whose parents completed the survey had at least one treatable mental health condition, such as depression, anxiety or attention deficit/hyperactivity disorder. Only half had received treatment or counseling from a mental health provider in the year before the survey was conducted, CNN reports.

Treatment rates varied widely by state, the researchers wrote in JAMA Pediatrics. The number of children with a diagnosed mental health condition who did not receive treatment ranged from 29.5 percent in the District of Columbia to 72.2 percent in North Carolina.