A total of 221 young people in Scotland have been waiting more than a year for specialist help with mental health problems, new figures have shown.
The statistics – classed as "management information only" as they have not been assessed by statistical regulators – also disclosed there were 197 cases where children were treated on adult wards in 2017-18.
Concerns about students' mental health in Scotland led in September to an announcement of plans to provide a counsellor in every secondary school in the country.
The new figures that that in 255 cases, patients were admitted to child and adolescent units for treatment.
The figures on inpatient admissions were released at the same time as official data showing just four out of 14 health boards in Scotland met the target of having 90 per cent of youngsters accepted by Child and Adolescent Mental Health Services (CAMHS) start treatment in 18 weeks.
At the end of September this year, 7,860 children and young people were waiting for help, including 221 who had been on the list for 53 weeks or more.
That compares with 48 patients who had been waiting this long 12 months previously.
The Scottish Children's Services Coalition said the data showed "we are continuing to fail many of our children and young people with mental health problems". The body, which brings together organisations working with vulnerable youngsters, hit out at the government’s failure to invest enough in CAMHS despite the fact that the equivalent of three children in every classroom has a clinically diagnosable mental health problem.
CAMHS receives less than 0.5 per cent of the overall NHS budget. However, the Scottish government argued that it was investing an additional £250 million into mental health to support measures such as counsellors in every secondary school, improved training for teachers, and more nurses in schools and counsellors in universities and colleges.
The spokesman for the Scottish Children's Services Coalition said: "No longer can mental health be viewed as a 'Cinderella service' and we must put money behind the rhetoric if we are to just keep pace with investment south of the border.
"It is clearly disappointing to note these newly released figures highlighting that the NHS in Scotland, including ten of our health boards, are failing to meet what is already a lengthy waiting time.
"This is no coincidence given that a very small proportion of the overall NHS and mental health budget is being spent on addressing the needs of children and young people, and yet we know that three children in every classroom has a clinically diagnosable mental health problem.
"There must be a radical transformation of our mental health services, with a focus on preventing such problems arising in the first place and intervening early, especially when we know that half of all mental health problems begin before the age of 14."
Liberal Democrat health spokesman Alex Cole-Hamilton described it as a "disgrace" that the number of youngsters waiting over a year for help was on the rise.
He said: "Mental ill health among this age group is at crisis levels.
"Waiting so long for a substantive intervention can have a devastating impact on them and their families.
"Staff are working around the clock but they aren't getting anywhere near the support and resources they need. As a result, in some areas just one in three children are treated on time.
"The CAMHS budget must be boosted, mental health beds need to be established north of Dundee and every GP surgery and A&E in the country should have a mental health practitioner capable of treating people.
"That is the level of investment and ambition required if the government is to stop failing a generation of young people."
A Scottish government spokesman said: "We're clear that we must continue to build services in the community to meet significantly rising demand and take pressure off specialist services.
"That is why we're investing an additional £250 million into mental health to support measures such as counsellors in every secondary school, improved training for teachers, and more nurses in schools and counsellors in universities and colleges.
"While new waits for specialist treatment still fall well short of our expectations, half of children and young people are starting treatment within 12 weeks."
He added: "Any young person referred to mental health services should be assessed in the period prior to treatment starting, and we expect health boards to provide appropriate support during that period."