The age that quietly ends care
Most people don't know it, but mental health care for young people has a hard cutoff. In many countries, around the time a teenager turns 18, they're expected to leave the child and adolescent system and join the adult one.
In practice, many of them don't make the leap at all. Care just ends.
A new study tested whether a structured handoff could change that — and the results suggest it can.
Mental health conditions in young adulthood — anxiety, depression, ADHD, psychosis, eating disorders — often need years of follow-up. Stopping treatment at the wrong moment can trigger relapse and erase years of progress.
Yet the system change happens at one of the most fragile points in life. The same person who needs care has just become a legal adult, may be moving for school or work, and is supposed to manage all of it on their own.
Most teens don't navigate that smoothly without help.
The old way versus the new way
The standard approach to transition is informal. The teen's child clinician writes a referral, the family is given some adult provider names, and the family is left to follow up.
This study tested a more deliberate approach called "managed transition." Clinicians are trained to spot teens nearing the cutoff, formally assess their readiness for adult care, and actively guide the handoff. The goal isn't to push everyone into adult care — some genuinely don't need ongoing treatment — but to make sure those who do actually get it.
Imagine a guided tour at a museum versus a self-guided walk. Both let you see the exhibits, but the guided tour ensures you don't miss the important rooms or get lost.
Managed transition adds the equivalent of a guide. The clinician identifies a teen as approaching the boundary, runs through a structured checklist with the family, and works with the receiving adult provider to set up the next appointment before the cutoff hits.
It's not glamorous, but it removes the most common reason teens disappear — that nobody on either side was watching for the moment to act.
The study snapshot
The MILESTONE trial enrolled 793 young people across 40 child mental health sites in 8 countries. About 552 received usual care and 241 received managed transition. The teams checked back in 15 months later to see who was actually receiving adult mental health care, and whether the transition was clinically appropriate.
In the standard care group, only 14.2% of teens had transitioned to adult mental health services at 15 months. In the managed transition group, that rose to 24.9% — nearly double.
When the researchers focused only on the teens who genuinely needed continued care, the gap got even wider. About 32.3% of these high-need teens in the managed group made the transition appropriately, compared to just 16.4% in the standard care group.
That's the difference between half of the kids who needed continued treatment falling out of the system, and only a third doing so.
This doesn't mean the gap is closed. Even with the best intervention, more than two-thirds of teens who needed care still didn't get it.
Where this fits in the bigger picture
Care transitions are one of the weakest links across all of medicine. The same problem shows up moving from pediatric to adult care for asthma, diabetes, congenital heart disease, and many other conditions.
Mental health is especially hard because the underlying illnesses can interfere with the very planning that makes a smooth transition possible. Teens with depression may struggle to schedule appointments. Teens with social anxiety may avoid meeting a new clinician.
This study is one of the largest tests of whether a structured intervention can make a measurable difference. The answer is yes — though there's plenty of room for further improvement.
If you have a teen receiving mental health care who is approaching the age cutoff for child services, this study gives you reason to push harder for a structured handoff.
Ask the clinician what their transition process looks like. If the answer is vague or only references a referral letter, ask whether there's a more formal program available. In many systems, you may need to advocate to get something closer to managed transition for your own teen.
The study compared sites, not individuals — meaning some of the difference may reflect how organized the participating clinics already were. Even with managed transition, three-quarters of teens still weren't in adult care at 15 months, suggesting the underlying system has many other gaps. The trial also focused on whether teens entered care, not on whether the care worked.
The MILESTONE results have already begun shaping mental health policy in some European countries. The next step is figuring out how to embed managed transition into routine practice without overwhelming clinicians, and to combine it with longer-term support so teens don't just attend the first adult appointment but stay engaged.