It's no more confusing than saying "I am an adult psychologist" which could mean you are an adult and a psychologist or a psychologist who treats adults.
"Child and Adult Psychologist" also has 178k hits on Google that seems to have a similar usage. If it is commonly used like this in the industry, then I don't think it needs changing. Especially as you would have to change any other instances of "adult psychologist" to "adult-psychologist", which seems strange to me.
I think it would only cause confusion if the author was actually a child who is an adult psychologist, but then you probably wouldn't word it like this, anyway.
As for ways to get around this minor ambiguity, many other users have already given sufficient examples.