Art therapists are licensed therapists who focus on treating patients in the way the title implies. I don't think I'd call it science, although the one graduate program I'm familiar with has their students treat children and report on the efficacy of the results.
It's often an MA degree, so there's no pretense of it being a scientific endeavor.
I'm assuming that art therapy is grounded in a scientific understanding of psychotherapy. You don't need to be a professional scientific researcher to practice science.
I realize that my wording was ambiguous so I'm sorry for that.
It's often an MA degree, so there's no pretense of it being a scientific endeavor.