The behavioral treatment, which involved parents heavily and is already known to work for older kids and teens, left almost three quarters of the young children significantly better off, according to objective measurements.
"I really think that the results highlight this family-based cognitive behavior therapy model as the first-line treatment for children with OCD," Jennifer Freeman, the study's lead author, told Reuters Health.
Freeman is affiliated with the Alpert Medical School of Brown University, the Pediatric Anxiety Research Clinic at Rhode Island Hospital and the Intensive Program for Obsessive-Compulsive Disorder at Bradley Hospital in Providence, Rhode Island.
People with OCD have a set of compulsions - feeling compelled to do something - that cause them distress or disrupt their daily lives. For example, a person may have an intense fear that something bad will happen unless they perform a certain action multiple times.
The condition has been found to run in families, according to the U.S. National Institutes of Health (NIH), but its cause is still unclear.
About 2.2 million U.S. adults are affected by OCD, with approximately one-third of those having developed symptoms as children, according to NIH.
Considerable research has shown that CBT alone or in combination with anti-anxiety medicine is effective in treating OCD among older children and adolescents, Freeman and her colleagues write in JAMA Psychiatry.
There was little evidence about what worked for younger children with OCD, however.
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