This study will determine the effectiveness of integrated behavior therapy in treating children with selective mutism.

Selective mutism (SM) is a childhood behavior disorder that interferes with social and educational development. It is characterized by a persistent failure to speak in specific social situations, despite being able to speak in other situations. Children with SM typically speak when they are at home with immediate family, but fail to speak in other settings. Behavior therapy (BT), commonly used for treating anxiety disorders and phobias, is a type of treatment that uses training and desensitization methods to help patients become more comfortable in situations that cause anxiety. Based on available evidence, integrated BT, which involves parents, teachers, and the therapist, may be an effective treatment for SM. This study will determine the effectiveness of integrated BT in treating children with selective mutism.

Following a diagnostic assessment to determine eligibility, participants in this single-blind study will be randomly assigned to receive BT either immediately upon study entry or after a 3-month waiting period. BT will consist of 20 1-hour treatment sessions over 6 months. In BT, children will practice speaking to people with whom it has been difficult to speak in the past. Parents, teachers, and children will be taught about anxiety related to SM, setting treatment goals, monitoring anxiety, learning skills to relax, and gradually entering situations that may trigger anxiety. These skills will be practiced during treatment sessions, in school with other children and teachers, and at home on a daily basis. Both parents and teachers will record activities that children have been able to accomplish. In addition, participants will attend study visits at Weeks 8, 12, and 24 for assessments of outcomes.

Participants who are assigned to the waitlist group will not receive treatment during their first 3 months in the study. They will attend study visits at Weeks 8 and 12 to assess any improvement in symptoms. Participants whose symptoms do not improve by the end of the 3-month period may either stop participation or receive 6 months of BT.

All participants will attend one 2- to 3-hour follow-up visit 3 months post-treatment. This visit will include interviews and questionnaires about SM symptoms.

Inclusion Criteria:

• Diagnosis of selective mutism
• Score of less than 60 on the Childrens Global Assessment Scale (CGAS)
• Has lived continuously with a primary caretaker who has known the child well for at least 6 months prior to study entry and is legally able to sign the consent form

Exclusion Criteria:

• Diagnosis of any of the following psychiatric disorders: bipolar disorder, pervasive developmental disorder (e.g., Asperger's, autism), mental retardation, or psychotic disorder
• Possibility that a communication disorder may account for the selective mutism
• Current use of or a clinical indication for use of psychotropic medication (youth entering study on a stable psychostimulant regimen for ADHD will not be excluded)
• History of unsuccessful treatment with cognitive behavioral therapy for anxiety that occurred within 2 years prior to study entry
• Any major neurological disorder or major medical illness that may prevent study participation
• Child and/or parent is not English-speaking and is unable to complete measures or treatment without the assistance of a dedicated translator
• Child is not currently attending school (including pre-school), day camp, or other structured daily activity, or has missed more than 50% of school days in the 2 months prior to study entry
• Child's primary teacher is unwilling or unable to participate in the treatment plan