Evaluating the Results of Physician and Parent Decisions to Treat Selective Mutism With Fluoxetine

The Department of Counseling, Educational Psychology, and Special Education and the Department of Psychiatry at Michigan State University have coordinated efforts to provide a diagnostic and treatment investigation for children, ages seven to eighteen, with Selective Mutism. The purpose of this study is to examine the utility of fluoxetine for the treatment of this debilitating disorder. Fluoxetine is expected to improve social anxiety and selective mutism symptomology.

Children with selective mutism (SM) are at risk for current and continuing academic and socio-emotional difficulties. Unfortunately, this issue is complicated by the fact these children often respond poorly to psychosocial intervention. This leaves parents with the overwhelming decision to attempt a trial of medication regardless of the little available data on the evidence base of this approach. Despite the paucity of research, psychiatrists are prescribing fluoxetine for children with SM "off label", as the Food and Drug Administration (FDA) has yet to approve fluoxetine for this indication. This study blends the psychopharmacological expertise of psychiatrists with the mental health, systems, and psychological evaluation expertise of school psychologists to identify an appropriate psychopharmacological solution for children and adolescents with this debilitating disorder. To that end, this study will examine the utility of fluoxetine for the treatment of five children and adolescents, ages seven to eighteen, diagnosed with SM through the use of a non-concurrent multiple-baseline single-case design with a single-blind placebo-controlled procedure. Treatment effectiveness will be evaluated by visual analysis of the data, the Wampold and Worsham multiple-baseline design randomization test, and the Kendall's Tau + Mann-Whitney U effect size. Multiple methods of assessment including standardized measures, such as the Selective Mutism Questionnaire (SMQ), and behavior ratings, such as Direct Behavior Ratings (DBRs), will be used to gather baseline and treatment data. Multiple informants (i.e., parents, teachers, and psychiatrists) will provide information on treatment effect across settings (i.e., school and community). Information regarding adverse effects associated with fluoxetine treatment including a measure of behavioral disinhibition, parental acceptance of the fluoxetine intervention, and compliance with taking the medication will also be gathered.