Brief Report CHARACTERIZING SELECTIVE MUTISM: IS IT MORE THAN SOCIAL ANXIETY? Katharina Manassis, M.D., 1,2n Daniel Fung, M.D., 4 Rosemary Tannock, Ph.D., 3 Leon Sloman, M.D., 5 Lisa Fiksenbaum, M.A., 3 and Alison McInnes, Ph.D. 3 Selective mutism (SM) occurs when a child persistently lacks speech in some social situations but not in others, despite the ability to use and comprehend language. While considered to be related to anxiety, SM is poorly understood and studies of SM children are often based on parent reports. This study developed a unique, non-verbally based assessment protocol for SM children in order to better characterize their clinical profile, language abilities, and learning abilities. A comparison was done with a group of children of similar age, with social phobia (SP) but no SM, to search for characteristics that might distinguish SM from other anxiety disorders. Twenty-three children partici- pated in the study (14 SM and 9 SP). The assessment protocol included standardized anxiety rating scales, cognitive and academic tests, and a speech and language assessment. SM and SP groups showed similar levels of anxiety and academic ability, but the SM group showed some language impairments relative to the SP group. Though requiring replication with a larger sample and nonclinical comparison group, the results suggest that SM children can be assessed by non-verbal means and that their disorder is characterized by anxiety and subtle language impairments. Depression and Anxiety 18:153–161, 2003. & 2003 Wiley-Liss, Inc. Key words: anxiety; selective mutism; language assessment; cognition INRODUCTION Selective Mutism (SM) occurs when a child persis- tently lacks speech in some social situations but not in others, despite the ability to use and comprehend language [APA, 1994]. Until recently, it was considered rare but often difficult to treat and was associated with high academic and social impairment [Bergman et al., 2002; Kolvin and Fundudis, 1981; Steinhausen and Juzi, 1996]. Two theoretical accounts have been proposed to explain SM: 1) speech restriction due to anxiety, especially extreme social anxiety, and 2) speech restriction related to language impairment or broader developmental delays. Recent studies have focused on the contribution of anxiety to the etiology of SM [Dummit et al., 1997; Kristiensen, 2000]. Many authors have also noted, however, that these children often have speech delay or speech difficulties, based on parent reports [Kolvin and Fundudis, 1981; Wilkins, 1985; Steinhausen and Juzi, 1996]. There have been no published reports of systematic evaluations of learning and language abilities in SM children themselves. This gap in the literature may relate to the challenges of testing these children. The aims of this study were 1) to DEPRESSION AND ANXIETY 18:153–161 (2003) 1 Hospital for Sick Children, Toronto, Ontario, Canada 2 Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada 3 Brain and Behavior Research Program, Hospital for Sick Children, Toronto, Ontario, Canada 4 Department of Child and Adolescent Psychiatry, Institute of Mental Health, Singapore 5 Centre for Addiction and Mental Health, Toronto, Ontario, Canada n Correspondence to: Dr. Katharina Manassis, Department of Psychiatry, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, M5G 1X8, Canada. E-mail: katharina.manassis@sickkids.ca Received for publication 15 December 2002; Accepted 25 June 2003 DOI: 10.1002/da.10125 Published online in Wiley InterScience (www.interscience.wiley. com). & & 2003 WILEY-LISS, INC.