Selective mutism (SM) is a relatively rare childhood disorder characterized by a consistent failure to speak in specific settings, such as school, despite speaking normally in other settings, such...Show moreSelective mutism (SM) is a relatively rare childhood disorder characterized by a consistent failure to speak in specific settings, such as school, despite speaking normally in other settings, such as at home. Little is known about the etiology of SM, although some studies show evidence of social anxiety or problems in communication skills as underlying mechanisms. This study investigated whether some children with SM in the Netherlands have more social anxiety and more problems in communication skills than peers. Moreover, it examined which of these factors has the strongest association with the non-speaking behaviour characteristic of SM. Parents of 28 children with SM (Nboys=6; Ngirls=22) and 44 children without SM (Nboys=19, Ngirls=23) aged 4-9 years completed questionnaires on their child's speaking behaviour (Selective Mutism Questionnaire), communication skills (Children's Communication Checklist) and social anxiety (Social Worries Anxiety Index for Young children). Results show that children with SM have significantly more social anxiety and more problems in communication skills than peers. Furthermore, more problems in non-speaking behaviour are significantly associated with more social anxiety and more problems in communication skills. Non-speaking behaviour has a stronger correlation with social anxiety than with communication skills. A hierarchical regression shows that social anxiety is a strong significant predictor (80%) of nonspeaking behaviour. Communication skills have minimal additional impact (0.5%) on the variance of non-speaking behaviour. Finally, communication skills partly (11%) explain why some children with social anxiety do not speak and other children do. A limitation of this study is the small sample size, which did not allow to control for ethnicity. Possibly this affects the outcomes of communication skills. Nevertheless, we feel confident that SM is mainly related to social anxiety. Communication skills have a small influence on the outcome of SM. Based on this we recommend that treatment of SM should mainly focus on social anxiety and in addition we should be alert for problems in communication skills.Show less