Characteristics of selective mutism in children include consistently not speaking in certain situations, extreme shyness, fear of social embarrassment, anxiety and social isolation, according to the American Speech-Language-Hearing Association. It is a rare disorder that affects only about 1 percent of the population.
For a definitive diagnosis of selective mutism, the period of not speaking must last more than a month and must not be associated with the child lacking knowledge or comfort, explains the American Speech-Language-Hearing Association. The lack of speaking must also interfere with school and cannot be associated with a communication disorder such as stuttering or a behavioral health issue such as autism.
A team is typically required to diagnose selective mutism, notes the American Speech-Language-Hearing Association. Most children are seen by a mental health professional, a pediatrician and a speech-language pathologist. The team reviews the child's academic history, screens his ability to hear, interviews the parents for possible behavioral health problems, evaluates speech and language, and conducts an oral-motor coordination examination.
Treatment for selective mutism depends on the underlying cause of the condition, adds the American Speech-Language-Hearing Association. Many times, the team employs a number of treatment options, including teachers to help the child at school, treating speech or language issues, and behavioral treatment.