Introduction

The term ‘elective mutism’ was originally coined in 1934 by the Swiss pioneer of child psychiatry, Moritz Tramer. However, it is assumed that the German physician, Kussmaul, was the first to describe three cases in 1877 under the term ‘aphasia voluntaria’. Whereas the ICD-10 stuck to the original term ‘elective mutism’, the DSM-IV has slightly changed the term to ‘selective mutism’. Both the original designation and the fact that the ICD-10 as the dominant European scheme of classification uses ‘elective mutism’ as the descriptor are the reasons why this chapter follows this term.

Children with elective mutism are rarely seen in clinical practice, although it may be assumed that there are some more in the general population who will either be referred rather late or perhaps never for assessment and intervention. Consequently, a large body of clinical knowledge rests on case reports or descriptions of small series of children with a few exceptions of studies based on more extended series of patients.

Definition and classification

According to the ICD-10, the following four criteria lead to the diagnosis of elective mutism:

• marked and consistent selectivity in speaking, i.e. failure to speak in social situations

• a normal or near-normal level of language comprehension

• a level of competence in language expression that would be sufficient for social communications, and

• demonstrable evidence that the child could and did speak normally or almost normally in some situations.