Selective mutism — formative SAQs

SAQ 1 (10)

A 6-year-old girl is referred because her teacher reports she has "never heard her voice all year", yet her mother describes a cheerful chatterbox at home. The child speaks freely to one younger cousin but not to any adult outside the family. She hides behind her mother in clinic and produces no speech, though she nods and points. ^[14]

1. Define selective mutism using the DSM-5-TR framework and the setting-specificity principle. (3) ^{[14] [3]}
2. List the key differential diagnoses and the single mandatory investigation before settling on an anxiety diagnosis. (4) ^{[14] [11]}
3. Outline your initial assessment plan and the first-line management. (3) ^{[14] [5]}

Model answer

Definition. Selective mutism is a consistent failure to speak in specific social situations where speech is expected (such as school), despite speaking in other situations (such as home), present for at least one month (not limited to the first month of school), that interferes with educational or social communication and is not better explained by a communication disorder, lack of comfort with the spoken language, autism, schizophrenia or another psychotic disorder. The setting-specificity — fluent speech at home versus silence at school — is the diagnostic hook and reflects an anxiety-driven freeze rather than defiance. ^{[14] [3]}

Differentials and mandatory investigation. Normal shyness (resolves, no impairment); social anxiety disorder (the dominant comorbidity and conceptual relative); autism spectrum (communication deficit across ALL settings); hearing loss or glue ear (quiet in ALL settings); developmental language disorder; trauma or abuse (acute, context-bound silence); and a new-language comfort period in bilingual or migrant children. The single mandatory investigation is a hearing assessment — a child silent from undiagnosed hearing loss must never be labelled with an anxiety disorder. ^{[14] [11]}

Assessment plan and first-line management. Multi-informant history (child without pressure, parent about home speech, structured teacher report), map the speaking gradient across every setting, confirm hearing and spoken-language adequacy, and screen comorbidity and safeguarding. First-line management is psychoeducation (anxiety, not defiance) plus collaborative behavioural intervention — stimulus fading, shaping, positive reinforcement and defocused communication delivered with the school — with removal of pressure to speak. ^{[14] [5]}