Definition & key features

• Persistent failure to speak in specific social situations where speaking is expected, lasting at least 1 month (not limited to first month of school).
• Interferes with educational, occupational or social communication and functioning.
• The child speaks in other situations (e.g., at home) and the disturbance is not due to lack of language knowledge or a communication disorder.
• Often associated with marked social anxiety and behavioural inhibition.

Prevalence & risk factors

• Selective mutism is uncommon—estimated prevalence ~0.3–1% in children—but may be under‑recognised.
• Typical onset in early childhood (preschool or early school years), often becomes noticeable when child starts school.
• Risk factors: behavioural inhibition, family history of anxiety, temperamental shyness, language delay, bilingualism (not causal), and overprotective parenting styles.

Clinical presentation

• Child is verbally communicative at home with parents but silent at school or with strangers.
• May use non‑verbal communication (gestures, nods) or whispering, but limited oral speech in targeted settings.
• Associated symptoms: social withdrawal, avoidance of eye contact, increased physiological arousal (trembling, blushing), and academic difficulties due to non‑participation.

Assessment checklist

1. Detailed developmental & language history: assess expressive language skills, bilingual context and hearing.
2. Contextual analysis: settings where child speaks vs is silent—home, preschool, clinic, with peers, with adults.
3. Assess severity and functional impact: academic performance, social relationships and family stress.
4. Screen for comorbidities: social anxiety disorder, separation anxiety, specific phobia, ASD and selective mutism can co‑occur.
5. Gather collateral from parents, teachers and caregivers; classroom observation is often essential.

Evidence‑based treatments

• Behavioural interventions: first‑line—shaping, stimulus fading, gradual exposure, positive reinforcement and contingency management.
• Stimulus fading: slowly introduce new people into the context where the child speaks (start with familiar adult, then add teacher) to increase speaking opportunities.
• Shaping & reinforced practice: reinforce successive approximations to speech (e.g., making a sound → single word → short phrase).
• School‑based interventions: collaborate with teachers to create low‑pressure speaking tasks, use peer models, and implement reward charts.
• CBT components: behavioural experiments, social skills training, anxiety management (relaxation, breathing), and graded exposures to feared speaking situations.
• Parent training: coaching parents to avoid speaking for the child, to use reinforcement, and to support gradual independence.
• Medication: SSRIs may be considered for severe cases or when significant comorbid social anxiety is present—typically adjunctive to behavioural therapy and under specialist supervision.

Practical intervention steps (school & clinic)

1. Build rapport in clinic—use play and non‑verbal interaction; avoid pressuring for speech early on.
2. Assess baseline speaking behaviours and set specific, measurable goals (e.g., child will answer a yes/no question to a teacher twice a week).
3. Implement shaping: reward small verbal behaviours and provide immediate positive reinforcement.
4. Use stimulus fading: begin with parent in classroom prompting, gradually replace parent with therapist/teacher and fade support.
5. Plan brief, frequent exposures in school (1–5 minutes) and provide teacher coaching and reinforcement strategies.

Practical tips for clinicians & teachers

• Start interventions early—addressing mutism in the first year of school yields better outcomes.
• Collaborate closely with teachers—provide simple scripts, reinforcement plans and regular brief check‑ins.
• Avoid pressuring the child to speak publicly; use choices and low‑demand tasks to elicit speech.
• Monitor language development and refer to speech & language therapy if concerns about expressive skills arise.

Key takeaways

• Selective Mutism is an anxiety disorder best treated with structured behavioural interventions in school and home settings.
• Stimulus fading, shaping, and reinforced practice are effective—early, collaborative, low‑pressure approaches work best.
• Refer for specialist assessment when language delay, neurodevelopmental disorder, or severe comorbidity are suspected; consider SSRI adjuncts for severe or refractory cases.