Box 1.

—General selection criteria

• Newly referred singleton children acquiring English in a monolingual home

• Aged under 3½ years at initial attendance for speech and language therapy assessment

• No diagnosis of severe learning difficulties or autism

• No oromotor deficits

• No primary diagnosis of dysfluency (stammering) or dysphonia (voice disorders)

• No siblings currently receiving speech and language therapy

• Children had to satisfy one of the clinical criteria (box B2)

• Be considered to have significant clinical difficulties by the speech and language therapist

• A “carer” had to attend sessions

• Parents had to give consent