The impact of age on the treatment of late-acquired sounds in children with speech sound disorders.

The question of 'when' to treat speech sounds is often posed in the context of normative data. The new normative data suggest that speech sounds such as /ɹ/ and /l/ are acquired earlier than previously thought. The present study compared the treatment of late-acquired sounds between two age groups of English-speaking children: Young children (4-5) and Old children (7-8). Eight monolingual children with speech sound disorder (SSD) participated in the study. Each child received a criterion-based, standardised, two-phase therapy protocol. Treatment efficacy was measured by examining children's accuracy on real world speech probes. Treatment efficiency was measured by calculating the number of sessions required to meet the exit criterion and the mean session duration. For treatment efficacy, young children learned treated sounds as effectively as oldchildren did. For treatment efficiency, both groups required a comparable number of sessions, but young children required longer sessions than old children. The results suggest that delaying treatment of individual speech sounds is unnecessary and that a range of sounds should be considered as potential treatment targets.