The importance of production frequency in therapy for childhood apraxia of speech.

PURPOSE: This study explores the importance of production frequency during speech therapy to determine whether more practice of speech targets leads to increased performance within a treatment session, as well as to motor learning, in the form of generalization to untrained words.
METHOD: Two children with childhood apraxia of speech were treated with an alternating treatment AB design, with production frequency differing in the 2 treatments. The higher production frequency treatment required 100+ productions in 15 min, while the moderate-frequency treatment required 30-40 productions in the same time period. One child was treated 3 times weekly for 11 weeks; the other child was treated twice weekly for 5 weeks. At the conclusion of each treatment phase, 5 min of probes were administered to determine whether generalization had occurred. Maintenance data to measure performance and learning were collected after a break from treatment.
RESULTS: Both children showed improvement on all targets; however, the targets with the higher production frequency treatment were acquired faster, evidenced by better in-session performance and greater generalization to untrained probes.
CONCLUSIONS: Both treatment designs were effective, though frequent and intense practice of speech resulted in more rapid response to treatment in 2 children whose primary communication difficulty was childhood apraxia of speech.