The goal of this randomized-controlled trial is to compare distributed treatment schedules and intensive treatment schedules in 84 school-age children with residual speech sound disorders. The main question it aims to answer is:

• How does intensive and distributed treatment affect speech sound learning in residual speech sound disorder?

Some participants will be treated with a traditional Distributed schedule of 2 sessions per weeks for 8 weeks (16 hours total), whereas others will be treated with an Intensive schedule and will complete 16 hours of treatment in 4 weeks.

Residual speech sound disorders are defined as speech sound disorders that persist past ~8-9 years and may lead to social, academic, and vocational limitations. Thus, there is a need to investigate how treatment schedules affect speech sound learning. The overall objective of this study is to optimize a suite of theoretically motivated, high-fidelity, motor-based treatments delivered at the appropriate intensity, despite practical barriers, for the most commonly impacted RSSD sounds: /ɹ, s/. Our central working hypothesis, supported by our preliminary work, is that Speech Motor Chaining is more efficacious when delivered intensively (i.e., closely spaced for a fixed number of sessions). The theoretical rationale is that increasing intensity early in treatment will mitigate erred practice between sessions, improving outcomes relative to more customary practice distributions. To test this hypothesis, children will be randomly assigned to receive a standard Distributed treatment schedule or an Intensive treatment schedule.

Inclusion Criteria:

• Must speak American English as a dominant language.
• Must have began learning English by at least the age of 3 years.
• Must be between 9;0 to 17;11 years of age.
• Must have reported difficulty with /ɹ/ and/or /s/ production
• Must pass pure tone hearing screening at 25 dB at 1000, 2000, and 4000 Hz.
• Must receive a scaled score of at least 5 on the Listening Comprehension and Story Retelling subtests of the Test of Integrated Language and Literacy Skills (TILLS)
• Must receive a percentile score of 5 or below on the Goldman-Fristoe Test of Articulation-3 (GFTA-3) Sounds in Words subtest.
• Must have 1 scorable response with 5+ consecutive correct /pataka/ with > 3.4 syllables per second in the MRR-Tri task of the Maximum Performance Tasks OR must demonstrate no childhood apraxia of speech (CAS-only) features in BOTH articulatory and rate/prosody domains of the ProCAD.
• Must score <40% accurate on /ɹ/ and/or /s/ probes assessing these sounds at the word level.
• Must express a desire to modify their speech.

Exclusion Criteria:

• Must have no known history of autism spectrum disorder, Down Syndrome, cerebral palsy, intellectual disability, permanent hearing loss, or brain injury.
• Must not have current cleft palate or voice disorder.

All perceptual ratings will be obtained from raters who are blinded to treatment group and to timepoint. Binary rating responses will be obtained from three listeners per token.