Forty children with CAS, between 2;5 and 7;11 years of age will receive DTTC treatment 2x/week over an 8-week period along with home practice with a caregiver. Prior to treatment, all caregivers will complete an online self-guided educational module about CAS and DTTC. Participants will be randomized to one of two groups: 1) Direct Training Group (DTTC + Home Practice + Direct Caregiver Training); 2) Indirect Training Group (DTTC + Home Practice + Indirect Caregiver Training).
Children in the Direct Training Group will receive DTTC treatment during one half of each session administered only by the SLP, while the caregiver observes. DTTC will be administered by the caregiver with direct coaching by the speech language pathologist (SLP) in the other half of the session. Children in the Indirect Training Group will only receive DTTC treatment administered by the SLP, while the caregiver observes. In both groups, caregivers will review home practice guidelines with the clinician at the end of each therapy session, and engage in home practice with their children. Home practice will consist of 30-minute practice sessions 3x/week during the 8-week treatment phase and 6x/week during the 4-week follow-up phase. Caregivers in the Direct Training Group will be provided specific guidance regarding practice techniques, whereas caregivers in the Indirect Training Group will only be provided treatment words to be practiced at home and instructed to apply what they have observed during SLP-administered DTTC.
Probe data will be collected during the Pre-Treatment, Treatment and Follow-Up phases. The study duration is 16 weeks in total duration, for all participants. Probe words will consist of 20 potential treated items to evaluate treatment gains and 30 generalization items to assess carryover of treatment gains to untreated words.
The study will address the following aims:
Aim 1: Quantify the effects of direct vs. indirect caregiver training during a period of DTTC combined with home practice on whole word accuracy in treated and generalization probes at post-treatment and maintenance.
Aim 2: Quantify the effects of direct vs. indirect caregiver training during a period of DTTC combined with home practice on phoneme accuracy in treated words and generalization probes at post-treatment and maintenance.
Aim 3: Quantify the effects of direct vs. indirect caregiver training during a period of DTTC combined with home practice on speech intelligibility at post-treatment and maintenance.
Aim 4: Quantify the effects of direct vs. indirect caregiver training during a period of DTTC combined with home practice on functional communication at post-treatment and maintenance.