Treating Non-Oral Compensatory Misarticulations in Children With a Cleft Palate: A Randomized Controlled Trial on the Effect of Combined Phonetic-Phonological Intervention.

Purpose: This study compared the effects of motor-phonetic and combined phonetic-phonological intervention on the speech, health-related quality of life (HRQoL), and parent-reported intelligibility in Dutch-speaking children with cleft (lip and) palate (CP ± L) and non-oral compensatory misarticulations (CMAs).

Method: Fourteen children with CP ± L were randomly assigned to one of two interventions, that is, motor-phonetic intervention (n = 7, M_age = 7.39 years) or combined phonetic-phonological intervention (n = 7, M_age = 6.86 years) stratified by age and gender. Intervention was provided with a total duration of 1 week, a dose frequency of two sessions per day, and a session duration of 1 hr and targeted non-oral CMAs. Speech was assessed at different data points. HRQoL and intelligibility by different communication partners were assessed before and after the intervention using the VPI Effects on Life Outcomes questionnaire and the Intelligibility in Context Scale. Groups were compared over time using linear mixed models.

Results: Significant Time × Group effects were observed for "non-oral CMAs" and "Percentage Consonants Correct-Revised for word imitation and sentence imitation." These outcomes improved in both groups, but improvements were significantly larger in the combined intervention group. Similar effects were observed for holistic outcomes such as speech understandability and acceptability. In the group that received the combined intervention, improvements were maintained 3 months after the intervention period, whereas in the motor-phonetic group, the initial improvements were not sustained. HRQoL and intelligibility by the child's friends and acquaintances also improved in both groups, but improvements were higher in the combined intervention group.

Conclusions: This study demonstrates the superior effects of combined phonetic-phonological interventions over motor-phonetic interventions in eliminating non-oral CMAs. While motor-phonetic approaches tend to result in short-term gains, combined phonetic-phonological intervention strategies may lead to more long-lasting changes by promoting generalization. This underscores the importance of addressing both phonetic and phonological aspects of speech.