Effectiveness and cost-effectiveness of high-intensity versus low-intensity speech intervention in children with a...

In children with a cleft palate with or without a cleft lip (CP±L), some evidence exists for superior results of high-intensity speech intervention (HISI) compared with low-intensity speech intervention (LISI) on speech and health-related quality of life (HRQoL). However, the existing research often involves small sample sizes. Additionally, therapy in these studies is typically administered by researchers with extensive experience in treating speech disorders in these children. In contrast, first-line speech-language pathologists (SLPs) often possess considerably less experience in treating these children and clinical practice is subject to a wider array of environmental influences. Moreover, there are insufficient data on the cost-effectiveness of HISI compared with LISI. So far, these factors have hampered the implementation of HISI in clinical cleft practice.

The purpose of this study is twofold: (1) to compare the effectiveness of HISI and LISI on a larger societal scale, as delivered by first-line SLPs, on speech and HRQoL in Belgian Dutch-speaking children with a CP±L; and (2) to evaluate the cost-effectiveness.

This study consists of a large-scale, longitudinal, two-centre randomized controlled trial to investigate the effectiveness of HISI and LISI. Children with a CP±L, aged between 4 and 12 years, are randomly assigned to one of the two intervention groups. A sample size calculation determined that 35 participants per group are needed to ensure adequate statistical power. Children in the HISI group will receive intervention with a session duration of 30 min, a dose frequency of five sessions per week and a total intervention duration of 8 weeks (two 4-week blocks with a rest period of 12 weeks). Children in the LISI group will receive intervention with a session duration of 30 min, a dose frequency of two sessions per week and a total intervention duration of 20 weeks. The cumulative intervention intensity is kept constant. Each child will receive identical phonetic-phonological speech intervention provided by first-line community SLPs in private practices. Speech samples and patient- and caregiver-reported outcome measures will be collected on multiple data points before, during and after the intervention period. The cost-effectiveness will be evaluated by applying a cost-effectiveness and cost-utility analysis.

It is hypothesized that HISI will lead to superior speech outcomes in terms of consonant production and proficiency, resonance, speech understandability and speech acceptability, as well as improved HRQoL compared with LISI. Additionally, HISI is expected to be cost-effective compared with LISI.

This project contributes to the development of evidence-based clinical practice guidelines regarding speech intervention intensity in children with a CP±L.

What is already known on the subject Speech intervention for children with a CP±L is traditionally provided once or twice per week for 30 min for months or years by first-line community SLPs in private practices or rehabilitation services. However, scientific evidence supporting the effectiveness of this rather low intervention intensity is limited. In recent decades, the focus has shifted to HISI, in which intervention sessions are concentrated within a short period of time, as a more promising intervention intensity. Several studies regarding HISI have shown promising results on speech and HRQoL in children with a CP±L compared with LISI. Clustering sessions also have the potential to be more cost-effective than LISI since fewer sessions are required to achieve the same outcomes, thus reducing the financial burden. However, comprehensive evaluations of cost-effectiveness are lacking. Therefore, before HISI can be implemented in clinical practice, more evidence is needed regarding its effectiveness and cost-effectiveness compared with LISI. What this paper adds to the existing knowledge The current project will compare the effectiveness of HISI and LISI in Belgian Dutch-speaking children with a CP±L aged between 4 and 12 years old. For this purpose, a large-scale randomized controlled trial will be performed. Primary outcome measures will include perceptual assessments of speech, while secondary outcome measures will assess multiple dimensions related to HRQoL, such as difficulties with speaking, emotional well-being, perceptions and attitudes related to speech through various psychosocial outcome measures. Additionally, the cost-effectiveness of both intervention intensities will be compared. What are the potential or actual clinical implications of this work? Providing more evidence regarding HISI can facilitate the implementation of this intervention model in first-line cleft speech care. This project has the potential to offer a solution to prolonged speech intervention by achieving satisfactory results more quickly, which could significantly reduce the duration of intervention and the associated financial burden.