How the CReDDiS project, Scandcleft Trials, and TOPS study are shaping evidence-based assessment and treatment for cleft-related speech disorders.
About 1 in 700 children are born with cleft lip or palate, and up to 50% of them will show speech or nasality problems by preschool age. For too long, SLPs faced these challenges without clear evidence to guide surgical timing or therapy selection. Major longitudinal studies, the Scandcleft trials and the ongoing TOPS study, are now linking specific surgical protocols to speech outcomes, while standardized assessment tools like SVANTE and CLISPI are giving clinicians a shared language to measure progress reliably.
These developments are not just academic; they are reshaping how SLPs assess and treat compensatory articulation, advocate for early repair, and structure telepractice services. Becoming a speech-language pathologist means preparing for precisely this kind of complexity, where a child's speech trajectory can be predicted and interrupted more effectively than ever before. For a broader look at the range of conditions SLPs navigate alongside cleft palate, the public health speech pathology career path offers useful context on population-level communication needs.
Recent longitudinal trials have reshaped how speech-language pathologists understand cleft palate speech disorders, underscoring that effective management hinges on early, precise assessment and a clear distinction between structurally-based and learned errors.
Children with cleft palate can present with a range of speech and language disorder symptoms that SLPs need to recognize quickly:
After palate repair, a persistent gap between the soft palate and the back of the throat, known as velopharyngeal insufficiency (VPI), prevents the normal closure that separates the oral and nasal cavities during speech. This structural problem directly causes hypernasality, nasal emission, and can lead children to adopt compensatory motor patterns to build pressure for consonants. Without surgical or prosthetic management, these patterns become ingrained, making later therapy more challenging.
Otitis media with effusion (OME) occurs in virtually all children with cleft palate. The resulting fluctuating mild hearing loss interferes with the consistent auditory feedback children need to develop accurate speech models. Even temporary hearing dips can delay phonological and language development, compounding the effects of a cleft on communication. Routine OAE hearing test interpretation and audiologic management are therefore inseparable from speech therapy planning.
A foundational concept in cleft speech therapy is the difference between obligatory errors, those caused directly by structural anomalies like VPI, and compensatory errors, which are learned motor responses to the lack of oral pressure. Obligatory errors, such as hypernasality or nasal emission on pressure sounds, typically resolve only after surgical or prosthetic correction of the velopharyngeal gap. Compensatory errors, like glottal stops, persist even after structural repair and require direct speech therapy techniques to retrain placement and manner. Recognizing this distinction drives treatment sequencing: schedule for physical management first, then target maladaptive articulatory patterns through behavioral intervention.
The CReDDiS project (Cleft-Related Development Disorders in Speech/Language) is a long-term research program based at Karolinska Institutet's Division of Speech and Language Pathology. It zeroes in on how cleft palate affects speech and language development from infancy through school age, and it produces both outcome data and practical clinical tools that SLPs can use every day.
These studies aren't just distant academic exercises. The standardized assessment tools born from CReDDiS, such as SVANTE and CLISPI, are designed for adaptation across languages and cultures, reflecting the growing importance of global SLP research to everyday clinical practice. That means an SLP in Texas can apply the same framework as a colleague in Stockholm. Moreover, the surgical timing evidence from TOPS directly informs what you might expect when a child enters therapy, no matter where the surgery took place. When you know that up to half of children with cleft palate experience speech issues into preschool years, you can plan intervention strategies with greater confidence. For SLPs who want to understand how these communication challenges fit into the broader landscape of practice, a background in communication disorders degree careers provides helpful context for interpreting this kind of cross-national evidence.1
The cleft palate repair an infant receives is not a single surgery but a sequence of decisions, and the choice of surgical protocol and timing can create very different speech trajectories.
At the five-year mark, the Scandcleft trials revealed notable variation in speech depending on the surgical technique. Across the three randomised trial arms, the proportion of children with velopharyngeal competence ranged from 35% to 61%, meaning a significant number were already showing signs of velopharyngeal insufficiency (VPI).1 Rates of hypernasality followed a similar pattern; only 34% to 54% of children exhibited no hypernasality at this age.1 Consonant production, measured as percent consonants correct, averaged 86% to 92%, but acceptable consonant proficiency, a stricter measure, was achieved by just 27% to 73% of children.2 Even at this early stage, the pressure for secondary pharyngeal surgery had begun to mount, with rates varying substantially between treatment centres. Only about one in four children (23%) demonstrated speech proficiency on par with typically developing peers.3
By age 10, follow-up assessments led by Christina Persson showed some convergence. Peer-level speech proficiency had climbed to 56%, and velopharyngeal competence rates now spanned 62% to 94%, indicating improvement for many.4 However, the need for secondary surgery persisted, with 10% to 43% of children across centres having undergone a pharyngeal procedure by this point.4 The early differences between surgical groups had not completely resolved, and a sizeable minority still faced resonance and articulation challenges that impacted intelligibility and social participation. SLPs working with school-age children should note that types of lisps and consonant errors can share surface features with cleft-related articulation differences, making differential assessment essential.
In contrast to the Scandcleft trials' protocol comparisons, the TOPS trial directly addresses the question of timing: is palate closure at 6 months, rather than 12 months, more beneficial for speech? The primary outcome is perceived velopharyngeal function at age 5.5 As of 2025-2026, no peer-reviewed five-year speech outcomes have been published, though the trial's 550 infants from five countries have been enrolled and followed.5 Preliminary findings are eagerly awaited, as they will provide the most direct evidence yet on whether early closure reduces VPI and the burden of later therapy.
The Scandcleft results underscore that no surgical protocol guarantees normal speech development. Even with optimal repair, a large percentage of children will need speech therapy to address compensatory articulation errors, hypernasality, or weak consonant pressure. SLPs can expect to see cleft palate on their SLP caseloads across school and medical settings well into the school years. Early referral for assessment and therapy, coupled with standardised tools like SVANTE, becomes essential for monitoring progress and planning interventions. The data also highlight the importance of interprofessional collaboration: the SLP's role in flagging persistent VPI and recommending further surgical evaluation is critical to achieving long-term speech competence.
Cleft lip and palate conditions are among the most common congenital anomalies, with far-reaching implications for speech development. Ongoing trials like Scandcleft and TOPS are shaping our understanding of surgical timing and speech outcomes.
Standardized speech assessment tools transform how SLPs evaluate cleft palate speech by enabling consistent, comparable measurements across clinics and research studies. Without a common framework, describing articulation errors and nasality can become subjective, making it difficult to track progress or compare outcomes between centers. The tools developed by the CReDDiS group at Karolinska Institutet directly address this challenge, offering rigorous methods that balance research precision with clinical feasibility.
SVANTE, the Swedish Articulation and Nasality Test, provides a comprehensive evaluation of speech signs related to articulation and nasality.1 It uses single-word, sentence, and connected speech tasks to capture real-world performance, and it scores both percent consonants correct and ordinal ratings of error types.2 Errors are classified as oral or non-oral, which helps pinpoint whether a child is using compensatory misarticulations or true velopharyngeal insufficiency. Normative data come from 443 participants aged 3 to 19 years, so clinicians can compare a child's performance to age- and dialect-matched peers.3 SVANTE has been validated in Swedish and Norwegian, and its component-level transcription approach differs from frameworks like CAPS-A (Americleft), making it especially useful when detailed phonetic analysis is needed.1
CLISPI (Cleft Lip and Palate Speech Indicators) is a restricted-word framework designed for cross-center and cross-linguistic outcome studies.4 Where SVANTE dives deep into a single language's norms, CLISPI focuses on a small set of carefully chosen words that elicit key cleft speech features regardless of the child's native language. This standardization allows international trials like Scandcleft to compare speech outcomes directly. SLPs interested in standardized language assessments will find CLISPI accessible by contacting the CReDDiS group at Karolinska Institutet.
Tools like SVANTE and CLISPI reduce inter-rater variability and give SLPs a shared vocabulary for describing cleft speech characteristics. In multicenter research, this consistency is essential for drawing meaningful conclusions about surgical timing or therapy effectiveness. For everyday clinical work, using a structured protocol ensures that no subtle signs, such as mild nasal emission or glottal stops, are overlooked. The CReDDiS group also maintains related instruments like PUMA and RENAS, further expanding the toolkit for specific research questions.4
SVANTE materials and scoring guides are available through Karolinska Institutet and associated publications. For US clinicians, alternatives like the Pittsburgh Weighted Speech Score and Americleft consensus parameters offer similar standardization, though they may emphasize different scoring philosophies. Blending these approaches, for instance using SVANTE-inspired phonetic transcription alongside the Pittsburgh scale, can enrich clinical documentation and align with international evidence. SLPs who work with children from diverse linguistic backgrounds may also find bilingual SLP materials a useful complement to these assessment frameworks.
When addressing cleft palate speech errors, SLPs must distinguish between obligatory errors, which resolve with surgical management of velopharyngeal insufficiency (VPI), and compensatory articulation errors, which require direct speech therapy to unlearn maladaptive patterns like glottal stops and pharyngeal fricatives. This fundamental distinction guides the entire treatment plan.
Obligatory errors stem from structural deficits, such as an inability to build oral pressure due to VPI. These errors, including nasal air emission and weak pressure consonants, are not volitional and typically resolve after successful surgical repair. In contrast, compensatory articulation errors are learned behaviors that develop as a child attempts to produce sounds despite velopharyngeal incompetence. Because these patterns persist even after anatomy is corrected, they demand direct intervention to retrain oral placement and airflow.
Effective intervention follows a systematic hierarchy that mirrors motor learning principles. Therapy typically begins with establishing correct oral airflow and placement, often using simple plosives or fricatives. Once the child can produce a sound accurately in isolation, the SLP moves to syllables and words, then phrases and connected speech. This progression ensures a solid foundation at each level before advancing, reducing frustration and promoting carryover. SLPs working with children on the autism spectrum or with other co-occurring disorders may recognize this same hierarchical structure from autism speech therapy techniques used to build communication skills step by step.
Therapy intensity and total dose vary widely, but evidence-based benchmarks have emerged. A 2021 study by Alighieri and colleagues compared two blocks of 10 total clinician hours: a high-intensity model (5 sessions per week for 2 weeks) and a low-intensity model (1 session per week for 10 weeks).1 Both delivered equivalent total hours, but the high-intensity block may accelerate progress for some children. Other protocols include the SonoSpeech pilot program, which used 6 weekly 45-minute sessions with a minimum of 100 correct productions per session,2 and Pamplona et al.'s programs: a standard approach of 2 weekly 45-minute sessions over 9 months, or an intensive summer camp with 4-hour daily sessions for 3 weeks.3 The Smile Train guidelines recommend 3 sessions per week with at least 1 hour of SLP contact weekly.4 Underlying these schedules is a motor learning consensus: aim for 60, 120 correct productions per session to drive neural change.2
Instruments like nasometry and electropalatography (EPG) add a visual dimension to therapy, helping children understand and adjust velopharyngeal function and tongue placement. Nasometry measures nasal resonance during speech, providing real-time feedback that can reduce hypernasality. EPG displays tongue-to-palate contact patterns, enabling precise correction of articulatory placement. When combined with traditional hierarchical therapy, these tools can boost motivation and outcomes, especially for children who struggle to perceive their own errors. For SLPs seeking to expand their toolkit, best speech therapy apps offer supplementary practice options that can extend session gains into the home environment.
Identifying speech difficulties in children with cleft palate begins within the first year of life, ideally before the palate is repaired. Early SLP involvement includes parent counseling on feeding and communication development, monitoring pre-linguistic vocalizations, and establishing a baseline assessment before surgery. This proactive approach sets the stage for timely intervention and reduces the risk of long-term communication disorders.
Before palate repair, the SLP coaches families on non-nutritive sucking, oral stimulation, and sound play. Around 6 months, watch for a rich inventory of babble sounds; after repair (often at 10, 14 months), the child should rapidly add pressure consonants. By 12 months, first words should emerge, and any nasal air loss or compensatory errors warrant immediate attention. At 18 months, a full range of consonants is expected, and by 3 years, speech should be intelligible to unfamiliar listeners. At 5 years, residual articulation errors or mild hypernasality still require monitoring, even if the child has been discharged from regular surgical follow-up. Families who need guidance on early communication targets may also find late talker activities for parents a useful supplement to clinic-based counseling.
Telepractice has emerged as a feasible and acceptable model for cleft speech therapy.1 Three systematic reviews published in 2024 examined its effectiveness across a combined pool of 11, 23, and 11 primary studies respectively, confirming that remote assessment of articulation shows moderate-to-high agreement with in-person evaluation, though resonance judgments remain weak when done virtually.1 Treatment delivered via telepractice can boost percent consonants correct (PCC) by 15, 30%,2 with parent coaching approaches yielding consistent within-group improvements in PCC and reduced compensatory errors.1 Technical recommendations include secure, low-bandwidth platforms, acoustic optimization, and thorough caregiver training.2 High caregiver satisfaction is reported, but engagement remains a critical determinant of success.1 SLPs looking to build out a remote service model can consult our SLP telepractice step-by-step guide for practical setup advice.
Many families live far from craniofacial centers, making telepractice a powerful tool for reducing disparities. The recommended model is hybrid: use telepractice for articulation therapy and parent coaching, while reserving in-person visits for complex resonance assessment and nasometry.1 The Gantz Foundation's structured early stimulation protocol, which combines educational content, interactive videos, and standardized evaluation templates, showed significant reductions in compensatory articulation (p < 0.001) when delivered remotely; notably, 84% of children presented with severe compensatory articulation at program onset.3 A Thailand-based study reported mean PCC gains of 9.4 points at the word level and 13.3 points at the sentence level through teledelivered therapy.4 Research on Persian-speaking children further supports intensive hybrid formats, with gains in PCC and decreases in hypernasality and nasal emission across treatment periods as long as 75 weeks.5 Telepractice is not a compromise; it is an evidence-based expansion of the SLP's toolkit.
Cleft palate speech disorders require specialized knowledge that many SLP graduate programs cover only briefly. To prepare clinicians who can effectively serve this population, programs must include targeted coursework and clinical experiences.
Foundational training starts with the anatomy of the velopharyngeal mechanism, the soft palate and pharyngeal walls that control resonance. Students need repeated practice in perceptual assessment, learning to distinguish hypernasality, hyponasality, and nasal emission by ear. Equally important is recognizing compensatory articulations (such as glottal stops and pharyngeal fricatives), which can persist even after palate repair. Programs should teach clear decision points: when to refer for instrumental assessment like nasometry or videofluoroscopy, and when to flag a child for possible secondary surgical management. Understanding where cleft palate fits within the broader SLP scope of practice helps students contextualize these skills within their overall clinical training.
On a cleft and craniofacial team, the SLP is one voice among many. Surgeons, orthodontists, ENT physicians, psychologists, and audiologists all contribute to the child's care. This collaboration shapes the SLP's clinical role: surgical timing and technique influence speech outcomes, and the SLP's perceptual ratings often guide surgical decisions. Regular team meetings ensure that therapy goals align with the broader treatment timeline, and that speech concerns, like persistent velopharyngeal insufficiency, are addressed without delay. Students considering this specialty path can explore SLP additional certifications that build on core graduate training.
Not every SLP will work on a cleft team, but many will encounter a child with a history of cleft palate in schools or SLP private practice. These clinicians do not need to become cleft specialists, but they do need enough baseline knowledge to provide appropriate direct therapy for residual articulation errors and to recognize when progress stalls. Most importantly, generalists must know when to consult or refer back to a cleft team for a resonance evaluation or instrumental assessment. Building that referral pathway protects the child from years of ineffective therapy.
Earlier Scandcleft phases tracked speech at preschool and early school ages; now investigators are looking further down the road.
The next wave of Scandcleft data will come from Christina Havstam's ongoing assessment of speech outcomes in 9-year-olds (2024-2027). By this age, children have typically mastered connected speech, but complex sound combinations and higher linguistic demands can expose lingering velopharyngeal gaps or compensatory errors that were harder to detect at age 5. This phase asks whether early surgery gains hold as children engage in independent reading, classroom discussions, and peer conversations. It also probes the stability of nasalance scores and articulation accuracy over time, information that could refine long-term surgical and therapeutic recommendations.
Cleft speech assessment has historically been developed and validated within majority languages, but clinicians increasingly serve bilingual families. Researchers are now examining how cleft-related speech patterns manifest across different phonetic inventories, tonal languages, and dialectal variations. Tools like SVANTE and CLISPI are being tested for adaptation, and new normative data sets are emerging for languages beyond English and Swedish. This work is especially relevant for bilingual speech pathologists, as it aims to reduce misdiagnosis in multilingual children and ensure that therapy targets are linguistically appropriate.
Beyond traditional perceptual ratings, technology is opening new avenues for assessment and treatment. Instrumental biofeedback such as nasometry gives clients real-time visual feedback on nasal airflow during speech. Ultrasound tongue imaging lets both therapist and child see tongue placement for challenging sounds like /s/ and /ʃ/, aiding in the correction of compensatory articulation. Meanwhile, AI tools for speech-language pathologists are being trained to analyze speech recordings for hypernasality and audible nasal emission, potentially offering objective, scalable screening in telepractice and low-resource settings.
As the Scandcleft 9-year results and the TOPS trial findings are published over the next few years, the evidence base for cleft palate speech therapy will shift. SLPs who stay current with these international studies can bring the most up-to-date protocols to their clients. We will continue to cover the clinical implications of this research, so consider this article a living resource and check back for updates as new data emerge.
Families and clinicians often have pressing questions about cleft palate speech disorders. Below are evidence-based answers to common queries, informed by international research and standardized assessment tools.
