Speech input processing in children born with cleft palate: A systematic literature review with narrative synthesis

Considering the role of speech processing in cleft-related speech sound disorders: Implications for causal pathways and classification systems

BACKGROUND

Classification systems in healthcare support shared understanding of conditions for clinical communication, service monitoring and development, and research. Children born with cleft palate with or without cleft lip (CP+/-L) are at high risk of developing cleft-related speech sound disorder (SSD). The way cleft-related SSD is represented and described in SSD classification systems varies. Reflecting on the potential causal pathways for different cleft-related speech features, including the role of speech processing skills, may inform how cleft-related SSD is represented in classification systems.

AIM & APPROACH

To explore and reflect on how cleft-related SSD is represented in current SSD classification systems in the context of considering how speech processing skills and other factors may be involved in causal pathways of cleft speech characteristics (CSCs).

MAIN CONTRIBUTION

Variation in the representation of cleft-related SSD in classification systems is described. Potential causal pathways for passive cleft- related speech features and different active CSCs are explored. The factors involved in the development and/or persistence of different active CSCs may vary. Some factors may be specific to children born with CP+/-L, but if speech processing skills are also involved, this is an overlap with other SSD subtypes. Current evidence regarding relationships between different speech processing skills and active CSCs is limited. Implications for the representation of cleft-related SSD in SSD classification systems are discussed.

CONCLUSION

There are different categories of cleft-related speech features which are essential to understand and identify in children with cleft-related SSD to ensure appropriate management. Representation of these feature categories in classification systems could support understanding of speech in this population. Speech processing skills could be involved in the development and/or persistence of different active CSCs in individual children. Reflection and discussion on how cleft-related SSD is represented in classification systems in relation to other SSD subtypes may inform future iterations of these systems. Further work is needed to understand factors influencing the development and/or persistence of active CSCs, including speech processing skills.

WHAT THIS PAPER ADDS

What is already known on the subject Cleft-related speech sound disorder (SSD) is commonly described as being of known origin. The features of cleft-related SSD have been described extensively and several authors have also examined factors which may contribute to speech development and outcomes in children born with cleft palate +/- lip. There is limited evidence regarding the role of speech processing in the development and persistence of cleft-related SSD. What this study adds This paper reflects on how cleft-related SSD is represented in SSD classification systems in relation to key feature categories of cleft-related SSD and possible causal pathways for passive features and active cleft speech characteristics (CSCs). The role of cognitive speech processing skills is specifically considered alongside other factors that may contribute to the development of active CSCs. What are the clinical implications of this work? Causal pathways for different features of cleft-related SSD may vary, particularly between passive and active features, abut also between different active CSCs. Speech and language therapists (SLTs) need to differentially diagnose passive speech features and active CSCs. Consideration of the role of different speech processing skills and interactions with other potentially influencing factors in relation to active CSCs may inform clinical hypotheses and speech and language therapy (SLT) intervention. Representing key features of cleft-related SSD in classification systems may support understanding of cleft-related SSD in relation to other SSD subtypes.

Evidence Mapping and Quality Analysis of Systematic Reviews on Various Aspects Related to Cleft Lip and Palate

BACKGROUND

Management of cleft lip and palate is interdisciplinary. An evidence-mapping approach was envisaged to highlight the existing gaps in this field, using only the highest level of evidence.

OBJECTIVES

To conduct evidence mapping and quality analysis of systematic reviews and meta-analyses related to any aspect of cleft lip and palate.

SEARCH METHODS

The cleft lip and palate field was divided into 9 domains and 50 subdomains and a method of categorization of systematic reviews was established. A comprehensive search strategy was carried out in seven databases along with the search of gray literature and references of included articles.

SELECTION CRITERIA

Systematic reviews related to any aspect of cleft lip and palate, conducted by a minimum of two reviewers, with a comprehensive search strategy and adequate quality analysis were included.

DATA COLLECTION AND ANALYSIS

A self-designed, pre-piloted data-extraction sheet was used to collect information that was analyzed through an expert group discussion. Quality analysis was performed using ROBIS-I, AMSTAR 2, and the PRISMA checklist.

RESULTS

A total of 144 systematic reviews published between 2008 and 2022 were included. The largest number of these could be categorized in the therapeutic domain (n = 58). A total of 27% of the studies were categorized as inconclusive, 40% as partially conclusive, and 33% as conclusive. As per ROBIS-I, 77% of reviews had high risk of bias while 58% were graded as critically low in quality as per AMSTAR 2. The majority of systematic reviews showed low reporting errors.

CONCLUSIONS

The majority of systematic reviews related to cleft lip and palate relate to therapeutic and prognostic domains and show high risk of bias and critically low quality regardless of the source journal. The results of this paper might serve as a starting point encouraging authors to carry out high-quality research where evidence is lacking.

REGISTRATION

A multidisciplinary expert-group formulated an a priori protocol, registered in Open Science Framework (DOI 10.17605/OSF.IO/NQDV2).

How differences in anatomy and physiology and other aetiology affect the way we label and describe speech in individuals with cleft lip and palate

BACKGROUND

Speech in individuals with cleft lip and/or palate (CLP) is a complex myriad of presenting symptoms. It is uniquely associated with the structural difference of velopharyngeal insufficiency (VPI), together with a wide and heterogeneous range of other aetiologies which often co-occur. The nature of the speech sound disorder (SSD) including VPI may also change over the course of an individual's care pathway. Differences in terminology and approaches to analysis are currently used, resulting in confusion internationally. Additionally, current diagnostic labels and classification systems in SSD do not capture the complexity and full nature of speech characteristics in CLP.

AIMS

This paper aims to explore the different aetiologies of cleft palate/VPI speech and to relate aetiology with speech characteristic(s). In so doing, it attempts to unravel the different terminology used in the field, describing commonalities and differences, and identifying overlaps with the speech summary patterns used in the United Kingdom and elsewhere. The paper also aims to explore the applicability of current diagnostic labels and classification systems in the non-cleft SSD literature and illustrate certain implications for speech intervention in CLP.

METHODS AND PROCEDURES

The different aetiologies were identified from the literature and mapped onto cleft palate/VPI speech characteristics. Different terminology and approaches to analysis are defined and overlaps described. The applicability of current classification systems in SSD is discussed including additional diagnostic labels proposed in the field.

OUTCOMES AND RESULTS

Aetiologies of cleft palate/VPI speech identified include developmental (cognitive-linguistic), middle ear disease and fluctuating hearing loss, altered oral structure, abnormal facial growth, VPI-structural (abnormal palate muscle) and VPI-iatrogenic (maxillary advancement surgery). There are four main terminologies used to describe cleft palate/VPI speech: active/passive and compensatory/obligatory, which overlap with the four categories used in the UK speech summary patterns: anterior oral cleft speech characteristics (CSCs), posterior oral CSCs, non-oral CSCs and passive CSCs, although not directly comparable. Current classification systems in non-cleft SSD do not sufficiently capture the full nature and complexity of cleft palate/VPI speech.

CONCLUSIONS AND IMPLICATIONS

Our attempt at identifying the heterogeneous range of aetiologies provides clinicians with a better understanding of cleft palate/VPI speech to inform the management pathway and the nature and type of speech intervention required. We hope that the unravelling of the different terminology in relation to the UK speech summary patterns, and those used elsewhere, reduces confusion and provides more clarity for clinicians in the field. Diagnostic labels and classification require international agreement.

WHAT THIS PAPER ADDS

What is already known on the subject Speech associated with cleft palate/velopharyngeal insufficiency (VPI) is a complex myriad of speech characteristics with a wide and heterogeneous range of aetiologies. Different terminology and speech summary patterns are used to describe the speech characteristics. The traditional classification of cleft palate/VPI speech is Articulation Disorder, although evidence is building for Phonological Disorder and contrastive approaches in cleft speech intervention. What this paper adds to existing knowledge This paper explores the range of aetiologies of cleft palate/VPI speech (e.g., altered oral structure, abnormal facial growth, abnormal palate muscle and iatrogenic aetiologies) and attempts to relate aetiology with speech characteristic(s). An attempt is made at unravelling the different terminology used in relation to a well-known and validated approach to analysis, used in the United Kingdom and elsewhere. Complexities of current diagnostic labels and classifications in Speech Sound Disorder to describe cleft palate/VPI speech are discussed. What are the potential or actual clinical implications of this work? There needs to be a common language for describing and summarising cleft palate/VPI speech. Speech summary patterns based on narrow phonetic transcription and correct identification of aetiology are essential for the accurate classification of the speech disorder and identification of speech intervention approaches. There is an urgent need for research to identify the most appropriate type of contrastive (phonological) approach in cleft lip and/or palate.

Clinical Linguistics: Analysis of Mapping Knowledge Domains in Past, Present and Future

Across the world, many infants, children, adults, and elderly people are reported with many types of disorders and disabilities that damage, delay, or impede typical language development and/or use. Speech-language pathologists and other relevant clinicians are responsible for diagnosing, assessing, and rehabilitating these conditions. In nearly all types of disorders or disabilities that affect language, clinical linguistics plays a significant role in their study, diagnosis, and evaluation. This study provides a thorough analysis of the field of clinical linguistics. Data from Scopus, WOS, and Lens were used between 1981 and 2022. The documents included in the analysis were 1685, 1628, and 2677 articles published between 1981 and 2022 in clinical linguistics in Scopus, WOS, and Lens, respectively. For the purpose of assessing the development and impacts of the field of clinical linguistics, we used eight bibliometric and eight scientometric indicators. As part of the study, the results summarized the top contributors to clinical linguistics in terms of production size by year, country, university/research centre, journal, publisher, and author. The impact of the examined evidence on clinical linguistics was visualized and tabulated in the form of visual networks, citation counts, burst, cooccurrence, centrality, and sigma factors that are helpful in identifying the main influencers in clinical linguistics. A few examples of clinical linguistics patterns that are being explored extensively by researchers include cleft palate speech with model theories, visual feedback, motor speech disorders with instrumental analysis, acoustic analysis to understand conversational breakdown, nonlinear phonological theory, aphasic conversation in atypical interaction, and diagnostic markers in functional segments. There are also phonological disorders, William Syndrome, and the use of ultrasound, which may be considered potential clusters of clinical linguistics. A key contribution of this paper is highlighting the importance of clinical linguistics as well as its integration with linguistics, speech-language pathology, neurolinguistics, psycholinguistics, neuroscience, cognitive sciences, psychology, and psychometrics.