Evaluation of noise excitation as a method for detection of hypernasality.

Hypernasality is a disorder where excess nasal resonance is perceived during speech, often as a result of abnormal coupling between the oral and nasal tracts known as velopharyngeal insufficiency (VPI). The most common cause of VPI is a cleft palate, which affects around 1 in 1650 babies, around ⅓ of whom have persistent speech problems after surgery. Current equipment-based assessment methods are invasive and require expert knowledge, and perceptual assessment methods are limited by the availability of expert listeners and differing interpretations of assessment scales. Spectral analysis of hypernasality within the academic community has resulted in potentially useful spectral indicators, but these are highly variable, vowel specific, and not commonly used within clinical practice. Previous works by others have developed noise excitation technologies for the measurement of oral tract transfer functions using resonance measurement devices (RMD). These techniques provide an opportunity to investigate the structural system abnormalities which lead to hypernasality, without the need for invasive measurement equipment. Thus, the work presented in this study adapts these techniques for the detection of hypernasality. These adaptations include augmentation of the hardware and development of the software, so as to be suitable for transfer function measurement at the nostrils rather than the mouth (nRMD). The new method was tested with a single participant trained in hypernasal production, producing 'normal' and hypernasal vowels, and the recordings validated through a listening test by an expert listener and calculation of nasalance values using a nasality microphone. These validation stages indicated the reliability of the captured data, and analysis of the nRMD measurements indicated the presence of a systematic difference in the frequency range 2 to 2.5 kHz between normal and hypernasal speech. Further investigation is warranted to determine the generalisability of these findings across speakers, and to investigate the origins of differences manifesting in the transfer functions between conditions. This will provide new insights into the effects of nasal tract coupling on voice acoustics, which could in turn lead to the development of useful new tools to support clinicians in their work with hypernasality.

Randomized controlled trial comparing Parent Led Therapist Supervised Articulation Therapy (PLAT) with routine intervention for children with speech disorders associated with cleft palate.

BACKGROUND: A total of 68% of pre-school children with cleft palate have speech problems requiring speech therapy. There is a lack of access to regular targeted therapy. Parent training leads to positive outcomes in early communication skills in cleft palate and non-cleft speech disorders. Connected health has been used to address inadequate access to therapy, providing intervention to those who would not otherwise receive therapy. AIMS: To evaluate the speech, activity and participation outcomes of Parent Led, Therapist Supervised, Articulation Therapy (PLAT) compared with routine speech therapy intervention in parent-child dyads. METHODS & PROCEDURES: A total of 44 children, aged 2.9-7.5 years, were included in a two-centre, two-phase randomized controlled trial. Informed consent and assent were obtained. Participants and speech and language therapists (SLTs) were unblinded to the groups. Parents, in the parent-trained group (n = 23), attended 2 days' training, received a detailed speech therapy programme, and undertook intervention over 12 weeks supported by the cleft specialist SLT using FaceTime and one face-to-face session. In the control arm (n = 21), parent-child dyads received six therapy sessions over 12 weeks with a research SLT, comparable with usual care. Speech recordings were undertaken pre- and post-intervention. Percent consonant correct (PCC) was analysed by external SLTs blinded to the time and group. Activity and participation were measured using the Intelligibility in Context Scale (ICS) and Focus on Outcomes for Children Under Six (FOCUS) questionnaire. OUTCOMES & RESULTS: There was no evidence of an interaction between Time and Group or an overall statistical difference between groups for PCC scores. There was a statistically significant difference over time for both groups (words: p < 0.002; confidence interval (CI) = 9.38-16.27; d = 0.57; sentences: p < 0.002; CI = 16.04-25.97; d = 0.23). Effect sizes were medium for words and small for sentences. For intelligibility and participation, there was no evidence of an interaction between Time and Group or an overall statistical difference between groups. A statistically significant difference over time was found for intelligibility (F = 29.97, d.f. = 1, 42, p < 0.001, 95 % CI = 1.45-3.15 d = 0.46) and for participation (F = 14.19, d.f. = 1, 41, p < 0.001 95% CI = 7.63-25.03; d = 0.36) with FOCUS results indicating clinically meaningful (parent-led group) and significant (control group) change in participation. CONCLUSIONS & IMPLICATIONS: PLAT can be as effective as routine care in changing speech, activity and participation outcomes for children with cleft palate, when supported by a specialist cleft SLT using connected health. What this paper adds What is already known on this subject Over 50% of children with cleft palate require speech therapy. However, there is a lack of timely, accessible speech therapy services in the UK and Ireland. Previous studies have shown that parents can deliver therapy effectively, and that connected health can support the delivery of speech therapy. This study aims to provide evidence that parent-led therapy with the supervision of a specialist cleft therapist using FaceTime is effective. What this paper adds to existing knowledge This randomized controlled trial indicates that parents can be trained to deliver therapy for children with cleft palate speech disorders, under the supervision of an SLT. This approach results in improved speech, activity and participation outcomes similar to routine care. What are the potential or actual clinical implications of this work? This study indicates that both parent-led articulation therapy and routine care showed meaningful gains in speech, activity and participation, and that parent-led articulation therapy when supported by a cleft SLT using connected health could be an additional service delivery model for children with cleft palate speech disorders.

Percent Consonant Correct as an Outcome Measure for Cleft Speech in an Intervention Study.

BACKGROUND/AIMS: Percent consonant correct (PCC) was originally described by Shriberg and Kwiatkowski [J Speech Hear Disord. 1982 Aug;47(3):256-70] as a severity metric for phonological speech disorders, and has been adapted and used in many studies on speech sound disorders. It is well-recognized that cleft speech is complex, consisting of several interacting parameters assessed simultaneously, with error sounds not in the listener's own language. In speech outcome studies, narrow phonetic transcription and the reporting of intra- and inter-rater reliability are acknowledged as the gold standard. However, cleft speech brings special challenges to this task, as complex speech disorders are known to be associated with low transcriber agreement. Recent studies informed the decision to use PCC as the primary outcome measure in a cleft speech intervention study, given its common usage and familiarity. The aim was to specifically evaluate the intra- and inter-rater reliability of PCC in an intervention study, in contrast to other types of speech outcome studies. METHODS: Two trained and experienced listeners analyzed 119 recordings, randomly selected from five data points before, during, and following intervention. The PCC score was separately calculated for words and sentences/phrases. RESULTS: Using intraclass correlations (ICCs), Phase 1 results showed poor reliability for targets elicited for words (ICC = 0.07) and sentences/phrases (ICC = 0.42). Differences in classification of errors as glottal stops and consonant deletion accounted for this. Following further training, a second reliability study was undertaken showing improvement in the number of targets elicited in words (ICC = 0.85) and sentences/phrases (ICC = 0.94). There was very good inter-rater reliability for the PCC score on the word dataset (ICC = 0.9) and the sentence dataset (ICC = 0.88). Very good intra-rater reliability (ICC = 1.0) was found for the PCC score in both words and sentences/phrases for each listener. One listener consistently gave higher modified PCC scores. CONCLUSIONS: In cleft speech intervention studies, reliability of the number of targets elicited should be reported. Listeners need to distinguish between glottal articulation and consonant deletion, in order that the PCC score is meaningful. Attention should be paid to where listeners are reliable, but their pattern of scores consistently differs but in a consistent way. More research is needed on measuring the resolution of articulation difficulties in cleft intervention studies.

The Americleft Speech Project: A Training and Reliability Study.

OBJECTIVE: To describe the results of two reliability studies and to assess the effect of training on interrater reliability scores. DESIGN: The first study (1) examined interrater and intrarater reliability scores (weighted and unweighted kappas) and (2) compared interrater reliability scores before and after training on the use of the Cleft Audit Protocol for Speech-Augmented (CAPS-A) with British English-speaking children. The second study examined interrater and intrarater reliability on a modified version of the CAPS-A (CAPS-A Americleft Modification) with American and Canadian English-speaking children. Finally, comparisons were made between the interrater and intrarater reliability scores obtained for Study 1 and Study 2. PARTICIPANTS: The participants were speech-language pathologists from the Americleft Speech Project. RESULTS: In Study 1, interrater reliability scores improved for 6 of the 13 parameters following training on the CAPS-A protocol. Comparison of the reliability results for the two studies indicated lower scores for Study 2 compared with Study 1. However, this appeared to be an artifact of the kappa statistic that occurred due to insufficient variability in the reliability samples for Study 2. When percent agreement scores were also calculated, the ratings appeared similar across Study 1 and Study 2. CONCLUSION: The findings of this study suggested that improvements in interrater reliability could be obtained following a program of systematic training. However, improvements were not uniform across all parameters. Acceptable levels of reliability were achieved for those parameters most important for evaluation of velopharyngeal function.

Universal parameters for reporting speech outcomes in individuals with cleft palate.

OBJECTIVE: To achieve consistency and uniformity in reporting speech outcomes in individuals born with cleft palate with or without cleft lip using perceptual parameters that characterize their speech production behavior regardless of the language or languages spoken. DESIGN: A working group of six individuals experienced in speech and cleft palate was formed to develop a system of universal parameters for reporting speech outcomes in individuals born with cleft palate. The system was adopted in conjunction with a workshop held in Washington, D.C., that was devoted to developing the universal system. The system, which was refined further following the workshop, involves a three-stage plan consisting of (1) evaluation, (2) mapping, and (3) reporting. The current report focuses primarily on the third stage, reporting speech outcomes. RESULTS: A set of five universal speech parameters has been devised for the reporting stage. These consist of (1) hypernasality, (2) hyponasality, (3) audible nasal air emission and/or nasal turbulence, (4) consonant production errors, and (5) voice disorder. Also included are speech understandability and speech acceptability, global parameters that can be reported for any type of speech disorder. The parameters are described in detail, and guidelines for speech-sampling content and scoring procedures in relation to the parameters are presented. CONCLUSION: A plan has been developed to document speech outcomes in individuals with cleft palate, regardless of the spoken language, using a set of five universal reporting parameters and two global speech parameters.

Relationship between perceptual ratings of nasality and nasometry in children/adolescents with cleft palate and/or velopharyngeal dysfunction.

BACKGROUND: Nasometry has supplemented perceptual assessments of nasality, using speech stimuli, which are devoid of nasal consonants. However, such speech stimuli are not representative of conversational speech. A weak relationship has been found in previous studies between perceptual ratings of hypernasality and nasalance scores for passages containing nasal consonants. AIMS: This study aimed to evaluate the relationship between perceptual assessment and acoustic measurements of nasality using controlled speech stimuli. METHODS & PROCEDURE: A perceptual scale (the Temple Street Scale) describing nasality was devised for this study. Fifty children presenting with nasality were assessed using the Temple Street Scale and nasalance scores were obtained for specified speech samples using the Nasometer (Kay Elemetrics 6200.3). The relationship between the perceptual ratings and the nasometry results was evaluated using correlation analysis, test sensitivity, specificity, and overall efficiency. OUTCOMES & RESULTS: Correlation coefficients for perceptual ratings of nasality and nasalance scores ranged from 0.69 to 0.74. The sensitivity of the Nasometer ranged from 0.83 to 0.88; its specificity ranged from 0.78 to 0.95; while its overall efficiency was between 0.82 and 0.92. CONCLUSIONS: The strong relationship between perceptual and acoustic assessments of nasality indicated that the Temple Street Scale and the Nasometer are both valid clinical tools for the evaluation of nasality when a carefully constructed speech sample is used. The need to use the Nasometer as a supplement to perceptual assessment is highlighted.

The cleft audit protocol for speech-augmented: A validated and reliable measure for auditing cleft speech.

OBJECTIVES: To develop an assessment tool for use in intercenter audit studies of cleft speech and to test its acceptability, validity, and reliability. The tool is to be used systematically to record and report speech outcomes, providing an indication of treatment needs and continuing burden of care. SETTING: Regional Cleft Center, U.K. METHODS: The Cleft Audit Protocol for Speech-Augmented (CAPS-A) was developed by three cleft speech experts who identified the key features required from existing assessment measures. Criterion validity was assessed by comparing the Cleft Audit Protocol for Speech-Augmented outcomes reported for 20 cases with clinical assessment results and other investigations. Intra- and interrater reliability were tested following the training of specialist speech and language therapists who used the Cleft Audit Protocol for Speech-Augmented on two occasions to assess 10 cases. The raters evaluated acceptability and ease of using a questionnaire. RESULTS: The mean percentage agreement for criterion validity in each section was 87% (range 70% to 100%). Both intra- and interexaminer reliability were rated as good/very good (Kappa 0.61 to 1.00) for seven sections and moderate (Kappa 0.41 to 0.60) for three sections. Raters reported that the Cleft Audit Protocol for Speech-Augmented was acceptable and easy to use with appropriate training. CONCLUSION: An acceptable, valid, and reliable cleft speech audit tool has been developed based on a small sample. The Cleft Audit Protocol for Speech-Augmented is recommended for use in intercenter audit studies in the U.K. and Ireland and could be used in other English-speaking countries. In addition, it has wider applicability for use in reporting speech outcomes of surgical procedures.

Nasalance scores for normal-speaking Irish children.

OBJECTIVE: To obtain normal nasalance values during the production of a standardized speech sample for Irish children and determine whether significantly different scores exist for different speech stimuli for female and male speakers. DESIGN: Mean nasalance scores were obtained for normal-speaking children during the repetition of 16 test sentences that were categorized according to consonant type within the sentences (high-pressure consonants, low-pressure consonants, nasal consonants). PARTICIPANTS: Seventy children (36 girls and 34 boys, aged 4 years 11 months to 13 years) with normal articulation, resonance, and voice were included. PROCEDURES: Children repeated each of the 16 test sentences individually. The sentences were presented in groups according to consonant type, referred to as sentence categories. Data were collected and analyzed using the Kay nasometer (model 6200.3). Nasalance scores were obtained for the total speech sample and each sentence category. Data were statistically analyzed to investigate the effects of gender, sentence category, and gender by sentence category. RESULTS: Normative nasalance scores were obtained for the total speech sample (26%), high-pressure consonant sentences (14%), low-pressure consonant sentences (16%), and a nasal consonant sentence (51%). There was no significant difference in nasalance scores between male and female speakers. Significant differences were found between each sentence category (p