Treatment of Phonological Disorder: A Feasibility Study With Focus on Outcome Measures

Using ultrasound tongue imaging to support the phonetic transcription of childhood speech sound disorders

This study aims to determine whether adding an additional modality (ultrasound tongue imaging) improves the inter-rater reliability of phonetic transcription in childhood speech sound disorders (SSDs) and whether it enables the identification of different or additional errors in children's speech. Twenty-three English speaking children aged 5-13 years with SSDs of unknown origin were recorded producing repetitions of /aCa/ for all places of articulation with simultaneous audio and ultrasound. Two types of transcriptions were undertaken off-line: (1) ultrasound-aided transcription by two ultrasound-trained speech-language pathologists (SLPs) and (2) traditional phonetic transcription from audio recordings, completed by the same two SLPs and additionally by two different SSD specialist SLPs. We classified transcriptions and errors into ten different subcategories and compared: the number of consonants identified as in error by each transcriber; the inter-rater reliability; and the relative frequencies of error types identified by the different types of transcriber. Results showed that error-detection rates were different across the transcription types, with the ultrasound-aided transcribers identifying more errors than were identified using traditional audio-only transcription. Analysis revealed that these additional errors were identified on the dynamic ultrasound image despite being transcribed as correct, suggestive of subtle motor speech differences. Interrater reliability for classifying the type of error was substantial (κ = 0.72) for the ultrasound-aided transcribers and ranged from fair to moderate for the audio-only transcribers (κ = 0.38 to 0.52). Ultrasound-aided transcribers identified more instances of increased variability and abnormal timing errors than the audio-only transcribers.

Optimizing Outcomes for Children With Phonological Impairment: A Systematic Search and Review of Outcome and Experience Measures Reported in Intervention Research

PURPOSE

Reporting of outcome and experience measures is critical to our understanding of the effect of intervention for speech sound disorders (SSD) in children. There is currently no agreed-upon set of measures for reporting intervention outcomes and experiences. In this article, we introduce the Speech Outcome Reporting Taxonomy (SORT), a tool designed to assist with the classification of outcome and experience measures. In a systematic search and review using the SORT, we explore the type and frequency of these measures reported in intervention research addressing phonological impairment in children. Given the integral relationship between intervention fidelity and intervention outcomes, reporting of fidelity is also examined.

METHOD

Five literature databases were searched to identify articles written or translated into English published between 1975 and 2020. Using the SORT, outcome and experience measures were extracted and categorized. The number of intervention studies reporting fidelity was determined.

RESULTS

A total of 220 articles met inclusion criteria. The most frequently reported outcome domain was broad generalization measures (n = 142, 64.5%), followed by specific measures of generalization of an intervention target (n = 133, 60.5%). Eleven (5.0%) articles reported measures of the impact of the phonological impairment on children's activity, participation, quality of life, or others. Twenty articles (9.1%) reported on parent, child, or clinician experience or child engagement. Fidelity data were reported for 13.4% of studies of interventions.

CONCLUSIONS

The measurement of intervention outcomes is challenging yet important. No single type of measure was reported across all articles. Through using tailored measures closely related to intervention targets in combination with a universal set of measures of intelligibility, the impact of phonological impairment on children's lives, and the experience of receiving and providing intervention, researchers and clinicians could work together to progress insights and innovations in science and practice for children with SSD.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.19497803.

Phonological complexity in intervention for Spanish-speaking children with speech sound disorder

The efficiency of intervention for children with speech sound disorder may be influenced by linguistic complexity of the phonological intervention target. Complex targets, particularly, later-acquired, less-known consonants and consonant clusters, have been linked to greater post-intervention generalization to untargeted phonological structures. Yet there is little direct evidence to support target selection based on linguistic complexity for Spanish-speaking children with speech sound disorder. This intervention study utilizes an experimental single-case design to examine the efficacy of intervention in Spanish using different complex targets (i.e. /ɡɾ/, /bɾ/, and /l/). For each of the four Spanish-speaking children with speech sound disorder, sounds at 0% accuracy during baseline were monitored across the baseline period, during and post-intervention, and at one- and two-month follow-up visits. Over the course of intervention, only one participant achieved mastery of the targeted structure in practiced words. However, all participants demonstrated some amount of broad phonological generalization to untargeted consonants or clusters. Variable learning trajectories and broad phonological generalization are discussed as they relate to participant characteristics and linguistic complexity.

Expansion Points Intervention in Young Children with Speech Sound Disorders: A Multiple Baseline Design

The purpose of this investigation was to evaluate the efficacy of expansion points (EXP) intervention with a modified criterion for preschool children with speech sound disorders (SSD). Three preschool-aged children were enrolled in a single-subject multiple baseline intervention study. Intervention took place over 16 sessions. Pre- and post-intervention data are provided. Three outcome measures (generalization to probe words and gains in percent consonants correct, PCC, in words and in conversation) were evaluated to measure the effectiveness of the EXP intervention. All three of the participants demonstrated gains by the end of the intervention phase when measuring PCC in single words. Two of the three participants demonstrated gains in PCC in conversational speech. Progress on individual phonemes was variable across participants. Utilizing the EXP approach, two of the three children showed gains in all three outcome measures. One child showed variable performance in one outcome measure, improvement in one, and a decrease in one. Findings suggest that EXP should be further explored to evaluate intervention efficacy.

How many words make a sample? Determining the minimum number of word tokens needed in connected speech samples for child speech assessment

Connected speech (CS) is an important component of child speech assessment in both clinical practice and research. There is debate in the literature regarding what size sample of CS is required to facilitate reliable measures of speech output. The aim of this study was to identify the minimum number of word tokens required to obtain a reliable measure of CS across a range of measures. Participants were 776 5-year-olds from a longitudinal community population cohort study (Avon Longitudinal Study of Parents and Children, ALSPAC). Children's narratives from a story retell task were audio-recorded and phonetically transcribed. Automatic analysis of the transcribed speech samples was completed using an automated transcription and analysis system. Measures of speech performance extracted included: a range of profiles of percentage consonant correct; frequency of substitutions, omissions, distortions and additions (SODA); percentage of syllable and stress pattern matches; and a measure of whole word complexity (Phonological Mean Length of Utterance, pMLU). Statistical analyses compared these measures at different CS sample sizes in increments using averages and weighted moving averages, and investigated how measures performed between CS samples grouped into word tokens of at least 50, 75 and 100, and restricted to samples of 50-74, 75-99 and 100-125. Key findings showed that sample sizes of 75 word tokens and above showed minimal differences in most measures of speech output, suggesting that the minimum requirement for samples of CS is a word count of 75. The exception to this is in the case of pMLU and measures of substitutions and distortions when a word count of 100 is recommended.

Applying the phonological intervention taxonomy to expansion points intervention

PURPOSE

The Phonological Intervention Taxonomy (Baker, Williams, McLeod, & McCauley, 2018) was developed on the basis of cataloguing the elements of 15 phonological interventions in the domains of the goal of intervention, the teaching moment, the context (who provides the intervention and where it is provided), and procedural issues. Additionally, three summary measures are computed from the tallying of elements in the taxonomy: concentration (the number of required plus optional elements, with a maximum of 72; flexibility (the number of optional elements compared to the total present for the intervention), and distinctiveness (the number of rare elements plus the number of common elements that are absent). In the present paper, the taxonomy is applied to a novel intervention called Expansion Points Intervention (EXP; Smit, Brumbaugh, Weltsch, & Hilgers, 2018) in order to (a) determine how well the taxonomy captures elements of EXP, and (b) compare EXP to other phonological interventions.

METHOD

The four domains of the taxonomy were systematically applied to EXP to determine which elements were required, optional, or not relevant to the implementation of EXP, using the definitions supplied with the taxonomy.

RESULTS

Of the 72 elements in the taxonomy, 25 were considered required elements in EXP and 15 were considered to be optional, resulting in a concentration of 40 and a flexibility of 37.5 %, both of which were in the lower part of the range for the 15 comparison interventions. By way of contrast, distinctiveness, at 15 % was at the high end of the range.

CONCLUSIONS

Based on the ease with which EXP aligns with elements of the taxonomy, the taxonomy was readily applied to EXP. EXP appeared to be comparable to the 15 original interventions, which means that the principles underlying EXP resemble those of other interventions. The implications of these findings for a theory of therapeutic intervention for phonological disorders are discussed.

Perception of Medial Consonants by Preschoolers With and Without Speech Sound Disorders

Purpose This study compared perception of consonants in medial position by preschoolers, with and without speech sound disorder (SSD), with similar vocabulary and language skills. In addition, we investigated the association between speech perception and production skills. Method Participants were 36 monolingual English-speaking children with similar vocabulary and language skills, half with SSD and half with typical speech and language development (TD). Participants completed a speech perception task targeting phonemes /p, k, s, ɹ/ in /aCa/ disyllables and a comprehensive battery of speech and language measures. Results Children with SSD were significantly less accurate in perceiving speech sound distinctions relative to peers with TD. The phoneme /p/ was perceived significantly more accurately than the three other target phonemes. The correlation between overall perceptual accuracy and overall production accuracy was significant. Furthermore, perceptual accuracy of targets /k, s, ɹ/ was significantly correlated with production accuracy of these phonemes. Conclusions Many children with SSD have greater difficulty perceiving the specific speech sounds they misarticulate. Nonetheless, most children with SSD present with broader perceptual difficulties than peers with TD with similar vocabulary and language skills.