Listening and Processing Skills in Young School Children with a History of Developmental Phonological Disorder.

There is a lack of longitudinal studies on the broad-based outcomes in children with Developmental Phonological Disorder (DPD). The aim of this study was to investigate listening and processing skills in a clinical sample of 7-to-10-year-old children diagnosed with DPD in their preschool years and compare these to same-aged typically developing (TD) children. The Evaluation of Children's Listening and Processing Skills (ECLiPS) was completed by parents of 115 children with DPD and by parents of 46 TD children. The total ECLiPS mean score, and the five subscale mean scores, the proportion of children with clinically significant difficulties (≤10th percentile), and the proportion of children with co-occurrence of clinically significant difficulties on more than one subscale, were calculated. Results showed that the ECLiPS mean scores did not differ between the groups. There was no difference between groups regarding language and literacy, but a higher proportion of children with DPD than TD had difficulties in the total score, speech, and auditory processing, environmental and auditory sensitivity, and pragmatic and social skills. In addition, 33.9% of children with DPD had clinically significant difficulties in two or more subscales compared to 10.9% of TD children.

Whole exome sequencing and polygenic assessment of a Swedish cohort with severe developmental language disorder.

Developmental language disorder (DLD) overlaps clinically, genetically, and pathologically with other neurodevelopmental disorders (NDD), corroborating the concept of the NDD continuum. There is a lack of studies to understand the whole genetic spectrum in individuals with DLD. Previously, we recruited 61 probands with severe DLD from 59 families and examined 59 of them and their families using microarray genotyping with a 6.8% diagnostic yield. Herein, we investigated 53 of those probands using whole exome sequencing (WES). Additionally, we used polygenic risk scores (PRS) to understand the within family enrichment of neurodevelopmental difficulties and examine the associations between the results of language-related tests in the probands and language-related PRS. We identified clinically significant variants in four probands, resulting in a 7.5% (4/53) molecular diagnostic yield. Those variants were in PAK2, MED13, PLCB4, and TNRC6B. We also prioritized additional variants for future studies for their role in DLD, including high-impact variants in PARD3 and DIP2C. PRS did not explain the aggregation of neurodevelopmental difficulties in these families. We did not detect significant associations between the language-related tests and language-related PRS. Our results support using WES as the first-tier genetic test for DLD as it can identify monogenic DLD forms. Large-scale sequencing studies for DLD are needed to identify new genes and investigate the polygenic contribution to the condition.

Developmental language disorder - a comprehensive study of more than 46,000 individuals.

Developmental language disorder (DLD) is characterized by enduring low language abilities with a significant functional impact, in the absence of biomedical conditions in which language impairment is part of a complex of impairments. There is a lack of awareness of DLD even among healthcare professionals. Here we estimated the prevalence of DLD and its links to reading and learning difficulties and physical and mental health in the Danish Blood Donor Study (N = 46,547), where DLD-related information is based on questionnaires (self-report). We compared the questionnaire-derived DLD status with the relevant language-related diagnoses from hospital registers. We also investigated the genetic architecture of DLD in a subset of the cohort (N = 18,380). DLD was significantly associated with reading and learning difficulties and poorer mental and physical health. DLD prevalence was 3.36%-3.70% based on questionnaires, compared with 0.04% in hospital registers. Our genetic analyses identified one genome-wide significant locus, but not a significant heritability estimate. Our study shows that DLD has health-related implications that may last into adulthood, and that DLD may be undiagnosed in general healthcare. Furthermore, DLD is likely more genetically heterogeneous than narrower developmental language phenotypes. Our results emphasize the need to raise awareness of DLD and consider criteria for molecular studies of DLD to reduce case heterogeneity.

Assessment fidelity of a language screening instrument for 4-year-olds.

AIM: The aim of the study was to explore the assessment fidelity of Språkfyran, a language screening instrument for four-year-old children. Språkfyran is a mandatory part of the healthcare program within the Swedish Child Health Service (CHS) and is offered to all four-year-olds in the region Scania in Sweden. METHODS: The study was based on structured observations of twenty-four specialist CHS nurses' adherence to the Språkfyran protocol during screening. RESULTS: All the observed nurses deviated from the test protocol. There was a large variation in the number of deviations from the test protocol per nurse, with the highest number of deviations occurring for three specific testing items. Significantly more deviations were made with four-year-old bilingual children as opposed to four-year-old monolingual children. Half of the nurses did not use the test protocol. CONCLUSIONS: There is a clear need to improve the assessment fidelity of Språkfyran. Both the training that the nurses are offered, and the development of the test, are essential in securing the aim of high-quality work within the CHS. Support from experts in child speech-language development and disorders is suggested to be available at the CHS in Sweden.

Description and prediction of reading decoding skills in Swedish children with Developmental Language Disorder.

AIM: Research is lacking in terms of reading decoding skills among clinical samples of Swedish-speaking children with Developmental Language Disorder (DLD). METHOD: The present cross-sectional study included a sample of 61 children (8-12 years) with DLD attending school language units, years 1 to 5. Our purpose was to study reading decoding skills and predictors for decoding, such as a phonological processing skill (nonword repetition), working memory, and a family history of literacy problems. RESULTS: The results on a combined measure of the word and nonword decoding indicated that only 18% of the children had age-adequate decoding skills. The proportion of age-adequate decoders did not change noticeably with the school year. The participants' decoding skills showed larger deviations to test norm means with higher school years. Hierarchical regression analysis showed that the best predictors of decoding skills were measures of working memory and nonword repetition, followed by school year. These factors significantly contributed to the variance in decoding among our sample of children with DLD. A family history of literacy problems made no contribution to the variance. Conclusions: The findings emphasize the necessity of assessing and following up on literacy development in children with DLD.

Past-tense inflection of non-verbs: a potential clinical marker of developmental language disorder in Swedish children.

AIM: In this paper, we explore the performance of past-tense inflection of non-verbs (NVI) in children with developmental language disorder (DLD) and in typically developing controls, to investigate its accuracy as a clinical marker for Swedish-speaking children with DLD. Further, we investigate the relationship between NVI, nonword-repetition, and family history. METHODS: The sample consists of 36 children with DLD (mean age 9;5 years) and 60 controls (mean age 9;2 years). RESULTS: The DLD group performed significantly lower than the controls on the NVI task, with a large effect size of the difference (d = 1.52). Analysis of the clinical accuracy of NVI resulted in 80.6% sensitivity and 76.6% specificity. NVI was significantly and moderately associated with nonword-repetition in the controls, but not in the DLD group. A positive family history, 80.6% in the DLD group and 6.9% in the controls, was associated with lower performance on NVI. When controlling for group (DLD and controls), a non-significant association between family history and performance on the NVI task was found. CONCLUSIONS: NVI is a potential clinical marker of DLD in Swedish school-aged children, but the current NVI task does not reach the level of being acceptable. Further development of the NVI task is warranted to improve its accuracy.

Latent Semantic Analysis Discriminates Children with Developmental Language Disorder (DLD) from Children with Typical Language Development.

Computer based analyses offer a possibility for objective methods to assess semantic-linguistic quality of narratives at the text level. The aim of the present study is to investigate whether a semantic language impairment index (SELIMI) based on latent semantic analysis (LSA) can discriminate between children with developmental language disorder (DLD) and children with typical language development. Spoken narratives from 54 children with DLD and 54 age matched controls with typical language development were summarized in a semantic representation generated using LSA. A statistical model was trained to discriminate between children with DLD and children with typical language development, given the semantic vector representing each individual child's narrative. The results show that SELIMI could distinguish between children with DLD and children with typical language development significantly better than chance and thus has a potential to complement traditional analyses focussed on form or on the word level.

Nonword repetition--a clinical marker for specific language impairment in Swedish associated with parents' language-related problems.

First, we explore the performance of nonword repetition (NWR) in children with specific language impairment (SLI) and typically developing children (TD) in order to investigate the accuracy of NWR as a clinical marker for SLI in Swedish-speaking school-age children. Second, we examine the relationship between NWR, family aggregation, and parental level of education in children with SLI. A sample of 61 children with SLI, and 86 children with TD, aged 8-12 years, were administered an NWR test. Family aggregation, measured as the prevalence of language and/or literacy problems (LLP) in parents of the children with SLI, was based on family history interviews. The sensitivity and specificity of nonword repetition was analyzed in a binary logistic regression, cut-off values were established with ROC curves, and positive and negative likelihood ratios reported. Results from the present study show that NWR distinguishes well between Swedish-speaking school-children with and without SLI. We found 90.2% sensitivity and 97.7% specificity at a cut-off level of -2 standard deviations for binary scoring of nonwords. Differences between the SLI and TD groups showed large effect sizes for the two scoring measures binary (d = 2.11) and percent correct consonants (PCC) (d = 1.79). The children with SLI were split into two subgroups: those with no parents affected with LLP (n = 12), and those with one or both parents affected (n = 49). The subgroup consisting of affected parents had a significantly lower score on NWR binary (p = .037), and there was a great difference between the subgroups (d = 0.7). When compared to the TD group, the difference from the subgroup with affected parents was almost one standard deviation larger (d = 2.47) than the difference from the TD to the subgroup consisting of non-affected parents (d = 1.57). Our study calls for further exploration of the complex interaction between family aggregation, language input, and phenotypes of SLI.