Standardizing test scores for a target population: The LMS method illustrated using language measures from the SCALES project

Prevalence and functional impact of social (pragmatic) communication disorders

BACKGROUND

The aim of this study was to evaluate the Children's Communication Checklist-2 (CCC-2) for measuring social-pragmatic communication deficits and to ascertain their prevalence and functional impact in a community sample.

METHODS

We used parent and teacher responses to the CCC-2 to approximate inclusion (poor social-pragmatic skills) and exclusion (poor structural language skills or autistic symptomatology) criteria for social (pragmatic) communication disorder (SPCD). We tested the prevalence of social-pragmatic deficits in a population-based sample of children (n = 386) aged 5-6 years old using CCC-2 algorithms. We also investigated the academic and behavioural profiles of children with broadly defined limitations in social-pragmatic competence on the CCC-2.

RESULTS

Regardless of the diagnostic algorithm used, the resulting prevalence rates for social-pragmatic deficits indicated that very few children had isolated social-communication difficulties (0-1.3%). However, a larger proportion of children (range: 6.1-10.5%) had social-pragmatic skills outside the expected range alongside structural language difficulties and/or autism spectrum symptoms, and this profile was associated with a range of adverse academic and behavioural outcomes.

CONCLUSIONS

A considerable proportion of children in the early years of primary school has social-pragmatic deficits that interfere with behaviour and scholastic activity; however, these rarely occur in isolation. Exclusionary criteria that include structural language may lead to underidentification of individuals with social-pragmatic deficits that may benefit from tailored support and intervention.

Annual Research Review: The transdiagnostic revolution in neurodevelopmental disorders

Practitioners frequently use diagnostic criteria to identify children with neurodevelopmental disorders and to guide intervention decisions. These criteria also provide the organising framework for much of the research focussing on these disorders. Study design, recruitment, analysis and theory are largely built on the assumption that diagnostic criteria reflect an underlying reality. However, there is growing concern that this assumption may not be a valid and that an alternative transdiagnostic approach may better serve our understanding of this large heterogeneous population of young people. This review draws on important developments over the past decade that have set the stage for much-needed breakthroughs in understanding neurodevelopmental disorders. We evaluate contemporary approaches to study design and recruitment, review the use of data-driven methods to characterise cognition, behaviour and neurobiology, and consider what alternative transdiagnostic models could mean for children and families. This review concludes that an overreliance on ill-fitting diagnostic criteria is impeding progress towards identifying the barriers that children encounter, understanding underpinning mechanisms and finding the best route to supporting them.

Relationship between early language competence and cognitive emotion regulation in adolescence

Cognitive emotion regulation improves throughout adolescence and promotes good mental health. Here, we test whether language skills at school entry predict success in emotion regulation in an experimental task at age 10-11, using longitudinal data from the Surrey Communication and Language in Education Study. We additionally compared the performance of children with and without language disorder (LD). Across the whole sample (N = 344), language skills at school entry predicted emotion regulation success in Year 6 (β = 0.23), over and above the concurrent association between language and regulation success. There was no evidence that children with LD that could engage in the task were less successful regulators compared to peers with typical language. However, a quarter of children with LD were unable to complete the task. These children had more severe language difficulties, lower non-verbal IQ and more comorbid conditions. This has implications for clinicians addressing mental health needs for children with neurodevelopmental conditions that affect language, as conversations about emotions and emotion regulation are an integral part of therapy. The longitudinal relationship between language skills and the capacity to use temporal distancing for emotion regulation in early adolescence suggests that language may drive improvements in emotion regulation.

Sources of variability in the prospective relation of language to social, emotional, and behavior problem symptoms: Implications for developmental language disorder

Children with developmental language disorder (DLD) are at risk for social, emotional, and behavioral (SEB) maladjustment throughout development, though it is unclear if poor language proficiency per se can account for this risk as associations between language and SEB appear more variable among typical-language children. This study investigated whether the relationship between language and SEB problems is stronger at very low levels of language and considered confounders including socioeconomic status, sex, and nonverbal intelligence. These were examined using a population-based survey design, including children with a wide range of language and cognitive profiles, and assessed using the Strengths and Difficulties Questionnaire and six standardized language measures (n = 363, weighted n = 6,451). Structural equation models adjusted for prior levels of SEB revealed that the relationship of language at age 5-6 years to SEB at 7-9 years was nonlinear. Language more strongly predicted all clusters of SEB at disordered language levels relative to typical language levels, with standardized betas of -.25 versus .03 for behavioral, -.31 versus -.04 for peer, and .27 versus .03 for prosocial problems. Wald tests between these pairs of betas yielded p values from .049 to .014. Sex moderated the nonlinear association between language and emotional symptoms. These findings indicate a clinical need to support language development in order to mitigate against problems of SEB and to carefully monitor the mental health needs of children with DLD, particularly in the context of multiple, and potentially sex-specific, risks. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Improved NLMS-based adaptive denoising method for ECG signals

BACKGROUND

Traditional least mean square algorithm (LMS) tends to converge faster and thus the larger the steady-state error of the algorithm.

OBJECTIVE

In order to solve this issue, an improved adaptive normalized least mean square (NLMS) ECG signal denoising algorithm is proposed through utilizing the NLMS and the least mean square algorithm with added momentum term (MLMS).

METHODS

The algorithm firstly performs LMS adaptive filtering on the original ECG signal. Then, the algorithm uses the relative error of the prior error signal and the posterior error signal before and after filtering to adaptively determine the iteration step factor. Finally, the expected error is set to determine whether the denoising meets the expected requirements. This method is applied to the MIT-BIH ECG database established by the Massachusetts Institute of Technology.

RESULTS

Experimental results have shown that the proposed algorithm can achieve good denoising for the target signal, and the average signal to noise ratio (SNR) of the proposed method is 17.6016, the RMSE is only 0.0334, and the average smoothness index R is only 0.0325.

CONCLUSION

The proposed algorithm effectively removes the original ECG signal noise, and improves the smoothness of the signal the denoising efficiency.

Two-stage sampling in the estimation of growth parameters and percentile norms: sample weights versus auxiliary variable estimation

BACKGROUND

The use of auxiliary variables with maximum likelihood parameter estimation for surveys that miss data by design is not a widespread approach, despite its documented improved efficiency over traditional approaches that deploy sampling weights. Although efficiency gains from the use of Normally distributed auxiliary variables in a model have been recorded in the literature, little is known about the effects of non-Normal auxiliary variables in the parameter estimation.

METHODS

We simulate growth data to mimic SCALES, a two-stage survey of language development with a screening phase (stage one) for which data are observed for the whole sample and an intensive assessments phase (stage two), for which data are observed for a sub-sample, selected using stratified random sampling. In the simulation, we allow a fully observed Poisson distributed stratification criterion to be correlated with the partially observed model responses and develop five generalised structural equation growth models that host the auxiliary information from this criterion. We compare these models with each other and with a weighted growth model in terms of bias, efficiency, and coverage. We finally apply our best performing model to SCALES data and show how to obtain growth parameters and population norms.

RESULTS

Parameter estimation from a model that incorporates a non-Normal auxiliary variable is unbiased and more efficient than its weighted counterpart. The auxiliary variable method is capable of producing efficient population percentile norms and velocities.

CONCLUSIONS

The deployment of a fully observed variable that dominates the selection of the sample and correlates strongly with the incomplete variable of interest appears beneficial for the estimation process.

Reference values for maximum oxygen uptake relative to body mass in Dutch/Flemish subjects aged 6-65 years: the LowLands Fitness Registry

Background

The maximum oxygen uptake (VO₂max) during cardiopulmonary exercise testing (CPET) is considered the best measure of cardiorespiratory fitness.

Aim

To provide up-to-date reference values for the VO₂max per kilogram of body mass (VO₂max/kg) obtained by CPET in the Netherlands and Flanders.

Methods

The Lowlands Fitness Registry contains data from health checks among different professions and was used for this study. Data from 4612 apparently healthy subjects, 3671 males and 941 females, who performed maximum effort during cycle ergometry were analysed. Reference values for the VO₂max/kg and corresponding centile curves were created according to the LMS method.

Results

Age had a negative significant effect (p < .001) and males had higher values of VO₂max/kg with an overall difference of 18.0% compared to females.

Formulas for reference values were developed:

Males: VO₂max/kg = − 0.0049 × age² + 0.0884 × age + 48.263 (R² = 0.9859; SEE = 1.4364)

Females: VO₂max/kg = − 0.0021 × age² − 0.1407 × age + 43.066 (R² = 0.9989; SEE = 0.5775).

Cross-validation showed no relevant statistical mean difference between measured and predicted values for males and a small but significant mean difference for females. We found remarkable higher VO₂max/kg values compared to previously published studies.

Conclusions

This is the first study to provide reference values for the VO₂max/kg based on a Dutch/Flemish cohort. Our reference values can be used for a more accurate interpretation of the VO₂max in the West-European population.

Early language competence, but not general cognitive ability, predicts children's recognition of emotion from facial and vocal cues

The ability to accurately identify and label emotions in the self and others is crucial for successful social interactions and good mental health. In the current study we tested the longitudinal relationship between early language skills and recognition of facial and vocal emotion cues in a representative UK population cohort with diverse language and cognitive skills (N = 369), including a large sample of children that met criteria for Developmental Language Disorder (DLD, N = 97). Language skills, but not non-verbal cognitive ability, at age 5–6 predicted emotion recognition at age 10–12. Children that met the criteria for DLD showed a large deficit in recognition of facial and vocal emotion cues. The results highlight the importance of language in supporting identification of emotions from non-verbal cues. Impairments in emotion identification may be one mechanism by which language disorder in early childhood predisposes children to later adverse social and mental health outcomes.