Handwriting in Children with Developmental Coordination Disorder: Is Legibility the Only Indicator of a Poor Performance?

Dysgraphia Differs Between Children With Developmental Coordination Disorder and/or Reading Disorder

Handwriting deficits, or dysgraphia, are present in several neurodevelopmental disorders. To investigate whether dysgraphia differs according to the associated disorder, we performed a detailed analysis of handwriting in a group of French children with developmental coordination disorders (DCD), reading disorder (RD), or comorbid RD and DCD. Handwriting deficits were investigated at the product (quality of the trace) and the process (movement that generates the trace) levels. Nineteen children with singular RD (among which eight with dysgraphia), 13 children with singular DCD (among which seven with dysgraphia), 16 children with comorbid RD+DCD (among which 11 with dysgraphia), and 20 typically developing children, age 7 to 12, performed the BHK (Brave Handwriting Kinder) test, a standardized assessment of handwriting, on a graphic tablet. Developmental coordination disorders primarily affected handwriting quality, while RD affected slowness and, to a lesser extent, quality. Children with RD, solely or comorbid with DCD, wasted time by lifting and stopping the pen when writing. The comorbidity added to but did not worsen, handwriting difficulties. These results reflect distinct motor impairments and/or strategies in children with DCD or RD. We identified subtypes of dysgraphia and advocated for a fine-grained analysis of the writing process and the assessment of motor and reading skills when studying dysgraphia.

Which outcomes are key to the pre-intervention assessment profile of a child with developmental coordination disorder? A systematic review and meta-analysis

BACKGROUND

Purpose of this study was to determine what key aspects of function should be incorporated to make up a pre-intervention assessment profile of a child with Developmental Coordination Disorder (DCD); more specifically, what aspects of functioning are implicated in DCD and what is their relative impact?

METHODS

A systematic review and meta-analysis were conducted, for which Pubmed, Web of Science, Scopus and Proquest were searched (last update: April 2023, PROSPERO: CRD42023461619). Case-control studies were included to determine point estimates for performances on field-based tests in different domains of functioning. The risk of bias was assessed, and the level of evidence was estimated. Random-effect meta-analyses were performed to calculate the pooled standardized mean differences for domains of functioning and subgrouping was done for clinically relevant subdomains. Heterogeneity was determined with I2.

RESULTS

121 papers were included for analyses. Data of 5923 children with DCD were included (59.8% boys) and 23 619 Typically Developing (TD) children (45.8% boys). The mean (SD) age of the DCD group was 10.3y (1.2) and 9.3y (1.3) for the TD children. Moderate evidence was found for motor performance, executive functions, sensory processing and perceptions, cognitive functions and sports and leisure activities to be affected in children with DCD.

CONCLUSION

Differences between the two groups varied per domain of functioning. This emphasizes the diversity present within children with DCD and provides a rationale for explaining the heterogeneity in this patient group. Yet, results highlight the potential involvement of all these domains and call for clinicians to be alert not only to examine motor skill difficulties but also other aspects of function. Results indicate the need to develop an individualized pre-intervention multi-dimensional assessment profile for each child with DCD. It also supports the important role that clinicians play in an interdisciplinary team to tackle the difficulties encountered by children with DCD.

Developmental coordination disorder subtypes in children: An unsupervised clustering

AIM

To identify subtypes of developmental coordination disorder (DCD) in children.

METHOD

Children with DCD diagnosed through comprehensive evaluation at Robert-Debré Children's University Hospital (Paris, France) were consecutively enrolled from February 2017 to March 2020. We performed an unsupervised hierarchical clustering based on principal component analysis using a large set of variables encompassing cognitive, motor, and visuospatial scores (Wechsler Intelligence Scale for Children, Fifth Edition; Developmental Neuropsychological Assessment, Second Edition; Movement Assessment Battery for Children, Second Edition).

RESULTS

One hundred and sixty-four children with DCD were enrolled (median age 10 years 3 months; male:female ratio 5.56:1). We identified distinct subgroups with mixed visuospatial and gestural disorders, or with pure gestural disorders that predominantly impaired either speed or precision. Associated neurodevelopmental disorders, such as attention-deficit/hyperactivity disorder, did not influence the results of the clustering. Importantly, we identified a subgroup of children with marked visuospatial impairment with the lowest scores in almost all of the evaluated domains, and the poorest school performance.

INTERPRETATION

The classification of DCD into distinct subgroups could be indicative of prognosis and provide critical information to guide patient management, taking into account the child's neuropsychological profile. Beyond this clinical interest, our findings also provide a relevant framework with homogeneous subgroups of patients for research on the pathogenesis of DCD.

WHAT THIS PAPER ADDS

Unsupervised hierarchical clustering identified four subgroups of children with developmental coordination disorder. Two subgroups had combined visuospatial/gestural difficulties, and two had pure gestural disorders. Severe visuospatial impairment was associated with poor performance in most domains including school. Difficulties in the gestural-only clusters were predominantly either gestural precision or speed.

Validation of the Concise Assessment Scale for Children's Handwriting (BHK) in an Italian Population

Handwriting difficulties represent a common complaint among children and may cause a significant delay in motor skills achievement. The Concise Assessment Scale for Children's Handwriting (BHK) assesses handwriting skill in clinical and experimental settings, providing a quick evaluation of handwriting quality and speed through a copying text. The aim of the present study was to validate the Italian adaptation of the BHK in a representative primary school population. Overall, 562 children aged 7-11 from 16 public primary schools of Rome were included and asked to copy a text in 5 min using cursive handwriting. Handwriting quality and copying speed were measured. The included population followed a normal distribution for the BHK quality scores. Sex influenced the total quality scores, whereas school level influenced the copying speed. The BHK quality score was higher in girls (p < 0.05) and resulted as a stable parameter along the school years, without significant variations with regard to the years spent in handwriting exercise (p = 0.76). The handwriting speed was influenced by school level, and significant differences were found for each of the grades from the second to the fifth (p < 0.05), but not for gender (p = 0.47). Both BHK measures represent a helpful tool for the characterization and assessment of children with handwriting difficulties. The present study confirms that sex influences total BHK quality score, while school level influences handwriting speed.