Last week, a new scientific article on dysgraphia was published in the journal PLOS One. It focused on the development or acquisition of handwriting, defining dysgraphia as difficulties in handwriting. (Note that Dysgraphia Life uses a broader definition and helps with many types of difficulties in written expression, not just handwriting.)
In this study, a French research group examined a group of nearly 300 "typical" school children as well as ~50 children previously diagnosed with dysgraphia.
They compared a gold standard French handwriting test (originally in Dutch) known as the Concise Evaluation Scale for Children’s Handwriting (the BHK) with a digital assessment of handwriting features. The digital system looked at the size and spacing of handwriting; the dynamics of the child's writing such as speed, speed changes, and time the pen was in the air; pressure applied while writing and the changes in pressure; and the tilt between the pen and the surface of the tablet.
Interestingly, their first finding was that 6% of the children recruited from the school tested positive for dysgraphia on the BHK, consistent with estimates of 5-10% of the population. These children were reassigned to the dysgraphia group. There was no difference in age (~9 years old) or right/left-handedness between the groups, but there were more males (71%) in the dysgraphia group consistent with other studies.
There were 12 digital handwriting features in four categories that could be used determine dysgraphia from no dysgraphia; however, only 3 of those were associated with the improved quality of handwriting in the children without dysgraphia as they aged and progressed in school. Those three were writing size, speed changes, and amount of time the pen was in the air. None of the tilt or pressure features were associated with handwriting quality in non-dysgraphic children. As the authors state,
"These results suggest that the pressure and tilt aspects of handwriting may be particularly central aspects of dysgraphia."
The researchers also found that they could group the children with dysgraphia in 3 "clusters" based on the 12 handwriting features. The first cluster had better handwriting quality scores and contained older children and all of the girls. The second cluster had less consistency and control in their writing speed and little change in the pressure applied during their writing. The third cluster had problems with tilt including smoothly changing the inclination of their pen.
A lot of additional research questions arise from the study: Is there an opportunity to detect dysgraphia through digital writing tests? Could new interventions developed around improving pressure and tilt to help children with dysgraphia? Could the clusters indicate different subgroups of children who may need different training or interventions?
One interesting suggestion from the authors is that digital tablets could potentially be used not only for handwriting assessment but for remediation. Improvement of pressure and tilt could be integrated into engaging digital games for the boys who fall in the 2nd and 3rd clusters. We look forward to more work in this area.
Reference to full article:
Acquisition of handwriting in children with and without dysgraphia: A computational approach. Gargot T, Asselborn T, Pellerin H, Zammouri I, M Anzalone S, Casteran L, Johal W, Dillenbourg P, Cohen D, Jolly C. PLoS One. 2020 Sep 11;15(9):e0237575.