A Tablet-Based App to Discriminate Children at Potential Risk of Handwriting Alterations in a Preliteracy Stage.

Failing to master handwriting, as in the case of Dysgraphia, has negative consequences on children's lives. In early stage of development, Dysgraphia diagnosis is delayed and not easily achievable. Thus, the aim of this work is to propose a valid tool to anticipate Dysgraphia screening at a preliteracy age. We developed a tablet application to analyze characteristics altered in dysgraphic handwriting, such as rhythmical laws (isochrony and homothety), or a collection of kinematic and dynamic parameters (smoothness, pressure, frequency contents). To be suitable for the pre-literacy stage, possible alterations are investigated in symbol drawings. The app is tested on 104 preschoolers, both with normal (n=76) and delayed graphical abilities (n=28), reporting excellent acceptance. Some isochrony alterations were reported only for children with delayed graphical abilities. Moreover, kinematic and dynamic parameters are effective in discriminating between risk and norisk conditions. Indeed, the logistic classification adopted resulted in a 0.819 area under the precision-recall curve. These findings pave the way toward an early screening of future handwriting alteration, starting from a pre-literacy age.