  Dyslexia is a specific learning disorder related to school failure. Detection
is both crucial and challenging, especially in languages with transparent
orthographies, such as Spanish. To make detecting dyslexia easier, we designed
an online gamified test and a predictive machine learning model. In a study
with more than 3,600 participants, our model correctly detected over 80% of the
participants with dyslexia. To check the robustness of the method we tested our
method using a new data set with over 1,300 participants with age customized
tests in a different environment -- a tablet instead of a desktop computer --
reaching a recall of over 72% for the class with dyslexia for children 9 years
old or older. Our work shows that dyslexia can be screened using a machine
learning approach. An online screening tool based on our methods has already
been used by more than 200,000 people.
