Question 1: response to intervention
word reading fluency
For our first and main research question, we wanted to evaluate the effect of playing GraphoGame-NL for up to seven weeks at the onset of formal reading instruction, and hypothesised that children playing GraphoGame‑NL would show a larger response to intervention compared to children playing a control game or children who did not play at all. This hypothesis was partly confirmed. In the Belgian sample, children who played the literacy game improved their letter-sound knowledge more than the math and passive control groups (as measured by the accuracy in the timed letter-sound identification task). In addition, we observed faster word reading fluency in this group at T2 with small to medium-sized effects compared to the children assigned to the passive control and, to a lesser extent, the math condition. For the Dutch sample, there was a trend towards faster responses in the timed letter-sound identification task for the reading group compared to the math group. Recombining both samples revealed a nonlinear interaction of exposure to the game and phonological awareness scores at T1 for word reading fluency. Children who scored high on phonological awareness prior to training and played extensively were more fluent readers than could be expected based on phonological awareness and rapid automatised naming alone.