Two groups were formed in a randomized, controlled trial: an Experimental group (n = 346), which benefited from specific interventions by trained teachers for a period of two years, and a Control group (n = 1354) with business as usual. For Experimental group in Kindergarten, the interventions were conducted in small groups and focused on…

Two large samples were assessed twice in Grade 1: the control group (Cont; N = 2302), which received no specific interventions, and the experimental group (Exp; N = 484), which received interventions associated with code-related skills (decoding and fluency). We estimated that a mean score of around 50 correctly read words per minute corresponded…