Effects of quantitative and qualitative treatment fidelity of an individualized computer-supported early reading intervention delivered by non-professional tutors

• The effects of treatment fidelity in a computer-supported reading intervention were studied.
• Non-professional tutors are able to provide long term individualized intervention.
• Quantity was a strong predictor of effects in Kindergarten and Grade 1.
• Task orientation of the child was the strongest predictor of effects in Grade 1.
• To interpret effects, it is important to include an in depth analysis of treatment fidelity.

This study investigated the effects of treatment fidelity, both quantitative (training time and lesson/program completion) and qualitative (level matching procedures, tutor support, and children's task orientation) on the outcome of an individualized computer-supported reading intervention provided by non-professional tutors (i.e., parents and volunteers). Thirty two children at risk of reading failure (14 Dutch schools) and their tutor participated in Kindergarten and Grade 1. Results indicated that 87% of the tutors were able to provide sufficient to high levels of support, 70% used adequate level matching procedures, and average quantitative treatment fidelity was 67%. Nearly all children showed sufficient to very high task orientation during the lessons. Stepwise regression analyses showed that quantitative treatment fidelity and child task orientation predicted reading outcomes in Kindergarten, after the summer break, and in Grade 1. Quantitative treatment fidelity was the strongest predictor at the first two measurements, and child task orientation in Grade 1.