The ReadFree tool for the identification of poor readers: a validation study based on a machine learning approach in monolingual and minority-language children

Abstract

In this study, we validated the "ReadFree tool", a computerised battery of 12 visual and auditory tasks developed to identify poor readers also in minority-language children (MLC). We tested the task-specific discriminant power on 142 Italian-monolingual participants (8-13 years old) divided into monolingual poor readers (N = 37) and good readers (N = 105) according to standardised Italian reading tests. The performances at the discriminant tasks of the "ReadFree tool" were entered into a classification and regression tree (CART) model to identify monolingual poor and good readers. The set of classification rules extracted from the CART model were applied to the MLC's performance and the ensuing classification was compared to the one based on standardised Italian reading tests. According to the CART model, auditory go-no/go (regular), RAN and Entrainment_100bpm were the most discriminant tasks. When compared with the clinical classification, the CART model accuracy was 86% for the monolinguals and 76% for the MLC. Executive functions and timing skills turned out to have a relevant role in reading. Results of the CART model on MLC support the idea that ad hoc standardised tasks that go beyond reading are needed.

Keywords: Bilingualism; Classification and regression tree (CART) model; Developmental dyslexia; Executive functions; Timing skills.

Fig. 1

Heatmap and correlational patterns on monolingual good readers. Negative correlations are depicted in blue, while positive ones in red

Fig. 2

Scree-plot

Fig. 3

Root nodes and the classification yielded by the CART model

Fig. 4

Variable importance order based on the CART model

Fig. 5

Relative cross-validation error for each sub-tree