Children with MLD switch between direct subtraction and subtraction by addition based on the magnitude of the subtrahend when solving two-digit subtractions¶

Claim · All claims
Evidence · 1 study · causal r2 · q3
Currency · newest study 2014 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q3 i? For children with MLD, the Switch-Model (reaction times predicted by the minimum of subtrahend and difference) provided the best fit to reaction times on subtraction-format problems, explaining 47 % of the variance. → Peters 2014

Evidence¶

Peters 2014¶

Peters, G., De Smedt, B., Torbeyns, J., Verschaffel, L., & Ghesquière, P. (2014). Subtraction by addition in children with mathematical learning disabilities. Learning and Instruction, 30, 1-8. https://doi.org/10.1016/j.learninstruc.2013.11.001

q3 · i? · causal · r2

Regression analysis of reaction times of 44 children with MLD on 32 subtraction-format problems, comparing DS-, SBA- and Switch-Models. The Switch-Model fit best, "explaining 47 % of the variance"; no standardized effect size was printed.

"Results showed that the model in which children switched between direct subtraction and subtraction by addition based on the magnitude of the subtrahend (Switch-Model) provided the best fit to the data (Table 2), explaining 47 % of the variance."

Discussion¶

Related Claims¶

• At the individual level, the Switch-Model most frequently provided the best fit to MLD children's reaction times, though a substantial subgroup fit the DS-Model or no model — related
• MLD children switch between direct subtraction and subtraction by addition only when the numerical distance between subtrahend and difference is large — related
• Reaction times showed significant main effects of presentation format and numerical distance, but no main effect of magnitude — related
• MLD children's accuracy was low overall and varied by problem type and presentation format — related