Children with MLD are less accurate than TA peers on symbolic fraction magnitude comparisons from Grades 4 to 8 and than LA peers from Grade 5, with no group differences in growth rates on the total score¶

Claim · All claims
Evidence · 1 study (2 entries) · associational r2 · q3 · i3 large
Currency · newest study 2013 · checked against its sources 2026-10-20 (automated, 2 of 2 entries) · not reviewed by a person

Subclaims¶

q3 i3 Across all 60 SymMCoF fraction items, TA students outperformed LA students, who outperformed MLD students, and all groups improved from Grades 4 to 8; the MLD and LA groups did not differ in Grade 4 (p = .180) and differed from Grade 5 on. → Mazzocco 2013 q3 i? Growth curve models on total SymMCoF scores revealed no significant differences in growth rates between any of the three groups; on one-half and non-half items analysed separately, growth rates did differ between groups. → Mazzocco 2013 (2)

Evidence¶

Mazzocco 2013¶

Mazzocco, M. M. M., Myers, G. F., Lewis, K. E., Hanich, L. B., & Murphy, M. M. (2013). Limited knowledge of fraction representations differentiates middle school students with mathematics learning disability (dyscalculia) vs. low mathematics achievement. Journal of experimental child psychology, 115(2), 371-387. https://doi.org/10.1016/j.jecp.2013.01.005

q3 · i3 · associational · r2

A 5 (Grade) × 3 (MLD Status) repeated-measures ANOVA on percent correct across all 60 SymMCoF fraction items in the longitudinal sample. The main effect of MLD status was significant, F(2, 119) = 46.30, p < .0001, partial η2 = .438; "students in the TA group were more accurate" than both lower-achieving groups. A small Grade × MLD Status interaction qualifies this: the TA group was more accurate than both other groups at every grade, but the MLD and LA groups were comparable in Grade 4 (p = .180) and the MLD group underperformed the LA group only from Grades 5 to 8.

"students in the TA group were more accurate (89.8%) than peers with either LA (77.9%, p < .01) or MLD (62.1%, p < .001), which also differed from each other, p < .04."

Mazzocco 2013 (2)¶

Mazzocco, M. M. M., Myers, G. F., Lewis, K. E., Hanich, L. B., & Murphy, M. M. (2013). Limited knowledge of fraction representations differentiates middle school students with mathematics learning disability (dyscalculia) vs. low mathematics achievement. Journal of experimental child psychology, 115(2), 371-387. https://doi.org/10.1016/j.jecp.2013.01.005

q3 · i? · associational · r2

Growth curve models on raw SymMCoF total scores, with intercepts set at Grade 4 and slopes in monthly increments, tested whether the groups' trajectories differed. "no significant differences in the growth rates between any of the three groups" were found on the total score, so overall group differences reflect performance level, not rate of growth. Item-type models did find growth differences: on one-half items the MLD group grew faster than the TA group (p < .01), whose scores reached ceiling, and on non-half items the TA group grew faster than the MLD group (p < .05).

"However, results of the GCMs revealed no significant differences in the growth rates between any of the three groups, ps > .35 (Table 2)."

Discussion¶

Learner Variables¶

• Learning Disabilities and Developmental Differences — predictor: learners who differ on it differ in outcomes

Related Claims¶

• Fraction pairs with common denominators are compared more accurately than pairs with common numerators, but children with MLD show a crossover, improving on common numerator items while declining on common denominator items — related
• The one-half advantage in fraction comparison emerges by Grade 4 for TA children and Grade 5 for LA children, but only at Grade 7 for children with MLD, who never exceed ~75% accuracy on one-half items — related
• Visual fraction models yield more accurate magnitude comparisons than Arabic numeral fractions for all ability groups, but the visual model advantage persists through Grade 8 only for children with MLD — related
• Typically achieving children outperform children with mathematical learning difficulties on the SYMP one-digit subtest in Grades 1–5 and the two-digit subtest in Grades 2–5, but not in Grade 6 — related