Publications from Previous Projects


Laurie B. Hanich, Nancy C. Jordan, David Kaplan, & Jeanine Dick (2001)
Journal of Educational Psychology, 93(3), 615-626.

Performance Across Different Areas of Mathematical Cognition in Children with Learning Difficulties.

The performance of 210 2nd graders in different areas of mathematical cognition was examined. Children were divided into 4 achievement groups: children with difficulties in mathematics but not in reading (MD-only), children with difficulties in both mathematics and reading (MD/RD), children with difficulties in reading but not in mathematics, and children with normal achievement. Although both MD groups performed worse than normally achieving groups in most areas of mathematical cognition, the MD-only group showed an advantage over the MD/RD group in exact calculation or arithmetic combinations and in problem solving. The 2 groups did not differ in approximate arithmetic and understanding of place value and written computation. Children with MD-only seem to be superior to children with MD/RD in areas that may be mediated by language but not in ones that rely on numerical magnitudes, visuospatial processing, and automaticity.

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Nancy Jordan, David Kaplan, & Laurie Hanich (2002)
Journal of Educational Psychology, 94, 586-597.

Achievement Growth in Children with Learning Difficulties in Mathematics: Findings of a Two-Year Longitudinal Study

The reading and mathematics growth of 180 children was examined over 4 points, spanning 2nd and 3rd grades. Initially, 4 achievement groups were identified: difficulties in mathematics but not in reading (MD only), difficulties in mathematics as well as in reading (MD-RD), difficulties in reading but not in mathematics (RD only), and normal achievement in mathematics and in reading. When IQ, income, ethnicity, and gender were held constant, the MD-only group grew at a faster rate in mathematics than did the MD-RD group. In reading, the RD-only and MD-RD groups grew at about the same rate. Reading abilities influence children's growth in mathematics, but mathematics abilities do not influence children's growth in reading.

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Nancy C. Jordan, Laurie B. Hanich, & David Kaplan (2003)
Child Development, 74(3), 834-850.

 A Longitudinal Study of Mathematical Competencies in Children with Specific Mathematics Difficulties versus Children with Co-Morbid Mathematics and Reading Difficulties

Mathematical competencies of 180 children were examined at 4 points between second and third grades. Children were initially classified into one of 4 groups: math difficulties but normal reading (MD only); math and reading difficulties (MD-RD); reading difficulties but normal math (RD only); and normal achievement in math and reading (NA). The groups did not differ significantly in rate of development. However, at the end of third grade the MD only group performed better than the MD-RD group in problem solving but not in calculation. The NA and RD only groups performed better than the MD-RD group in most areas. Deficiencies in fact mastery and calculation fluency, in particular, are defining features of mathematics difficulties, with or without reading difficulties.

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Nancy C. Jordan, Laurie B. Hanich, and David Kaplan (2003)
Journal of Experimental Child Psychology, 85, 103-119.

Arithmetic Fact Mastery in Young Children: A Longitudinal Investigation

     Children with poor arithmetic fact mastery (PFM; n = 25) at the end of third grade were compared to grade-level peers with good arithmetic fact mastery (GFM; n = 60) in competencies related to reading and mathematics. Children were assessed longitudinally across second and third grades. When predictor variables, such as IQ, were held constant, the PFM and GFM groups performed at about the same level and progressed at a comparable rate on math story problems and on broad reading achievement. The groups also progressed at a comparable rate on broad math achievement, although children with PFM performed at a significantly lower level. Children with PFM showed remarkably little growth on timed number facts during the study period, despite normal growth in other areas of mathematics. Deficits in fact mastery are highly persistent and appear to be independent of reading and language abilities.

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Nancy C. Jordan & Laurie B. Hanich (2003)
Learning Disabilities Research and Practice, 18, (4), 213-221.

Characteristics of Children with Moderate Mathematics Deficiencies: A Longitudinal Perspective

The reading and mathematics achievement and specific mathematical competencies of 74 children were followed over 4 time points during second and third grades. At the beginning of the study, children were classified into one of 4 groups: moderate mathematics deficiencies but normal reading (MMD-only); moderate mathematics and reading deficiencies (MMD/MRD); moderate reading deficiencies but normal mathematics (MRD-only); and normal achievement in reading and mathematics (NA). Although the MMD-only and the MMD/MRD groups started out at the same level in mathematics, the MMD-only group surpassed the MMD/MRD group over time. A parallel pattern in reading was not observed for the MRD-only and MMD/MRD groups, with children in both groups performing at consistently low levels. Weakness in fact retrieval and estimation characterized children with MMD, with or without RD. The MMD-only group showed an advantage over the MMD/MRD group in problem solving. Reading and language strengths help children compensate for deficiencies in selected areas of mathematics.

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