Sara A. Hart|Stephen A. Petrill|Lee A. Thompson
A factorial analysis of timed and untimed measures of mathematics and reading abilities in school aged twins
The Ohio State University|The Ohio State University|Case Western Reserve University
present study examined phenotypic genetic relationship fluency nonfluencybased measures reading mathematics performance participants drawn western reserve reading math project ongoing longitudinal twin project samesex mz dz twins ohio present analyses based testeradministered measures available 228 twin pairs age m986 years measurement models suggested four factors represent data namely decoding fluency comprehension math subsequent quantitative genetic analyses latent factors suggested single genetic factor accounted covariance among four latent factors however also unique genetic effects fluency math independent common genetic factor thus although significant genetic overlap among different reading math skills may independent genetic sources variation related measures decoding fluency mathematics