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In this study we are testing identical and fraternal twins between the ages of 4 and 10 because they can help us understand important genetic and environmental influences on early reading development. These are very important years in literacy development, and a better understanding of the various influences will aid in the identification of children at risk for reading difficulty and in the development of appropriate intervention.

The first part of the study occurs when the twins are 4-5 years of age, during the year before they are expected to attend kindergarten. This phase of the study involves five one hour testing session over a period of 2 weeks. During these sessions the twins are tested on standard measures that include:

  • Vocabulary
  • Memory
  • Language
  • Visual Skills

The twins are also weighed and measured, photographed, and rated by the testers as to whether or not they are identical or fraternal. In order to confirm this rating, a DNA sample is taken, using a painless procedure which involves swabbing the inside of the cheeks with a cotton swab. The DNA collection is voluntary, however, if the DNA is collected, researchers at CU will inform families about the results (whether or not the twins are fraternal or identical) as a benefit of participation.

Follow-up testing is conducted near the end of kindergarten, first, second, and fourth grade. During these hour and 1/2 sessions twins take many of the same tests administered previously, as well as new tests that measure reading and spelling abilities. The fourth grade testing procedures include an increased emphasis on reading and listening comprehension.

In addition, parents and teachers are asked to fill out questionnaires about the twins' attention, activity level, and reading activities.

If you would like more information about this research project, please contact us.



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