The Colorado Twin Registry (CTR) is a population-based registry housed at the Institute for Behavioral Genetics (IBG), University of Colorado Boulder. Recruitment has been ongoing since 1968. Many samples at IBG were recruited from the CTR, including the Community Twin Sample (CTS), the Infant Twin Sample (ITS), the Longitudinal Twin Sample (LTS), the Colorado Learning Sample (CLS), the CoTwins sample, and the Early Reading Development Sample (ERDS). These samples have contributed to many studies at IBG, including those on early cognition, early reading ability, executive cognitive function, vulnerability to substance abuse and antisocial behavior, pain and analgesia, and cognitive aging.  

The CTR was also used to recruit part of the Adolescent Brain Cognitive Development Study (ABCD), the largest long-term study of brain development and child health in the United States. Criteria for enrollment, recruitment strategies, demographic information and zygosity assignment are explained for each sample in the publications below. Goals, measures, and brief results are provided for each study. The development of the CTR is an ongoing and evolving process, and it has proved to be a valuable resource, relatively representative of the population from which it was drawn.

Publications:

  • Corley, R. P., Reynolds, C. A., Wadsworth, S. J., Rhea, S. A., & Hewitt, J. K. (2019). The Colorado Twin Registry: 2019 Update. Twin Research and Human Genetics, 22(6), 707–715. PUBMED abstract
  • Rhea, S. A., Gross, A. A., Haberstick, B. C., & Corley, R. P. (2013). Colorado Twin Registry: An update. Twin Research and Human Genetics, 16, 351–357. PUBMED abstract.  
  • Rhea, S.A., Gross, A.A., Haberstick, B.C.,& Corley, R. P. (2006). Colorado Twin Registry.Twin Research and Human Genetics, 9(6), 941-9. PUBMED abstract

Supplemental Information:

Colorado Birth Statistics

  • Table 1: Parental Education for Colorado Births, Twin Births, and CTR Births 1984-2004.

  • Table 2: Maternal Ethnicity For Colorado Births, Twin Births and CTR Births 1984 - 2004.

  • Table 3: Percentage of White Non-Hispanic and White Hispanic Colorado Mothers for Colorado Births, Twin Births, and CTR Births 1984 - 2004.

  • Table 4: Ages of Colorado Parents for Colorado Births, Twin Births, and CTR Births 1984 - 2004.

Front Range Colorado Birth Statistics

The Colorado front range includes the following counties: Larimer, Weld, Morgan, Boulder, Broomfield, Adams, Arapahoe, Denver, Jefferson, Gilpin, Summit, Clear Creek, Park, Douglas, Elbert, El Paso, Pueblo & Teller.

  • Table 1B: Parental Education for Front Range Colorado Births, Twin Births, and CTR Births 1984-2004.

  • Table 2B: Maternal Ethnicity For Front Range Colorado Births, Twin Births and CTR Births 1984 - 2004.

  • Table 3B: Percentage of White Non-Hispanic and White Hispanic Front Range Colorado Mothers for Colorado Births, Twin Births, and CTR Births 1984 - 2004.

  • Table 4B: Ages of Front RangeColorado Parents for Colorado Births, Twin Births, and CTR Births 1984 - 2004.