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Thursday, April 8, 2021

NIH-funded research team develops language test for people with Down syndrome


A research team funded by the National Institutes of Health have developed a test to evaluate the expressive language skills of people with Down syndrome, a condition resulting from an extra copy or piece of chromosome 21. Expressive language is the use of words to convey meaning to others. Language delays are common in people with Down syndrome, and the study authors believe their test provides a more effective way to evaluate prospective language interventions, compared to current evaluation methods.

The study was conducted by Angela Thurman, Ph.D., of the University of California, Davis, and appears in the Journal of Neurodevelopmental Disorders. Funding was provided by NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development and National Center for Advancing Translational Sciences.

The 107 participants in the study ranged from 6 to 23 years old, and all had an IQ of 70 or less. Researchers engaged the participants in conversation, which was recorded, transcribed and scored on the basis of talkativeness, vocabulary, sentence structure and other aspects of spoken language. Participants took the test again four weeks later. Test scores were consistent across both versions, an indication of the test’s reliability. Similarly, scores were consistent with those of other language tests the participants took.

Participants whose language was limited to basic phrases and those who had a developmental level below 4 years of age had difficulty completing the test. The researchers concluded the test was suitable for most individuals with Down syndrome from 6 to 23 years old, but they call for additional studies to develop other measures for those with more limited spoken language skills.


Alice Kau, Ph.D., of the NICHD Intellectual and Developmental Disabilities Branch is available for comment.


Thurman, AJ et al. Spoken language outcome measures for treatment studies in Down syndrome: feasibility, practice effects, test-retest reliability and construct validity of variables generated from expressive language sampling. Journal of Neurodevelopmental Disorders 2021.

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