Cognitive Decline in Down Syndrome: A Validity/Reliability Study of the Test for Severe Impairment

Abstract

The utility of the Test for Severe Impairment was studied with 60 older persons who had Down syndrome. Construct validity, test-retest reliability, and interrater reliability were established for the full study group and for subgroups based on degree of mental retardation and dementia status. There was no difference in scores by gender. There were some interesting findings for the group with moderate mental retardation and dementia and the group with severe mental retardation without dementia that may signal specific applications and limitations of the test for use with individuals who have Down syndrome. The internal consistency of the instrument was satisfactory. Results suggest that this test is a useful performance-based task for persons with Down syndrome.

Diagnostic instruments for dementia in older people with intellectual disability in clinical practice

“…Only eight of the 24 points on the TSI require a verbal answer, which is beneficial when testing people with poor verbal ability (Cosgrave et al, 1999). The TSI has been validated in the DS population, and reliability and validity assessed by Cosgrave et al, (1998). They established satisfactory convergent validity and better concurrent validity in comparison with the Down Syndrome Mental Status Examination, a neuropsychological test battery (Haxby, 1989).…”

Test battery for the diagnosis of demntia in individuals with intellectual disability

“…Research is ongoing by Working Group members and colleagues to identify how much change on a given test is clinically significant(e.g. Evenhuis 1996; Prasher 1997; Burt et al 1998 ; Cosgrave et al 1998 ; Dalton & Fedor 1998). To meet the diagnostic criteria for dementia, documented declines on at least one memory test and at least one of the tests of other cognitive ability are required.…”

A preliminary study of the validity of memory tests recommended by the Working Group for individuals with moderate to severe intellectual disability

“…The Test for Severe Impairment (TSI) was originally developed by Albert and Cohen (Albert & Cohen 1992) for use with persons from the general population whose Mini Mental Status Examination score is less than 10 out of 30. Construct validity and test–retest reliability of the TSI were established with individuals with moderate to severe ID from DS, in addition, it has been speculated that the TSI does not show floor effects with these individuals using total score (Cosgrave et al . 1998).…”