Stability of cognitive performance in children with mild intellectual disability. (2nd November 2014)

• Record Type: Journal Article
• Authors: Jenni, Oskar G; Fintelmann, Sylvia; Caflisch, Jon; Latal, Beatrice; Rousson, Valentin; Chaouch, Aziz
• Is Part Of: Developmental medicine & child neurology. Volume 57:Number 5(2015:May)
• Page Start: 463
• Page End: 469
• Publication Date: 2014-11-02
• Subjects: Child development -- Periodicals; Pediatric neurology -- Periodicals; 616.8
• DOI: 10.1111/dmcn.12620
• Languages: English
• ISSNs: 0012-1622

Abstract

<abstract abstract-type="main" id="dmcn12620-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="dmcn12620-sec-0001" sec-type="section"> <title>Aim</title> <p>Longitudinal studies that have examined cognitive performance in children with intellectual disability more than twice over the course of their development are scarce. We assessed population and individual stability of cognitive performance in a clinical sample of children with borderline to mild non‐syndromic intellectual disability.</p> </sec> <sec id="dmcn12620-sec-0002" sec-type="section"> <title>Method</title> <p>Thirty‐six children (28 males, eight females; age range 3–19y) with borderline to mild intellectual disability (Full‐scale IQ [FSIQ] 50–85) of unknown origin were examined in a retrospective clinical case series using linear mixed models including at least three assessments with standardized intelligence tests.</p> </sec> <sec id="dmcn12620-sec-0003" sec-type="section"> <title>Results</title> <p>Average cognitive performance remained remarkably stable over time (high population stability, drop of only 0.38 IQ points per year, standard error=0.39, <italic>p</italic>=0.325) whereas individual stability was at best moderate (intraclass correlation of 0.58), indicating that about 60% of the residual variation in FSIQ scores can be attributed to between‐child variability. Neither sex nor socio‐economic status had a statistically significant impact on FSIQ.</p> </sec> <sec id="dmcn12620-sec-0004" sec-type="section"> <title>Interpretation</title> <p>Although intellectual disability during childhood is a relatively stable phenomenon, individual stability of IQ is only moderate, likely to be caused by test‐to‐test reliability (e.g. level of child's cooperation, motivation, and attention). Therefore, clinical decisions and predictions should not rely on single IQ assessments, but should also consider adaptive functioning and previous developmental history.</p> </sec> </abstract>