Person Ability Scores as an Alternative to Norm-Referenced Scores as Outcome Measures in Studies of Neurodevelopmental Disorders.

TitlePerson Ability Scores as an Alternative to Norm-Referenced Scores as Outcome Measures in Studies of Neurodevelopmental Disorders.
Publication TypeJournal Article
Year of Publication2020
AuthorsFarmer CA, Kaat AJ, Thurm A, Anselm I, Akshoomoff N, Bennett A, Berry L, Bruchey A, Barshop BA, Berry-Kravis E, Bianconi S, Cecil KM, Davis RJ, Ficicioglu C, Porter FD, Wainer A, Goin-Kochel RP, Leonczyk C, Guthrie W, Koeberl D, Love-Nichols J, Mamak E, Mercimek-Andrews S, Thomas RP, Spiridigliozzi GA, Sullivan N, Sutton VR, Udhnani MD, Waisbren SE, Miller JS
JournalAm J Intellect Dev Disabil
Volume125
Issue6
Pagination475-480
Date Published2020 11 01
ISSN1944-7558
Abstract

Although norm-referenced scores are essential to the identification of disability, they possess several features which affect their sensitivity to change. Norm-referenced scores often decrease over time among people with neurodevelopmental disorders who exhibit slower-than-average increases in ability. Further, the reliability of norm-referenced scores is lower at the tails of the distribution, resulting in floor effects and increased measurement error for people with neurodevelopmental disorders. In contrast, the person ability scores generated during the process of constructing a standardized test with item response theory are designed to assess change. We illustrate these limitations of norm-referenced scores, and relative advantages of ability scores, using data from studies of autism spectrum disorder and creatine transporter deficiency.

DOI10.1352/1944-7558-125.6.475
Alternate JournalAm J Intellect Dev Disabil
PubMed ID33211814