This study assessed the validity and usefulness of the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) Low Motor/Vision accommodated version. Accommodations are adaptations to minimize impairment bias, without altering what the test measures. Of the items, 66% have Low Motor accommodations like enlarged materials; 62% have Low Vision accommodations.
Using a within-subject design, we tested 19 children with the accommodated and standard Bayley-III, in a randomly counterbalanced order. The children had motor and/or visual impairment and a chronological age between 22 and 90 months. The test administrators completed an evaluation form.
A subgroup of children benefited from the accommodations; 2 children obtained a large raw score difference. Test administrators considered the accommodations as practical, and advantageous for most children.
The Low Motor/Vision accommodated version seems to validly assess the development of this population. Future, larger-scale research should study whether the accommodations improve the construct validity of the Bayley-III.
The authors suggest that their low motor/vision accommodated version of the Bayley validly assesses the development of children with these impairments. They suggest future study to determine if the accommodations improve the construct validity of the Bayley.
Departments of Special Needs Education and Youth Care (Ms Visser and Drs Ruiter, van der Meulen, and Ruijssenaars) and Psychometrics and Statistics (Dr Timmerman), Faculty of Behavioural and Social Sciences, University of Groningen, Groningen, The Netherlands.
Correspondence: Linda Visser, MSc, Grote Rozenstraat 38, 9712 TJ Groningen, The Netherlands (Linda.firstname.lastname@example.org).
Grant support: The work reported in this article was supported by grant 157013002 from The Netherlands Organization for Health Research and Development to the authors of this article.
The authors declare no conflicts of interest.