Selma Ruiter

Validity and suitability of the Bayley-III Low Motor/Vision version: A comparative study among young children with and without motor and/or visual impairments

The aim of the present study was to examine the validity of the Bayley-III Low Motor/Vision version, and its suitability for children with motor and/or visual impairment(s). This version contains accommodated items, that is, adaptations to minimize impairment bias, without altering what the test measures. We hypothesized that the accommodations would not affect the item scores of children without impairment, and that children with impairment(s) would benefit from the accommodations. We tested 41 children without impairment and 63 children with impairment with both the standard Bayley-III and the Low Motor/Vision versions, in randomly counterbalanced order. The test administrators filled in an evaluation form. Results showed that the accommodations did not affect the test scores of children without impairment and did improve the test scores of children with impairment on the Cognition scale, while no improvement was found for the other scales. The test administrators indicated that the vast majority of the children with impairment had been able to show their abilities on the test and that the accommodations were beneficial in 29 out of these 52 cases. For some children, the accommodated instrument appeared to be unsuitable because the impairment was too severe. The conclusion is that the accommodations improve the validity of the Bayley-III when used with children with mild to moderate motor and/or visual impairment, especially with regard to the Cognition scale.

The BSID-II-NL: construction, standardisation, and instrumental utility

In this article we present normative and psychometric data for the Dutch version of the Bayley Scales of Infant Development – Second Edition. The BSID-II-NL consists of a translation of the original materials and a Dutch standardisation for the mental, motor and behaviour rating scales. The Dutch translation of the BSID-II was made in such a way as to stay as close to the original version as possible. Only two important adaptations have been made: a broadening of the basal and ceiling levels and a different factor structure for the behaviour rating scale. Studies on the psychometric qualities have proved the BSID-II-NL to be reliable and valid. (Netherlands Journal of Psychology, 64, 16-24.)

A review of the standardized developmental assessment instruments for young children and their applicability to children with special needs

This article provides a review of contemporary instruments for the developmental assessment of children aged 0–4 years and their applicability for children with special needs. The issues involved in the developmental assessment of children with special needs are discussed, and, on the basis of these issues, various instruments are then evaluated. Method: A literature search was carried out for articles about or using standardized developmental assessment instruments for children aged 0–4 years. Results: Eighteen instruments were found, of which 2 were nonverbal and 2 were designed for motor-impaired children. The instruments varied in terms of their suitability for children with special needs. Conclusion: The range of instruments is limited, especially for children younger than 2 years of age. Instruments for children with motor or hearing/language impairments are available, but their psychometric properties need to be researched and improved. For children with a visual impairment, no appropriate instrument is currently available.

Accommodating the Bayley-III for motor and/or visual impairment: A comparative pilot study

Purpose: 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. Methods: 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. Results: 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. Conclusion: 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.

Adaptive assessment of young children with visual impairment

The aim of this study was to assess the effect of adaptations for children with low vision of the Bayley Scales, a standardized developmental instrument widely used to assess development in young children. Low vision adaptations were made to the procedures, item instructions and play material of the Dutch version of the Bayley Scales of Infant Development — Second Edition (BSID-II), and the Original and Low Vision versions were administered to children with visual impairment over an interval of two weeks. Although quantitative analysis revealed no significant differences between the Original and Low Vision versions of the test in children’s scores, feedback from test administrators indicates that the Low Vision materials make the test easier to administer and more engaging for children.

Low Motor Assessment: A Comparative Pilot Study with Young Children With and Without Motor Impairment.

Most of the developmental instruments that measure cognitive development in children rely heavily on fine motor skills, especially for young children whose language skills are not yet well developed. This is problematic when evaluating the cognitive development of young children with motor impairment. The purpose of this study is to assess the need for a Low Motor adapation of a standardized instrument when testing children with motor impairment. To accomplish this, we have adapted the procedures, item instructions and play material of a widely used and standardized instrument, the Bayley Scales of Infant Development-Second Edition (BSID-II, Bayley 1993). The Original and the Low Motor versions were administered to 20 children experiencing typical development and 19 children with motor impairment within a period of two weeks. Results showed that children with motor impairments scored significantly higher on the Low Motor version of the Bayley Mental Scale than on the Original version: a difference of between 5 and 10 points when the score is expressed in terms of a developmental index score. Results from children with typical development support the assumption that item content and difficulty remain unchanged in the Low Motor version.

Low verbal assessment with the Bayley-III

Recently, the authors have developed the Bayley-III-NL Low Verbal for developmental assessment of children with language impairment. The Low Verbal version consists of an accommodated cognition scale, and non-accommodated communication and motor scales. The purpose of the study was to evaluate the validity and added value of the Bayley-III-NL Low Verbal for children with a language impairment, in relation to the standard Bayley-III-NL for children without impairment. We administered the Bayley-III Low Verbal to 69 children with language impairment, and the standard Bayley-III-NL to 1132 children without impairments. We used an evaluation form for test administrators and interviews with developmental psychologists to evaluate the suitability of the Low Verbal version for the target group. We analyzed the test results using nonparametric item response theory (IRT) to investigate whether test results can be reasonably compared across the two groups. The results of the IRT analyses support the validity of the Bayley-III-NL Low Verbal: the test items do not suffer from differential item functioning (DIF) across the two groups, and thus measure the ability levels of interest in the same way. The results of the evaluation form and interviews confirm that the Bayley-III-NL Low Verbal has added value for testing children with a language impairment, especially for children up to 36 months old. It is also suitable for children with general developmental delay. We conclude that the Bayley-III-NL Low Verbal can validly assess the cognitive, language, and motor development of young children with a language impairment and is the preferred instrument for this target group.

Dynamic assessment with the Bayley-III among young children with developmental disabilities

This article describes the results of a pilot study into the newly developed dynamic version of the Bayley-III Cognition scale. We explored the responses of children to the dynamic version (n = 57) and the companion task behavior questionnaire (n = 93) using administrations among children with developmental disabilities. Furthermore, we studied the added clinical value compared to the standard Bayley-III using expert interviews with 6 educational psychologists. Results showed that there is clear variability in the responses of children to the help-steps that belong to the dynamic procedure and in the score difference between the pretest and posttest. The educational psychologists indicated that the dynamic procedure clearly has added value for specific groups of children, such as children in the preliminary stage of school placement and children from socially disadvantaged families. The task behavior questionnaire was evaluated positively by most educational psychologists. We conclude that the dynamic procedure provides added value for the developmental assessment of children with developmental disabilities. We finish with suggestions for future research into the dynamic Bayley-III.