The dynamic version of the Bayley-III: Test results and the opinion of practitioners

When problems are suspected with the development of a child, developmental assessment is often carried out as part of the diagnostic process (American Academy of Pediatrics, 2001). The test scores obtained indicate the levels of functioning at that moment in time in the domains investigated. This information appears insufficient for practitioners to formulate and evaluate an intervention and to predict future development (Tzuriel, 2000).
In an attempt to provide more useful information to practitioners, tests have been constructed that are dynamic, rather than static, in nature. Dynamic tests aim at measuring the current skills, learning potential and sensitivity to different types of instruction. They have been designed for various groups, including young children. However, no standardized and well-researched instrument for developmental assessment of young children exists that employs a dynamic procedure.
In the current research project a dynamic procedure has been developed for the Bayley Scales of Infant and Toddler Development - Third Edition (Bayley III, Bayley, 2006). The procedure is to administer the standard version of the Cognition scale and then train the negatively scored items. A week later, the Cognition scale is administered again. The difference between the scores on the second and first test administration is expected to give an indication of the developmental potential of the child.
Initial results on the basis of test administrations with 33 children show that children obtain a higher score on the posttest than on the pretest. Children seem to vary in their degree of developmental potential, as indicated by a large standard deviation of the difference in scores between the pretest and the posttest. Children also appear to differ in the kind of support they benefit from.
In the upcoming year, a larger sample of children with as well as without developmental problems will be tested using the dynamic version of the Bayley-III. We will relate the test scores to the development of a child as measured by a retest after six months. A group of children will be tested with the standard Bayley-III twice with a one-week interval to control for the learning effect. Usefulness of dynamic test results for setting up an intervention will be studied using expert interviews.
The project will be finished by the end of 2013. The developed instrument will be published by Pearson Test Publishers in 2014 if the results support its validity.