The Bayley-III Scales of Infant and Toddler Development (Bayley-III) assessment enables the assessment of the development of infants and toddlers from birth to 42 months of age.
It covers 5 main scales of development:
* Cognition, language (receptive and expressive)
* Motor development (fine and gross motor subsets)
* Social-emotional scale
* Adaptive behaviour
The Bayley III test was standardised from a demographically stratified sample of 1,700 children ages 16 days to 42 months as well as from samples of children with developmental delay and a range of developmental conditions. It has been found to have a good reliability coefficient, ranging from 0.74 to 0.99 with an average of 0.96 across developmental modules and ages. Similar reliability coefficients were obtained for children presenting with developmental delay and language disorder.
The Cognitive Scale measured very subtle developmental milestones, from a very early stage, including for example, a range of reflexes; how the child responds to various auditory and visual stimuli, whether he shows preference and excitement in anticipation, or looks for an object hidden under a cover. For children of later developmental stages, the assessments essentially focused on imitation of actions with objects, matching shapes and colours, sequence completion, use of symbols, pretend play, concept of big and small, more, heavy, ability to complete a puzzle or to attend to a story being read to them. Additionally, the test measures the ability to memorise in an array of 6, the position of pictures placed upside down, the ability to count to 10, to complete in order a lacing card and finally to repeat up to 5 numbers in the right order from memory. Specific guidelines are given for each item on scoring, for example, score 1 if the child assembled objects within 90 seconds in either trial.
The Social-Emotional and Adaptive Scales are evaluated by parental questionnaire. The reason for this relates to the fact that emotional functioning is best observed from natural settings as opposed to test-taking conditions. Equally, because the adaptive behaviour scale evaluates the attainment of functional skills necessary for the increasing independence of the infant and young child, it is more accurate to measure these skills from the report parents have of the child in a naturalistic living environment. The Social-Emotional scale of the Bayley-III test is derived from the Greenspan Social-Emotional Growth Chart: A Screening Questionnaire for Infants and young Children (Greenspan and Shanker, 2004), and the adaptive behaviour scale included in Bayley-III is based on the Adaptive Behaviour Assessment System –Second Edition (ABAS-II, Harrison and Oakland, 2003), both of which are based on extensive research in areas of human development, paediatrics, and psychiatry. The Adaptive behaviour Scale includes domains of communication (e.g. use sentence with a noun and a verb), community use (e.g. ask to go to park or other favourite community place), functional pre-academics (reads and obeys common signs such as Do Not Enter or Exit), home living (e.g. get own snack from cupboard), health and safety (e.g. put own dirty glass or plate in sink or dishwasher), leisure (play with toys, games with others), self-care (e.g. washes hands with soap), self-direction (e.g. start an activity almost immediately when told to do so), social (e.g. states when others seem happy, sad, scared, or angry) and motor (e.g. picks up flat objects from a surface). In total the questionnaires cover 183 items organised in developmental scales. Responses were scored as 0 for Not Able, 1 for Never, 2 for sometimes when needed, and 3 for always when needed.
|Administer To||Individuals from birth to 428 months old|
|Completion Time||90-120 min|
|Formats||Semi-structured assessment and parental questionnaire|
|Scoring Options||Hand Scoring (immediately after the session and/or on video recording depending on study design)|
Typical applicants will have a background in psychology, psychiatry, paediatrics, nursing, speech therapy or similar, and will be currently employed in that capacity either as a clinician, part of a clinical team or part of a research team. Qualifications and employment information must be provided on the course application form.