Bayley Scales of Infant and Toddler Development, Third Edition

About the measure

Rating Psychometric

Rating Implementation

Subscales

Cognitive, Language, motor development and adaptive behaviour

Target construct

Oral language: Receptive and expressive language skills. Social emotional: Communication of needs and self-regulation.

Test Authors

Bayley, N.

Publisher

Pearson

Implementation

AgeⓘAge (in years) covered by the survey. Using the measure outside this age range may result in inaccurate information.

1 month to 42 months year(s)

Prior knowledge required

Individually administered by speech or occupational therapists, mental health professionals and health practitioners with appropriate Graduate and professional qualifications in their field of practice.

ScoringⓘStandardised: Can easily be summed or averaged Complex: Requires judgement or assessment on behalf of the scorer

Complex sets of items a, Scoring requires care to establish norms

TimeⓘAn estimate of the time (in minutes) taken for an individual to complete one survey

Norm referenced min(s)

Psychometric

UK normsⓘWhether the measure has been calibrated with a UK sample (as opposed to generating psychometric details from a Foreign (e.g. USA) sample).

YES

Norm / Criterion referenced

Norm referenced

Standardisation sample

1700 (221 in UK and Ireland)

ReliabilityⓘWhere observations (e.g. teacher or peer report rather than self report) are used, this measure of reliability indicates how closely related each score is. A higher value suggests a more reliable measure.

Reliability coefficients ranged from 0.91 to 0.93. Across all ages, average stability coefficients were .80 or higher. )info from web)

Criterion validityⓘAn assessment of how well the measures relates to other, well-validated assessments.

Comparison of children’s scores on the Bayley-III and the BSID-II, WPPSI-III, PLS‑4, PDMS‑2 and ABAS-II Parent/Primary Caregiver Form (ABAS-II‑P), all no valid tests. Correlations were only moderate.

Construct validityⓘFurther to the use of CFA and EFA, this reports any details demonstrating how well the measure is seen to represent the conceptual domain it comes from.

Test reviews report as insufficient. The Bayley-III cannot be considered a valid test for identifying language disorder/developmental delay and should not be used to identify children with language impairment.

Concurrent validityⓘSimilar to Criterion, this is a measure of how well the measure relates to other similar (or dissimilar) domains, as evidence of its validity.

The highest correlation between the Bayley – III and the WPPSI – III was between the Language composite and the VIQ (r = .83). There is very little difference between the Bayley – III Language composite mean and the WPPSI – III VIQ and FSIQ (98.9, 100.3, and 98.0, respectively).