Background: Reliability information for the Comprehensive Developmental Inventory for Infants and Toddlers diagnostic (CDIITDT) and screening tests (CDIITST) is inadequate.
Aim: To assess the test-retest and inter-rater reliability of the CDIITDT and CDIITST.
Study design: A repeated measures design was selected.
Subjects: Non-disabled term (n=15; mean age 8.4+/-1.6 months) and preterm infants (n=16; mean age 9.3+/-2.9 months), and children with developmental disabilities (n=15; mean age 24.7+/-11.8 months) were recruited. A single rater assessed the children twice in 3 days to examine the test-retest reliability; and a second rater observed and scored performance while the same rater conducted the first assessment for the inter-rater reliability analysis.
Outcome measures: The raw score, developmental age (DA) and developmental quotient (DQ)/Z score for the six subtests, two motor subdomains and the whole test were used as outcome measures for the CDIITDT and CDIITST.
Results: The test-retest reliabilities for the CDIITDT were rated good for the three pediatric groups (ICC 0.76-1.00), with the exception of moderate ratings for the self-help subtest for the term infants and for the social, self-help and fine-motor DQs for the preterm group. The CDIITDT inter-rater reliabilities were good for the three groups (ICC 0.76-1.00), with the exception of only moderate reliability for the cognitive DQs for the preterm infants. The reliabilities for the whole CDIITST for the three groups were high (ICC 0.93-1.00).
Conclusion: The reliabilities for the whole CDIITDT and its various subtests and the whole CDIITST are acceptable for clinical use.