McArthur Communicative Development Inventory (CDI; aka “Words & Languages)

Measure DescriptionSource of measure Fenson, L., Bates, E., Dale, P. S., Marchman, V. A., Reznick, J. S., & Thal, D. J. (2007). MacArthur-Bates communicative development inventories. Paul H. Brookes Publishing Company.
Mode of administration Parent report, Teacher report
Age range for use8-37 months. Three versions: "words and gestures" (CDI-WG) for 8-18 months, "words and sentences" (CDI-WS) for 16-30 months, and "CDI-III" for 30-37 months
Domains AssessedUnderstanding and use of words; communicative & symbolic gestures (8-18 mos); grammar & sentence complexity (16-30 and 30-37 mos); language comprehension, symantics, & syntax (30-37 mos)
Related Measures
BurdenTraining needed to administerNot applicable
Minutes to complete20-40 minutes to complete, 10-15 minutes to score
# of items Depends on form - 125 items on CDI-III
Adaptation for AIAN useAdaptedNo
Developer allows adaptation?No
Used with AIAN populations?Yes
AIAN: Cronbach's alpha rangeNone reported yet
AIAN: Evidence of validityNone reported yet
Other populations: Cronbach's alpha rangeLaw and Roy (2008) review the reliability of the CDI: vocabulary and grammar sections are related (r = .62-.76), test-retest reliability (over 6 months) is high for vocabulary (r = .75-.81) and acceptable for grammar (r = .59-.61), and test-retest reliability is even higher over 2 week intervals (.99).
Other populations: Evidence of validityThe CDIs were normed on about 1,800 children in three locations in the U.S. CDI demonstrates concurrent and predictive validity: scores at 2 and 3 years old relate to cognitive tests, receptive language tests, and conversation measures at age 3 (Feldman et al., 2005). The CDI seems to have higher validity in regard to children's production (e.g., what children can say) than for comprehension and grammar (Law & Roy, 2008). CDI differentiates between children with low language skills and chilren with normal language skills (Heilman, Weismer, Evans, & Hollar, 2005). CDI may be more valid when completed by multiple reporters (e.g., mother and child care provider) (Law & Roy, 2008).
SourceDeveloperBrookes Publishing
SummaryComments about sensitivity to changeScores on CDI-WG and CDI-WS improve with age, which demonstrates that the measure is useful for documenting language development over time (Feldman et al., 2000).
General remarks