TABLE 1

Participant Characteristics at Baseline

VariableTrial Arm
InterventionControl
n4552
Age, months30.3 (5.0)30.6 (5.1)
Receiving additional speech therapy2014
Male8280
Race
 African American1813
 White7885
 Other42
Having receptive and expressive delay6972
Income71 000 (35 000)60 000 (52 000)
Mother’s education
 High school3944
 Undergraduate degree3727
 Graduate degree2429
Baseline scores
 Cognitive skills, BSID-3991.3 (8.4)88.6 (7.6)
 Expressive language, PLS-41275.2 (7.9)75.0 (7.2)
 Receptive language, PLS-41276.5 (17.3)73.8 (15.2)
 Expressive vocabulary, EOWPVT-31360.9 (11.5)59.8 (10.7)
 Expressive vocabulary, NDW19.0 (17.9)17.2 (17.5)
 Expressive vocabulary, MCDI1492.1 (105.1)94.4 (97.2)
  • Data are expressed as mean (SD) or %. BSID-3, Bayley Scales of Infant Development, Third Edition; PLS-4, Preschool Language Scale, Fourth Edition; EOWPVT-3, Expressive One-Word Picture Vocabulary Test, Third Edition; NDW, number of different word roots in a 20-minute play interaction; MCDI, MacArthur Bates Communication Development Inventories.