Table 3.

Language Scores From MacArthur Communication and Development Inventories (Short Form) Modified Version at Follow-up (n = 150)

Control (n = 75)Intervention (n = 75)P
Receptive Vocabulary 100 words39.3 (2.7)**51.0 (3.0)**.004**
 Receptive vocabulary (13–17 mo) (n = 62)40.5 (3.7)45.7 (4.4).37
 Receptive vocabulary (18–25 mo) (n = 88)38.3 (3.8)**54.8 (4.1)**.004**
Receptive Vocabulary 50 words in books17.6 (1.3)**23.4 (1.5)**.008**
 Receptive vocabulary (13–17 mo) (n = 62)18.0 (1.7)19.9 (2.2).48
 Receptive vocabulary (18–25 mo) (n = 88)17.4 (1.9)**25.3 (2.1)**.006**
Receptive Vocabulary 50 wds not in books21.6 (1.4)**28.0 (1.6)**.003**
 Receptive vocabulary (13–17 mo) (n = 62)22.6 (2.2)25.8 (2.3).31
 Receptive vocabulary (18–25 mo) (n = 88)21.0 (1.9)**29.5 (2.1)**.004**
Expressive Vocabulary 100 words15.9 (2.3)22.1 (3.1).11
 Expressive vocabulary (13–17 mo) (n = 62)13.5 (2.9)7.9 (1.7).10
 Expressive vocabulary (18–25 mo) (n = 88)17.5 (3.3)*32.1 (4.6)*.01*
Expressive Vocabulary 50 words in books7.2 (1.1)10.3 (1.5).10
 Expressive vocabulary (13–17 mo) (n = 62)6.0 (1.4)3.4 (.9).13
 Expressive vocabulary (18–25 mo) (n = 88)8.0 (1.6)**15.3 (2.3)**.01**
Expressive vocabulary 50 wds not in books8.7 (1.2)11.8 (1.6).13
 Expressive vocabulary (13–17 mo) (n = 62)7.6 (1.5)4.5 (.9).10
 Expressive vocabulary (18–25 mo) (n = 88)9.5 (1.7)**16.9 (2.4)**.01**
  • * P < .05.

  • ** P < .01.

  • F3-165 P < .001. Two-sample t tests with equal variance (mean, SE).