Table 3.
Internal Consistency Reliability, Convergent Validity and Divergent Validity of Measurement Model
| Measure | Latent Variable
|
||||||
|---|---|---|---|---|---|---|---|
| Early receptive vocabulary | RJA | Intentional comm. | Parent linguistic responses | DKCC | Mid-point receptive vocabulary | Later expressive vocabulary | |
| Composite reliability coefficient | .85 | .85 | .84 | .78 | 1.00 | .88 | .94 |
|
| |||||||
| Average variance extracted | .74 | .74 | .72 | .54 | 1.00 | .79 | .85 |
|
| |||||||
| Indicator outer loadings and cross loadings | |||||||
| Time 1 MB-CDI Comprehension | .85 | −.17 | .06 | −.14 | −.03 | .28 | −.15 |
| Time 1 CSBS Comprehension | .87 | .15 | −.06 | .13 | .02 | −.25 | .14 |
| Time 1 CSBS RJA | −.02 | .84 | −.17 | −.25 | −.09 | .02 | .16 |
| Time 2 ESCS RJA | .02 | .88 | .15 | .22 | .08 | −.01 | −.14 |
| Time 1 UCS Intentional communication acts | .16 | −.16 | .88 | .03 | .13 | .01 | −.06 |
| Time 2 ESCS Communication acts | −.20 | .19 | .82 | −.04 | −.16 | −.01 | .07 |
| Time 2 PCFP FI comments | −.09 | −.34 | .34 | .82 | −.19 | .23 | −.06 |
| Time 2 PCFP FI comments with responsive play | .46 | .48 | −.60 | .65 | −.04 | −.64 | .48 |
| Time 2 PCS Linguistic responses | −.27 | .05 | .06 | .73 | .28 | .18 | −.33 |
| Time 2 CSBS Consonant scale | .00 | .00 | −.00 | −.00 | 1.00 | −.00 | .00 |
| Time 3 MB-CDI Comprehension | −.18 | −.30 | .15 | .07 | .19 | .87 | −.21 |
| Time 3 CSBS Comprehension | .15 | .25 | −.12 | −.06 | −.15 | .91 | .17 |
| Time 4 MB-CDI Words said | .08 | −.08 | −.04 | .04 | .09 | .14 | .90 |
| Time 4 UCS Number of different words | −.10 | .03 | .14 | .03 | −.12 | .02 | .91 |
| Time 4 CSBS Words | .03 | .06 | −.10 | −.08 | .03 | −.18 | .95 |
Note. Outer loadings are in bold type. All p values < .001. CSBS = Communication and Symbolic Behavior Scales Developmental Profile Behavior Sample (Wetherby & Prizant, 2002); DKCC = Diversity of key consonants used in communication; ESCS = Early Social Communication Scales (Mundy et al., 2003); FI = Follow-in; Intentional comm. = Intentional communication; MB-CDI = MacArthur-Bates Communicative Development Inventory Words and Gestures Form (Fenson, 2007); PCFP = parent-child free play; PCS = parent-child snack; RJA = responding to joint attention; Time 1 = study entry; Time 2 = 4 months after entry; Time 3 = 12 months after entry; Time 4 = 16 months after entry; UCS = Unstructured communication sample with examiner.