Table 4 Motor-behavioral assessment and acquired developmental milestones: expressive and receptive communication
From: Developmental delay in Rett syndrome: data from the natural history study
Developmental skill | Parameter estimate ± Standard error, from the generalized estimating equation after adjusting for age at enrollment (Skill not gained vs. gained) | ||
|---|---|---|---|
Classic | Atypical better | Atypical poorer | |
Fix and follow | −2.3 ± 2.2 (p = 0.287) | 8.4 ± 3.0 (p = 0.005) | 2.7 ± 6.4 (p = 0.679) |
Quiet to voice | 1.6 ± 1.5 (p = 0.269) | 4.3 ± 3.2 (p = 0.184) | 7.5 ± 3.3 (p = 0.025) |
Inhibit to no | 5.2 ± 1.0 (p < 0.0001) | 1.6 ± 2.9 (p = 0.586) | 5.1 ± 2.5 (p = 0.038) |
Follow command with gesture | 4.1 ± 0.9 (p < 0.0001) | 6.8 ± 2.6 (p = 0.010) | 0.1 ± 3.2 (p = 0.972) |
Follow command with no gesture | 3.5 ± 1.0 (p = 0.0002) | 4.2 ± 2.6 (p = 0.102) | −2.4 ± 3.0 (p = 0.430) |
Social smile | 10.0 ± 2.9 (p = 0.0007) | N.A. | 1.7 ± 1.6 (p = 0.299) |
Coo | 2.6 ± 1.8 (p = 0.152) | 13.2 ± 2.4 (p < 0.0001) | −2.3 ± 2.8 (p = 0.423) |
Babble | 3.0 ± 2.2 (p = 0.165) | −2.3 ± 2.8 (p = 0.410) | 6.4 ± 3.9 (p = 0.097) |
Single words | 6.3 ± 1.1 (p < 0.0001) | 7.0 ± 1.8 (p = 0.0001) | 3.0 ± 2.3 (p = 0.194) |
Phrases | 7.3 ± 1.2 (p < 0.0001) | 2.9 ± 2.5 (p = 0.248) | 11.8 ± 1.7 (p < 0.0001) |
Gestures | 2.8 ± 0.9 (p = 0.003) | 6.5 ± 2.4 (p = 0.007) | 3.1 ± 2.3 (p = 0.191) |
Points for wants | 7.2 ± 1.1 (p < 0.0001) | 8.1 ± 2.3 (p = 0.0004) | 4.4 ± 6.4 (p = 0.490) |