Table 1.
Demographic characteristics of the typically developing and developmentally delayed samples.
| Variables | TD (n = 140) | DD (n = 110) | χ2 (df) | Cohen's d |
|---|---|---|---|---|
| Categorical variables | ||||
|
| ||||
| Child gender (% male) | 50.7% | 67.3% | 6.93 (1)** | – |
| Child ethnicitya(% Hispanic) | 8.6% | 26.4% | 20.5 (4)*** | – |
|
| ||||
| Continuous variables | M (SD) | M (SD) | t (df) | Cohen's d |
|
| ||||
| Bayley MDIb | 104.4 (11.7) | 60.0 (12.8) | 28.6 (248)*** | 3.62 |
| Family incomec | 4.8 (1.8) | 3.9 (1.9) | 3.6 (247)*** | .46 |
| Maternal education (years of schooling) | 15.7 (2.5) | 14.4 (2.4) | 4.2 (248)*** | .54 |
| Paternal education (years of schooling) | 15.8 (2.9) | 14.0 (2.7) | 4.7 (228)*** | .62 |
Note. χ2 tests and t-tests compare TD versus DD groups.
a
Child ethnicity: African American (DD: 3.6%; TD: 11.4%); Asian American (DD: 3.6%; TD: 0.9%); European (DD: 60.7%; TD: 60.0%); Hispanic American (DD: 26.4%; 8.6%); “Other” (DD: 9.7%; TD: 15.7%).
b
Mental Developmental Index.
c
Family Income measured on 1 to 7 scale; 1 = $0–$15,000, 4 = $35,001–$50,000, 7 = > $95,001.
**
p < .01.
***
p < .001.