Table 1.
Child and Family Characteristics by Language Skill Group
| Demographic Variable | Low Skill | Average-to-High Skill | Test Statistics/Effect Size |
|---|---|---|---|
| Child age, M (SD) | |||
| Wave 1 (15 months) | 15.16 (1.80) | 15.01 (1.66) | t(349.26)a = 0.83, ns/.00 |
| Wave 2 (25 months) | 25.25 (2.02) | 25.11 (1.89) | t(360) = 0.64, ns/.00 |
| Wave 3 (5 years) | 5.27 (0.34) | 5.27 (0.33) | t(325) = −0.04, ns/.00 |
| Wave 4 (11 years) | 11.09 (0.30) | 11.09 (0.32) | t(416) = 0.03, ns/.00 |
| Child gender (% female) | 46.8 | 47.7 | χ2(1, N = 421) = 0.04, ns/.01 |
| Firstborn child (%) | 66.2 | 66.7 | χ2(1, N = 420) = 0.01, ns/.01 |
| Ethnicity (% African American) | 82.1 | 24.5 | χ2(1, N = 421) = 139.35, p < .001/.58 |
| Child has one or multiple risks listed below (%) | 29.9 | 24.5 | χ2(1, N = 421) = 1.50, ns/.06 |
| Has established risksb | 15.7 | 7.8 | χ2(1, N = 288) = 4.39, p < .05/.12 |
| Has biological or medical risksb | 22.4 | 13.0 | χ2(1, N = 288) = 4.41, p < .05/.12 |
| Has environmental risksb | 33.6 | 27.3 | χ2(1, N = 288) = 1.35, ns/.07 |
| Maternal age at birth of child, M (SD) | 21.02 (5.15) | 23.18 (5.94) | t(417.88)a = −4.00, p < .001/.04 |
| Living arrangements (%) | χ2(2, N = 420) = 45.52, p < .001/.33 | ||
| Living with a spouse | 8.4 | 35.2 | |
| Living with other adults | 48.8 | 28.8 | |
| Living alone with child | 42.8 | 36.0 | |
| Highest education obtainedc (%) | χ2(2, N = 415) = 65.67, p < .001/.40 | ||
| Less than 12th grade | 53.2 | 22.0 | |
| 12th grade or earned a GED | 33.8 | 31.8 | |
| More than 12th grade | 13.0 | 46.3 | |
| Primary caregiver’s occupation (%) | χ2(2, N = 417) = 9.68, p < .01/.15 | ||
| Employed | 23.0 | 31.3 | |
| In school or a training program | 31.5 | 18.9 | |
| Neither employed nor in school or training | 45.5 | 49.8 | |
| Family income below poverty line (%) | 89.4 | 82.9 | χ2(1, N = 353) = 3.02, ns/.09 |
| Welfare recipient (%) | 69.2 | 41.6 | χ2(1, N = 404) = 31.05, p < .001/.28 |
| Receiving Early Head Start services (%) | 54.7 | 52.7 | χ2(1, N = 421) = 0.17, ns/.02 |
| Covariate | |||
| Maternal Education in years | 8.59 (1.97) | 10.03 (1.74) | t(399.16)a = −7.90, p < .001/.13 |
| Maternal Language | 84.60 (7.91) | 98.88 (10.76) | t(278.44)a = −12.93, p < .001/.36 |
| HOME total scores | 24.58 (3.68) | 28.24 (2.34) | t(233.51)a = −10.45, p < .001/.27 |
| Child Social Interaction | 4.53 (0.90) | 5.22 (0.78) | t(305) = −7.19, p < .001/.15 |
| Demographic Variable | Low Skill | Average-to-High Skill | Test Statistics/Effect Size |
| Bayley Visual/Spatial factor | 3.62 (2.64) | 6.89 (2.78) | t(294) = −10.22, p < .001/.26 |
| WISC Matrix Reasoning | 6.26 (2.93) | 10.57 (2.94) | t(415.96)a = −15.07, p < .001/.35 |
Note. Reported effect size for a t-test is partial eta squared and for a Chi-Square test is the phi coefficient (for a 2 by 2 table) or equivalent (for a 2 by 3 table). Eta squared values of .01, .06, and .14 are considered small, medium, and large effect sizes, respectively (Cohen, 1988). For a test of only one predictor variable, partial eta squared is equivalent to eta squared. Phi values of .1, .3, and .5 are considered small, medium, and large effect sizes, respectively (Cohen, 1988).
Modified degrees of freedom are reported for the separate-variance t-test.
Variable value was coded as “1” if child had risks or data were ambiguous, “0” if child had no risks, otherwise variable was set to missing. These categories of risks are used by most states to identify young children at risk for adverse developmental outcomes. Examples of established risks are a chromosomal abnormality, a congenital birth defect, a sensory impairment, or HIV/AIDS. Examples of biological or medical risks are congenital heart disease, diabetes, low birth weight, or a severe chronic illness. Examples of environmental risks are parental substance abuse, low maternal education, suspected child abuse or neglect, family social disorganization, or homelessness.
Recoded from years of education. Years of education was used in SEM.