Table 1.
Participant characteristics.
| Characteristic | DLD (n = 15) | TLD (n = 47) | p a | Cohen's d b | Variance ratio c |
|---|---|---|---|---|---|
| Gender | 6 girls, 9 boys | 31 girls, 16 boys | .13 | ||
| Age (yrs) | 5.43 (0.92) Range: 4.0 to 6.92 | 5.32 (0.94) Range: 4.0 to 6.83 | .70 | 0.12 | 0.96 |
| Age of first English exposure (months) | 13.07 (16.89) Range: 0 to 48 | 11.85 (15.04) Range: 0 to 48 | .79 | 0.08 | 1.26 |
| Current Span. input/output (% waking hrs) d | 56% (16) Range: 37% to 84% | 53% (16) Range: 24% to 83% | .60 | 0.19 | 1.00 |
| Language of instruction at school/day care | Both: 8 | Both: 20 | .61 | ||
| Eng: 7 | Eng: 20 | ||||
| Span: 0 | Span: 4 | ||||
| N/A: 0 | N/A: 3 | ||||
| Maternal education (1–6) e | 2.27 (1.39) Range: 1 to 6 | 3.40 (1.79) Range: 1 to 6 | .03 | −0.66 | 0.60 |
| Nonverbal Intelligence std. score (Leiter-3) | 100.93 (7.34) Range: 87 to 113 | 105.13 (7.34) Range: 90 to 123 | .06 | −0.57 | 1.00 |
| ITALK English (Parents' 1–5 rating) f | 3.76 (0.76) Range: 2.4 to 4.8 | 4.32 (0.67) Range: 2.6 to 5.0 | .009 | −0.77 | 0.78 |
| ITALK Spanish (Parents' 1–5 rating) f | 3.82 (0.59) Range: 2.6 to 4.6 | 4.29 (0.59) Range: 2.8 to 5.0 | .01 | −0.80 | 1.00 |
| BESA Spanish Morphosyntax std. score | 68.47 (9.49) Range: 55 to 85 | 93.23 (15.35) Range: 55 to 123 | < .001 | −1.74 | 0.38 |
| BESA English Morphosyntax std. score | 73.93 (7.63) Range: 62 to 88 | 100.04 (15.07) Range: 65 to 118 | < .001 | −1.91 | 0.26 |
| BESA Spanish Semantics std. score | 94.4 (11.11) Range: 73 to 113 | 107.36 (12.36) Range: 75 to 130 | < .001 | −1.07 | 0.81 |
| BESA English Semantics std. score | 88.87 (13.65) Range: 65 to 108 | 104.19 (12.36) Range: 75 to 123 | < .001 | −1.21 | 1.22 |
| BESA Language Index g | 85.33 (7.76) Range: 71 to 96 | 107.62 (9.38) Range: 88 to 126 | < .001 | −2.47 | 0.68 |
| Dominance classification h | 9 English, 6 Spanish | 27 English, 20 Spanish | > .99 | ||
| BESA Span–Eng Morphosyntax Difference score | −5.79 (10.96) Range: −30 to 13 | −6.70 (18.98) Range: −55 to 35 | .82 | 0.05 | 0.33 |
Note. DLD = developmental language disorder; TLD = typical language development; yrs = years; hrs = hours; Eng = English; Span = Spanish; std. = standard; Leiter-3 = Leiter International Performance Scale–Third Edition; N/A = not applicable.
p values come from independent-samples t tests for continuous variables and from chi-square tests of independence for categorical variables.
The standardized mean difference between groups in standard deviation units (Cohen's d) was calculated for continuous variables using the following formula for unequal group sizes provided in the work of Kover and Atwood (2013, p. 7): M DLD – M TD / √((n DLD -1)*sd DLD 2 + (n TD -1)*sd TD 2) / (n DLD + n TD -2)). Differences greater than 0.2 are indicated in bold.
Variance ratios (for continuous variables) close to 1.0 (0.8–1.20) are considered well matched (e.g., Kover & Atwood, 2013). Ratios outside this range are indicated in bold.
Current Spanish exposure was determined by completing the Bilingual Input Output Survey from the Bilingual English Spanish Assessment (BESA). The value represents the proportion of the child's waking hours spent interacting in Spanish, averaging the values for hearing and speaking. Times when the child hears or speaks both languages are counted as 50% Spanish in the calculations.
Scale: 1 = < high school, 2 = high school/General Educational Development (GED) diploma, 3 = some college/2-year degree, 4 = bachelor's degree, 5 = master's degree, 6 = doctorate.
The Inventory to Assess Language Knowledge (ITALK) was administered as part of the parent interview. Parents were asked to rate, on a 1–5 scale in each language, their child's breadth of vocabulary, speech sound production, sentence length, grammaticality, and comprehension. These values are the average ratings across all five areas.
The Language Index from the BESA provides a composite measure of overall language ability that combines children's best morphosyntax score (whether Spanish or English) with their best semantics score (whether Spanish or English). For children with mixed dominance, the Language Index could incorporate, for example, their English morphosyntax score and their Spanish semantics score.
Dominance classification was based on seven indicators: Spanish input/output, parent-reported dominance, child preference, expressive vocabulary, expressive morphosyntax, receptive language, and broad language (the higher Language Index score on the BESA, calculated within each language separately). Children were classified as English dominant (n = 36) if the majority of indicators (excluding ties) pointed to English, and as Spanish dominant (n = 26) if the majority of indicators pointed to Spanish.