Table 2.
Characteristics of participants with specific language impairment (SLI), co-occurring ADHD and language impairment (ADHD+LI), and typical development (TD) from clinical and community sources.
| Variable and sample | SLI |
ADHD+LI |
TD |
F(2, 54) | Partial η2 | Contrast | |||
|---|---|---|---|---|---|---|---|---|---|
| n | M (SD) | n | M (SD) | n | M (SD) | ||||
| Age (months) | |||||||||
| Clinical | 8 | 94.5 (7.2) | 8 | 92.5 (8.4) | 8 | 92.4 (4.8) | |||
| Community | 11 | 102.3 (8.9) | 11 | 104.2 (8.9) | 11 | 101.5 (9.1) | |||
| Combined | 19 | 99.0 (8.9) | 19 | 99.3 (10.1) | 19 | 97.7 (8.7) | 0.157 | .006 | SLI = ADHD+LI = TD |
| Maternal educationa | |||||||||
| Clinical | 8 | 4.00 (0.8) | 8 | 3.10 (0.6) | 8 | 3.30 (1.3) | |||
| Community | 11 | 3.20 (0.6) | 11 | 3.00 (1.0) | 11 | 3.45 (1.1) | |||
| Combined | 19 | 3.50 (0.8) | 19 | 3.05 (0.8) | 19 | 3.40 (1.1) | 1.185 | .044 | SLI = ADHD+LI = TD |
| Nonverbalb | |||||||||
| Clinical | 8 | 100.6 (6.3) | 8 | 101.6 (6.4) | 8 | 101.5 (6.2) | |||
| Community | 11 | 100.4 (13.4) | 11 | 93.6 (11.2) | 11 | 107.7 (7.9) | |||
| Combined | 19 | 100.5 (10.7) | 19 | 99.9 (10.2) | 19 | 105.1 (7.7) | 3.44* | .113 | SLI = ADHD+LI < TD |
| Verbal | |||||||||
| Clinicalc | 8 | 65.9 (11.8) | 8 | 70.1 (9.0) | 8 | 106.5 (9.0) | |||
| Communityd | 11 | 73.3 (10.7) | 11 | 74.3 (14.4) | 11 | 100.4 (8.6) | |||
| Combined | 19 | 70.2 (11.4) | 19 | 72.5 (12.3) | 19 | 102.9 (9.1) | 52.35*** | .660 | SLI = ADHD+LI < TD |
| DSM-ADHDe | |||||||||
| Clinical | 8 | 56.1 (7.4) | 8 | 70.8 (9.2) | 8 | 52.5 (4.5) | |||
| Community | 11 | 58.2 (7.4) | 11 | 69.0 (5.9) | 11 | 52.2 (4.9) | |||
| Combined | 19 | 57.31 (7.3) | 19 | 69.7 (7.3) | 19 | 52.3 (4.6) | 35.59*** | .569 | SLI = TD < ADHD+LI |
Note. ADHD = attention-deficit/hyperactivity disorder.
Five-point scale: 1 = some high school, 2 = high school degree, 3 = some college, 4 = college degree, and 5 = some graduate school/advanced degree.
Naglieri Nonverbal Ability Test (Naglieri, 2003) standard score (M = 100, SD = 15).
Clinical Evaluation of Language Fundamentals—Fourth Edition Screening Test (Semel, Wiig, & Secord, 2004) linearized standard scores using screening score means and standard deviations (M = 100, SD = 15).
Clinical Evaluation of Language Fundamentals—Fourth Edition (Semel, Wiig, & Secord, 2003) composite language score (M = 100, SD = 15).
Child Behavior Checklist DSM-IV ADHD subscale (Achenbach & Rescorla, 2001) T score (M = 50, SD = 10; higher scores indicate elevated levels of inattention, impulsivity, and hyperactivity difficulties).
p < .05.
p < .001.