TABLE 1.
Characteristics of the participants
| Characteristic | DHH | TH | P |
|---|---|---|---|
| N | 60 | 71 | |
| Age, yr (SD) | 6.32 (2.08) | 6.07 (1.75) | t(129) = −0.74, p = 0.458 |
| Girls, n (%) | 30 (50%) | 41 (58%) | χ2(1, N = 131) = 0.79, p = 0.375 |
| Nonverbal intelligence (SD)* | 9.51 (2.67) | 10.31 (2.61) | t(121) = 1.66, p = 0.099 |
| Parental education level (SD)† | 3.31 (1.03) | 3.58 (0.96) | t(121) = 1.47, p = 0.143 |
| Age at amplification, yr (SD) | 2.51 (1.29) | ||
| Duration of amplification, yr (SD) | 3.81 (1.87) | ||
| Degree of hearing loss, n (%) | |||
| Mild (26–40 dB) | 2 (3%) | ||
| Moderate (41–60 dB) | 2 (3%) | ||
| Severe (60–80 dB) | 1 (2%) | ||
| Profound (> 80 dB) | 55 (92%) | ||
| Type of amplification, n (%) | |||
| Unilateral cochlear implant | 40 (67%) | ||
| Bilateral cochlear implants | 15 (25%) | ||
| Hearing aid only | 5 (8%) | ||
| Etiology, n (%) | |||
| Congenital | 29 (48%) | ||
| Inner ear anomaly | 14 (23%) | ||
| Waardenburg syndrome | 1 (2%) | ||
| Auditory neuropathy | 2 (3%) | ||
| Unknown | 14 (23%) | ||
| Type of education, n (%) | |||
| Regular schools | 57 (95%) | ||
| Special schools | 3 (5%) |
DHH indicates deaf and hard-of-hearing; TH, typically hearing.
For nonverbal intelligence, age-corrected norm scores are presented. The grand population mean is 10 and the SD is 3. Children 3 to 5 years old were tested with Block Design and Matrix subscales of the Wechsler Preschool and Primary Scale of Intelligence Revised Edition (Wechsler 1989). Children 6 to 10 years of age were tested with Block Design and Picture Arrangement subscales of the Wechsler Intelligence Scale for Children Third Edition (Wechsler 1991). These tests were used because the experimenter had access to them and had received training to administer these versions.
Parental education level: 1 = no/primary education; 2 = lower general secondary education; 3 = higher general secondary education; and 4 = college/university.