Linguistic features of Japanese twins at 3 or 4 years of age evaluated by Illinois test of psycholinguistic abilities.

In general, twins have delayed language development early in childhood compared with singletons. The purpose of this study was to clarify the overall linguistic features of twins. A Japanese version of the Illinois Test of Psycholinguistic Abilities (ITPA) was administered in 24 twin pairs (aged 3 to 4 years) at their own homes. The overall language abilities of the twins were in the normal range (based on ITPA normative data: mean scale score 36.0 +/- 6.0 points), and for the ITPA subtests only, Auditory Reception fell within the range of language disorder (mean scale score 24.9 +/- 5.1 points). The findings suggest that in 3- to 4-year-old Japanese twins, overall language abilities are not delayed. However, there may be specific difficulties with auditory reception skills.