A Reaching Test Reveals Weak Hand Preference in Specific Language Impairment and Developmental Co-ordination Disorder

A reaching test for quantifying hand preference (QHP task) was given to 7- to 11-year-old children with specific language impairment (SLI) or developmental coordination disorder (DCD). The performance of these clinical children was compared to both an age-matched and younger control group. The four groups did not differ in terms of preferred writing hand or preference on a handedness questionnaire. The QHP measure discriminated the clinical and younger control
groups from the age-matched controls, but not from each other. Right-handed children with SLI, DCD, and the younger controls reached predominantly with the
right hand to spatial positions located to the right of their body’ s midline and with the left hand to positions situated to its left. Right-handers in the age-matched
control group showed a significantly greater tendency to use their right hand to reach to all spatial positions. The increased tendency of the children with SLI to
use the non-preferred hand was particularly striking because it was seen both in those with and without recognised motor difficulties. The QHP task appears to be a sensitive, but non-specific, indicator of developmental disorders.