Objectives: All subjects suspected of Central Auditory Processing Disorder (CAPD) were previously tested by free recall dichotic digits test (DDT). The study objective was normalization and reliability evaluation of two-pair DDT in 750 native Persian subjects aged 8 to 12 years.
Materials: A total of 750 subjects were divided into five age groups varying between 8 years and 12 years and 11 months old. Each age group had 150 subjects. DDT was tested in free recall condition. For evaluating DDT test-retest reliability, 300 participants (60 subjects in each age group) were tested again after one month.
Results: Right and left ear mean score increased from 71.68(±2.19) and 58.51(±1.71) in the 8-year-old group to 90.26(±1.96) and 88.38(±1.36) in 12-year-old group, respectively. The mean Right Ear Advantage (REA) decreased from 13.16(±2.58) in the 8-year-old group to 1.88(±2.49) in the 12-year-old group. A high stability was observed between test-retest results (P<0.0001).
Discussion: Persian version of two-pair dichotic digits exhibited proper reliability for evaluating 8 to 12-year-old subjects, and the study results can be used for evaluating the dichotic hearing function in subjects of the same age group.