Persian randomized dichotic digits test: Development and dichotic listening performance in young adults

Abstract

Background and Aims: The dichotic listening subtest is an important component of the test battery for auditory processing assessment in both children and adults. A randomized dichotic digits test (RDDT) was created to compensate for sensitivity weakness of double digits when detecting abnormal ear asymmetry during dichotic listening. The aim of this study was the development and  intial evaluation of the Persian randomized dichotic digits test.Method: Persian digits 1-10 (except for the bisyllabic digit, 4) uttered by a native Persian language speaker were recorded in a studio. After alignment of intensity and temporal characteristics of digit waveforms, lists 1 and 2 of the RDDT were reproduced. List 1 of the test was administered at 55 dBHL on 50 right-handed normal hearing individuals (with an equal sex ratio) in the age group of 18-25 years and hearing thresholds of 15 dBHL or better in audiometric frequencies.Results: Mean (standard deviation) of percent-correct score for right and left ears and right ear advantage of the subjects was 94.3 (5.3), 84.8 (7.7), and 9.5 (7.0) percent, respectively. Sixty percent of the subjects showed normal results and unilateral and bilateral deficits were seen in 24 percent and 16 percent, respectively, of studied individuals.Conclusion: It seems the Persian version of RDDT test is the same as the original test as it is able to test ear asymmerty, unilateral and bilateral deficits in dichotic listening