There is need for greater understanding of tests used in assessing all aspects of auditory processing disorder (APD). This is important so that specific deficits can be identified and later remediated with the smallest possible test battery. The American Speech-Language-Hearing Association (ASHA) recommends five areas/domains for behavioral assessment: (a) temporal, (b) binaural (dichotic) separation/integration, (c) monaural low redundancy, (d) binaural interaction/localization/lateralization, and (e) auditory discrimination. Multiple-factor studies support the first three domains, which are most often used for APD assessment and which can be measured in a test battery normed within the United States (Multiple Auditory Processing Assessment-2 [MAPA-2]). This study was designed to determine if factored results from children would clarify whether a behavioral test (Listening in Spatialized Noise-Sentences Test [LiSN-S]) would factor within one of the first three domains or be separate, possibly within the fourth domain, binaural interaction.
Fifty-one 8- and 9-year-olds with normal development and normal otoscopy and hearing responses bilaterally from 500 to 4000 Hz at 20 dB HL were recruited. Two sets of APD tests were administered: MAPA-2 and LiSN-S.
Results verified the expected three-factor structure for MAPA-2. LiSN-S did not factor within one of those three, suggesting that some processes involved in the LiSN-S tasks require interactions between the two ears different from those involved in dichotic perception and thus better belong in the ASHA binaural interaction/lateralization domain.
Auditory processing abilities are sufficiently independent of each other that test batteries spanning the first three ASHA domains are not sensitive to at least some abilities in the fourth domain. This additional factor evidence is helpful. Future research should examine the utility of measuring additional factors within APD in order to achieve the most efficient and comprehensive test battery.